2.6.27-rc4-git1: Reported regressions from 2.6.26

2.6.27-rc4-git1: Reported regressions from 2.6.26

[Rafael J. Wysocki]

This message contains a list of some regressions from 2.6.26, for which there
are no fixes in the mainline I know of.  If any of them have been fixed already,
please let me know.

If you know of any other unresolved regressions from 2.6.26, please let me know
either and I'll add them to the list.  Also, please let me know if any of the
entries below are invalid.

Each entry from the list will be sent additionally in an automatic reply to
this message with CCs to the people involved in reporting and handling the
issue.


Listed regressions statistics:

  Date          Total  Pending  Unresolved
  ----------------------------------------
  2008-08-23      122       48          40
  2008-08-16      103       47          37
  2008-08-10       80       52          31
  2008-08-02       47       31          20


Unresolved regressions
----------------------

Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11414
Subject		: Random crashes with 2.6.27-rc3 on PPC
Submitter	: Michael Buesch <mb@bu3sch.de>
Date		: 2008-08-23 14:10 (1 days old)
References	: http://marc.info/?l=linux-kernel&m=121950076812616&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11410
Subject		: SLUB list_lock vs obj_hash.lock...
Submitter	: Daniel J Blueman <daniel.blueman@gmail.com>
Date		: 2008-08-22 21:48 (2 days old)
References	: http://marc.info/?l=linux-kernel&m=121944176609042&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11407
Subject		: suspend: unable to handle kernel paging request
Submitter	: Vegard Nossum <vegard.nossum@gmail.com>
Date		: 2008-08-21 17:28 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121933974928881&w=4
Handled-By	: Rafael J. Wysocki <rjw@sisk.pl>
		  Pekka Enberg <penberg@cs.helsinki.fi>
		  Pavel Machek <pavel@suse.cz>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11406
Subject		: patch "x86: MOVE PCI IO ECS code to x86/pci" breaks CPU hotplug
Submitter	: Jan Beulich <jbeulich@novell.com>
Date		: 2008-08-21 12:59 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121932366326572&w=4
Handled-By	: Ingo Molnar <mingo@elte.hu>
		  Robert Richter <robert.richter@amd.com>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11405
Subject		: 2.6.27-rc3 segfault on cold boot; not on warm boot.
Submitter	: David Greaves <david@dgreaves.com>
Date		: 2008-08-21 9:45 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121931198904777&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11404
Subject		: BUG: in 2.6.23-rc3-git7 in do_cciss_intr
Submitter	: rdunlap <randy.dunlap@oracle.com>
Date		: 2008-08-21 5:52 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121929819616273&w=4
		  http://marc.info/?l=linux-kernel&m=121932889105368&w=4
Handled-By	: Miller, Mike (OS Dev) <Mike.Miller@hp.com>
		  James Bottomley <James.Bottomley@hansenpartnership.com>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11403
Subject		: 2.6.27-rc2 USB suspend regression
Submitter	: Jeremy Fitzhardinge <jeremy@goop.org>
Date		: 2008-08-20 20:48 (4 days old)
References	: http://marc.info/?l=linux-kernel&m=121926536103630&w=4
Handled-By	: Alan Stern <stern@rowland.harvard.edu>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11402
Subject		: skbuff bug?
Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
Date		: 2008-08-21 3:56 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121929102707658&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11401
Subject		: pktcdvd: BUG, NULL pointer dereference in pkt_ioctl, bisected
Submitter	: Laurent Riffard <laurent.riffard@free.fr>
Date		: 2008-08-22 08:16 (2 days old)


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11398
Subject		: hda_intel: IRQ timing workaround is activated for card #0. Suggest a bigger bdl_pos_adj.
Submitter	: Frans Pop <elendil@planet.nl>
Date		: 2008-08-21 17:17 (3 days old)


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11388
Subject		: 2.6.27-rc3 warns about MTRR range; only 3 of 16gb of memory is usable
Submitter	: Joshua Hoblitt <j_kernel@hoblitt.com>
Date		: 2008-08-20 17:38 (4 days old)


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11382
Subject		: e1000e: 2.6.27-rc1 corrupts EEPROM/NVM
Submitter	: David Vrabel <david.vrabel@csr.com>
Date		: 2008-08-08 10:47 (16 days old)
References	: http://marc.info/?l=linux-kernel&m=121819267211679&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11380
Subject		: lockdep warning: cpu_add_remove_lock at:cpu_maps_update_begin+0x14/0x16
Submitter	: Ingo Molnar <mingo@elte.hu>
Date		: 2008-08-20 6:44 (4 days old)
References	: http://marc.info/?l=linux-kernel&m=121921480931970&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11379
Subject		: char/tpm: tpm_infineon no longer loaded for HP 2510p laptop
Submitter	: Frans Pop <elendil@planet.nl>
Date		: 2008-08-18 13:40 (6 days old)
References	: http://marc.info/?l=linux-kernel&m=121906698213329&w=4
Handled-By	: Bjorn Helgaas <bjorn.helgaas@hp.com>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11357
Subject		: Can not boot up with zd1211rw USB-Wlan Stick
Submitter	: uwe <kender@freenet.de>
Date		: 2008-08-16 14:17 (8 days old)


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11356
Subject		: Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'
Submitter	: Frans Pop <elendil@planet.nl>
Date		: 2008-08-16 19:11 (8 days old)
References	: http://marc.info/?l=linux-kernel&m=121891396320127&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11355
Subject		: Regression in 2.6.27-rc2 when cross-building the kernel
Submitter	: Larry Finger <Larry.Finger@lwfinger.net>
Date		: 2008-08-16 2:38 (8 days old)
References	: http://marc.info/?l=linux-kernel&m=121885432118368&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11354
Subject		: AMD Elan regression with 2.6.27-rc3
Submitter	: Sean Young <sean@mess.org>
Date		: 2008-08-15 18:37 (9 days old)
References	: http://marc.info/?l=linux-kernel&m=121882578430056&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11343
Subject		: SATA Cold Boot Problems with 2.6.27-rc[23] on nVidia 680i
Submitter	: Manny Maxwell <mannymax@mannymax.net>
Date		: 2008-08-14 4:16 (10 days old)
References	: http://marc.info/?l=linux-kernel&m=121868782917600&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11342
Subject		: Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected
Submitter	: Alan D. Brunelle <Alan.Brunelle@hp.com>
Date		: 2008-08-13 23:03 (11 days old)
References	: http://marc.info/?l=linux-kernel&m=121866876027629&w=4
Handled-By	: Andrew Morton <akpm@linux-foundation.org>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11340
Subject		: LTP overnight run resulted in unusable box
Submitter	: Alexey Dobriyan <adobriyan@gmail.com>
Date		: 2008-08-13 9:24 (11 days old)
References	: http://marc.info/?l=linux-kernel&m=121861951902949&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11336
Subject		: 2.6.27-rc2:stall while mounting root fs
Submitter	: Torsten Kaiser <just.for.lkml@googlemail.com>
Date		: 2008-08-12 12:37 (12 days old)
References	: http://marc.info/?l=linux-kernel&m=121854484015909&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11335
Subject		: 2.6.27-rc2-git5 BUG: unable to handle kernel paging request
Submitter	: Randy Dunlap <randy.dunlap@oracle.com>
Date		: 2008-08-12 4:18 (12 days old)
References	: http://marc.info/?l=linux-kernel&m=121851477201960&w=4
		  http://lkml.org/lkml/2008/8/16/274
Handled-By	: Hugh Dickins <hugh@veritas.com>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11334
Subject		: myri10ge: use ioremap_wc: compilation failure on ARM
Submitter	: Martin Michlmayr <tbm@cyrius.com>
Date		: 2008-08-10 11:25 (14 days old)
References	: http://marc.info/?l=linux-netdev&m=121836771727632&w=2


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11308
Subject		: tbench regression on each kernel release from 2.6.22 -&gt; 2.6.28
Submitter	: Christoph Lameter <cl@linux-foundation.org>
Date		: 2008-08-11 18:36 (13 days old)
References	: http://marc.info/?l=linux-kernel&m=121847986119495&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11282
Subject		: Please fix x86 defconfig regression
Submitter	: Andi Kleen <andi@firstfloor.org>
Date		: 2008-08-07 20:46 (17 days old)
References	: http://marc.info/?l=linux-kernel&m=121814188805666&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11279
Subject		: 2.6.27-rc0 Power Bugs with HP/Compaq Laptops
Submitter	: Matt Parnell <mparnell@gmail.com>
Date		: 2008-08-07 14:57 (17 days old)
References	: http://marc.info/?l=linux-kernel&m=121812108031685&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11272
Subject		: BUG: parport_serial in 2.6.27-rc1 for NetMos Technology PCI 9835
Submitter	: Jaswinder Singh <jaswinderlinux@gmail.com>
Date		: 2008-08-05 15:12 (19 days old)
References	: http://marc.info/?l=linux-kernel&m=121794900319776&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11271
Subject		: BUG: fealnx in 2.6.27-rc1
Submitter	: Jaswinder Singh <jaswinderlinux@gmail.com>
Date		: 2008-08-05 14:58 (19 days old)
References	: http://marc.info/?l=linux-netdev&m=121794762016830&w=4
		  http://lkml.org/lkml/2008/8/10/98
Handled-By	: Francois Romieu <romieu@fr.zoreil.com>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11264
Subject		: Invalid op opcode in kernel/workqueue
Submitter	: Jean-Luc Coulon <jean.luc.coulon@gmail.com>
Date		: 2008-08-07 04:18 (17 days old)


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11237
Subject		: corrupt PMD after resume
Submitter	: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Date		: 2008-08-02 9:51 (22 days old)
References	: http://marc.info/?l=linux-kernel&m=121767073424952&w=4
Handled-By	: Hugh Dickins <hugh@veritas.com>
		  Jeremy Fitzhardinge <jeremy@goop.org>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11230
Subject		: Kconfig no longer outputs a .config with freshly updated defconfigs
Submitter	: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Date		: 2008-08-02 16:03 (22 days old)
References	: http://marc.info/?l=linux-kernel&m=121769306319391&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11224
Subject		: Only three cores found on quad-core machine.
Submitter	: Dave Jones <davej@redhat.com>
Date		: 2008-08-01 18:15 (23 days old)
References	: http://marc.info/?l=linux-kernel&m=121761475224719&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11220
Subject		: Screen stays black after resume
Submitter	: Nico Schottelius <nico@schottelius.org>
Date		: 2008-07-31 21:05 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121753882422899&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11219
Subject		: KVM modules break emergency reboot
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-08-01 20:25 (23 days old)
References	: http://marc.info/?l=linux-kernel&m=121762241105336&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11210
Subject		: libata badness
Submitter	: Kumar Gala <galak@kernel.crashing.org>
Date		: 2008-07-31 18:53 (24 days old)
References	: http://marc.info/?l=linux-ide&m=121753059307310&w=4
Handled-By	: Ben Dooks <ben-linux@fluff.org>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11209
Subject		: 2.6.27-rc1 process time accounting
Submitter	: Lukas Hejtmanek <xhejtman@ics.muni.cz>
Date		: 2008-07-31 10:43 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121750102917490&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11191
Subject		: 2.6.26-git8: spinlock lockup in c1e_idle()
Submitter	: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
Date		: 2008-07-24 03:22 (31 days old)
References	: http://lkml.org/lkml/2008/7/23/317
Handled-By	: Thomas Gleixner <tglx@linutronix.de>


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11141
Subject		: no battery or DC status - Dell i1501
Submitter	: Gu Rui <chaos.proton@gmail.com>
Date		: 2008-07-21 19:43 (34 days old)
Handled-By	: Zhao Yakui <yakui.zhao@intel.com>


Regressions with patches
------------------------

Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11413
Subject		: get_rtc_time() triggers NMI watchdog in hpet_rtc_interrupt()
Submitter	: Mikael Pettersson <mikpe@it.uu.se>
Date		: 2008-08-23 9:48 (1 days old)
References	: http://marc.info/?l=linux-kernel&m=121948503224161&w=4
Handled-By	: Ingo Molnar <mingo@elte.hu>
Patch		: http://marc.info/?l=linux-kernel&m=121950734922457&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11409
Subject		: build issue #564 for v2.6.27-rc4 : undefined reference to `NS8390p_init'
Submitter	: Toralf Förster <toralf.foerster@gmx.de>
Date		: 2008-08-22 8:33 (2 days old)
References	: http://marc.info/?l=linux-kernel&m=121939410214677&w=4
Handled-By	: Alan Cox <alan@lxorguk.ukuu.org.uk>
Patch		: http://marc.info/?l=linux-kernel&m=121943097320451&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11361
Subject		: my servers with nvidia mcp55 nic don't work with msi in second kernel by kexec
Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
Date		: 2008-08-17 6:25 (7 days old)
References	: http://marc.info/?l=linux-kernel&m=121895439927053&w=4
Handled-By	: Rafael J. Wysocki <rjw@sisk.pl>
Patch		: http://marc.info/?l=linux-kernel&m=121917167232014&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11360
Subject		: mpc8xxx_wdt.c doesn't build modular
Submitter	: Dave Jones <davej@redhat.com>
Date		: 2008-08-17 08:07 (7 days old)
References	: http://lkml.org/lkml/2008/8/12/465
Handled-By	: Anton Vorontsov <avorontsov@ru.mvista.com>
Patch		: http://lkml.org/lkml/2008/8/13/344


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11358
Subject		: net: forcedeth call restore mac addr in nv_shutdown path
Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
Date		: 2008-08-17 3:30 (7 days old)
References	: http://marc.info/?l=linux-kernel&m=121894389018584&w=4
Handled-By	: Yinghai Lu <yhlu.kernel@gmail.com>
Patch		: http://marc.info/?l=linux-kernel&m=121894389018584&w=4


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11276
Subject		: build error: CONFIG_OPTIMIZE_INLINING=y causes gcc 4.2 to do stupid things
Submitter	: Randy Dunlap <randy.dunlap@oracle.com>
Date		: 2008-08-06 17:18 (18 days old)
References	: http://marc.info/?l=linux-kernel&m=121804329014332&w=4
		  http://lkml.org/lkml/2008/7/22/353
Handled-By	: Bjorn Helgaas <bjorn.helgaas@hp.com>
Patch		: http://lkml.org/lkml/2008/7/22/364


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11254
Subject		: KVM: fix userspace ABI breakage
Submitter	: Adrian Bunk <bunk@kernel.org>
Date		: 21 Jul 2008 17:58:26 (0 days old)
References	: http://lkml.org/lkml/2008/7/21/197
Handled-By	: Adrian Bunk <bunk@kernel.org>
Patch		: http://lkml.org/lkml/2008/7/21/197


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11207
Subject		: VolanoMark regression with 2.6.27-rc1
Submitter	: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
Date		: 2008-07-31 3:20 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121747464114335&w=4
Handled-By	: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
		  Peter Zijlstra <a.p.zijlstra@chello.nl>
		  Dhaval Giani <dhaval@linux.vnet.ibm.com>
		  Miao Xie <miaox@cn.fujitsu.com>
Patch		: http://marc.info/?l=linux-kernel&m=121922991027344&w=4


For details, please visit the bug entries and follow the links given in
references.

As you can see, there is a Bugzilla entry for each of the listed regressions.
There also is a Bugzilla entry used for tracking the regressions from 2.6.26,
unresolved as well as resolved, at:

http://bugzilla.kernel.org/show_bug.cgi?id=11167

Please let me know if there are any Bugzilla entries that should be added to
the list in there.

Thanks,
Rafael

[Bug #11141] no battery or DC status - Dell i1501

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11141
Subject		: no battery or DC status - Dell i1501
Submitter	: Gu Rui <chaos.proton@gmail.com>
Date		: 2008-07-21 19:43 (34 days old)
Handled-By	: Zhao Yakui <yakui.zhao@intel.com>

[Bug #11207] VolanoMark regression with 2.6.27-rc1

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11207
Subject		: VolanoMark regression with 2.6.27-rc1
Submitter	: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
Date		: 2008-07-31 3:20 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121747464114335&w=4
Handled-By	: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
		  Peter Zijlstra <a.p.zijlstra@chello.nl>
		  Dhaval Giani <dhaval@linux.vnet.ibm.com>
		  Miao Xie <miaox@cn.fujitsu.com>
Patch		: http://marc.info/?l=linux-kernel&m=121922991027344&w=4

[Bug #11191] 2.6.26-git8: spinlock lockup in c1e_idle()

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11191
Subject		: 2.6.26-git8: spinlock lockup in c1e_idle()
Submitter	: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
Date		: 2008-07-24 03:22 (31 days old)
References	: http://lkml.org/lkml/2008/7/23/317
Handled-By	: Thomas Gleixner <tglx@linutronix.de>

[Bug #11220] Screen stays black after resume

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11220
Subject		: Screen stays black after resume
Submitter	: Nico Schottelius <nico@schottelius.org>
Date		: 2008-07-31 21:05 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121753882422899&w=4

[Bug #11209] 2.6.27-rc1 process time accounting

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11209
Subject		: 2.6.27-rc1 process time accounting
Submitter	: Lukas Hejtmanek <xhejtman@ics.muni.cz>
Date		: 2008-07-31 10:43 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121750102917490&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (24 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11219] KVM modules break emergency reboot

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11219
Subject		: KVM modules break emergency reboot
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-08-01 20:25 (23 days old)
References	: http://marc.info/?l=linux-kernel&m=121762241105336&w=4

[Bug #11210] libata badness

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11210
Subject		: libata badness
Submitter	: Kumar Gala <galak@kernel.crashing.org>
Date		: 2008-07-31 18:53 (24 days old)
References	: http://marc.info/?l=linux-ide&m=121753059307310&w=4
Handled-By	: Ben Dooks <ben-linux@fluff.org>

[Bug #11224] Only three cores found on quad-core machine.

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11224
Subject		: Only three cores found on quad-core machine.
Submitter	: Dave Jones <davej@redhat.com>
Date		: 2008-08-01 18:15 (23 days old)
References	: http://marc.info/?l=linux-kernel&m=121761475224719&w=4

[Bug #11237] corrupt PMD after resume

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11237
Subject		: corrupt PMD after resume
Submitter	: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Date		: 2008-08-02 9:51 (22 days old)
References	: http://marc.info/?l=linux-kernel&m=121767073424952&w=4
Handled-By	: Hugh Dickins <hugh@veritas.com>
		  Jeremy Fitzhardinge <jeremy@goop.org>

[Bug #11230] Kconfig no longer outputs a .config with freshly updated defconfigs

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11230
Subject		: Kconfig no longer outputs a .config with freshly updated defconfigs
Submitter	: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Date		: 2008-08-02 16:03 (22 days old)
References	: http://marc.info/?l=linux-kernel&m=121769306319391&w=4

[Bug #11264] Invalid op opcode in kernel/workqueue

[Rafael J. Wysocki]

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(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11264
Subject		: Invalid op opcode in kernel/workqueue
Submitter	: Jean-Luc Coulon <jean.luc.coulon@gmail.com>
Date		: 2008-08-07 04:18 (17 days old)

[Bug #11254] KVM: fix userspace ABI breakage

[Rafael J. Wysocki]

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of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11254
Subject		: KVM: fix userspace ABI breakage
Submitter	: Adrian Bunk <bunk@kernel.org>
Date		: 21 Jul 2008 17:58:26 (0 days old)
References	: http://lkml.org/lkml/2008/7/21/197
Handled-By	: Adrian Bunk <bunk@kernel.org>
Patch		: http://lkml.org/lkml/2008/7/21/197

[Bug #11271] BUG: fealnx in 2.6.27-rc1

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11271
Subject		: BUG: fealnx in 2.6.27-rc1
Submitter	: Jaswinder Singh <jaswinderlinux@gmail.com>
Date		: 2008-08-05 14:58 (19 days old)
References	: http://marc.info/?l=linux-netdev&m=121794762016830&w=4
		  http://lkml.org/lkml/2008/8/10/98
Handled-By	: Francois Romieu <romieu@fr.zoreil.com>

[Bug #11272] BUG: parport_serial in 2.6.27-rc1 for NetMos Technology PCI 9835

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11272
Subject		: BUG: parport_serial in 2.6.27-rc1 for NetMos Technology PCI 9835
Submitter	: Jaswinder Singh <jaswinderlinux@gmail.com>
Date		: 2008-08-05 15:12 (19 days old)
References	: http://marc.info/?l=linux-kernel&m=121794900319776&w=4

[Bug #11279] 2.6.27-rc0 Power Bugs with HP/Compaq Laptops

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11279
Subject		: 2.6.27-rc0 Power Bugs with HP/Compaq Laptops
Submitter	: Matt Parnell <mparnell@gmail.com>
Date		: 2008-08-07 14:57 (17 days old)
References	: http://marc.info/?l=linux-kernel&m=121812108031685&w=4

[Bug #11282] Please fix x86 defconfig regression

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11282
Subject		: Please fix x86 defconfig regression
Submitter	: Andi Kleen <andi@firstfloor.org>
Date		: 2008-08-07 20:46 (17 days old)
References	: http://marc.info/?l=linux-kernel&m=121814188805666&w=4

[Bug #11276] build error: CONFIG_OPTIMIZE_INLINING=y causes gcc 4.2 to do stupid things

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11276
Subject		: build error: CONFIG_OPTIMIZE_INLINING=y causes gcc 4.2 to do stupid things
Submitter	: Randy Dunlap <randy.dunlap@oracle.com>
Date		: 2008-08-06 17:18 (18 days old)
References	: http://marc.info/?l=linux-kernel&m=121804329014332&w=4
		  http://lkml.org/lkml/2008/7/22/353
Handled-By	: Bjorn Helgaas <bjorn.helgaas@hp.com>
Patch		: http://lkml.org/lkml/2008/7/22/364

[Bug #11336] 2.6.27-rc2:stall while mounting root fs

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11336
Subject		: 2.6.27-rc2:stall while mounting root fs
Submitter	: Torsten Kaiser <just.for.lkml@googlemail.com>
Date		: 2008-08-12 12:37 (12 days old)
References	: http://marc.info/?l=linux-kernel&m=121854484015909&w=4

[Bug #11334] myri10ge: use ioremap_wc: compilation failure on ARM

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11334
Subject		: myri10ge: use ioremap_wc: compilation failure on ARM
Submitter	: Martin Michlmayr <tbm@cyrius.com>
Date		: 2008-08-10 11:25 (14 days old)
References	: http://marc.info/?l=linux-netdev&m=121836771727632&w=2

[Bug #11308] tbench regression on each kernel release from 2.6.22 -> 2.6.28

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11308
Subject		: tbench regression on each kernel release from 2.6.22 -> 2.6.28
Submitter	: Christoph Lameter <cl@linux-foundation.org>
Date		: 2008-08-11 18:36 (13 days old)
References	: http://marc.info/?l=linux-kernel&m=121847986119495&w=4

[Bug #11335] 2.6.27-rc2-git5 BUG: unable to handle kernel paging request

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11335
Subject		: 2.6.27-rc2-git5 BUG: unable to handle kernel paging request
Submitter	: Randy Dunlap <randy.dunlap@oracle.com>
Date		: 2008-08-12 4:18 (12 days old)
References	: http://marc.info/?l=linux-kernel&m=121851477201960&w=4
		  http://lkml.org/lkml/2008/8/16/274
Handled-By	: Hugh Dickins <hugh@veritas.com>

[Bug #11340] LTP overnight run resulted in unusable box

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11340
Subject		: LTP overnight run resulted in unusable box
Submitter	: Alexey Dobriyan <adobriyan@gmail.com>
Date		: 2008-08-13 9:24 (11 days old)
References	: http://marc.info/?l=linux-kernel&m=121861951902949&w=4

[Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11342
Subject		: Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected
Submitter	: Alan D. Brunelle <Alan.Brunelle@hp.com>
Date		: 2008-08-13 23:03 (11 days old)
References	: http://marc.info/?l=linux-kernel&m=121866876027629&w=4
Handled-By	: Andrew Morton <akpm@linux-foundation.org>

[Bug #11343] SATA Cold Boot Problems with 2.6.27-rc[23] on nVidia 680i

[Rafael J. Wysocki]

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(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11343
Subject		: SATA Cold Boot Problems with 2.6.27-rc[23] on nVidia 680i
Submitter	: Manny Maxwell <mannymax@mannymax.net>
Date		: 2008-08-14 4:16 (10 days old)
References	: http://marc.info/?l=linux-kernel&m=121868782917600&w=4

[Bug #11355] Regression in 2.6.27-rc2 when cross-building the kernel

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11355
Subject		: Regression in 2.6.27-rc2 when cross-building the kernel
Submitter	: Larry Finger <Larry.Finger@lwfinger.net>
Date		: 2008-08-16 2:38 (8 days old)
References	: http://marc.info/?l=linux-kernel&m=121885432118368&w=4

[Bug #11354] AMD Elan regression with 2.6.27-rc3

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11354
Subject		: AMD Elan regression with 2.6.27-rc3
Submitter	: Sean Young <sean@mess.org>
Date		: 2008-08-15 18:37 (9 days old)
References	: http://marc.info/?l=linux-kernel&m=121882578430056&w=4

[Bug #11356] Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11356
Subject		: Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'
Submitter	: Frans Pop <elendil@planet.nl>
Date		: 2008-08-16 19:11 (8 days old)
References	: http://marc.info/?l=linux-kernel&m=121891396320127&w=4

[Bug #11358] net: forcedeth call restore mac addr in nv_shutdown path

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11358
Subject		: net: forcedeth call restore mac addr in nv_shutdown path
Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
Date		: 2008-08-17 3:30 (7 days old)
References	: http://marc.info/?l=linux-kernel&m=121894389018584&w=4
Handled-By	: Yinghai Lu <yhlu.kernel@gmail.com>
Patch		: http://marc.info/?l=linux-kernel&m=121894389018584&w=4

[Bug #11357] Can not boot up with zd1211rw USB-Wlan Stick

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11357
Subject		: Can not boot up with zd1211rw USB-Wlan Stick
Submitter	: uwe <kender@freenet.de>
Date		: 2008-08-16 14:17 (8 days old)

[Bug #11380] lockdep warning: cpu_add_remove_lock at:cpu_maps_update_begin+0x14/0x16

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11380
Subject		: lockdep warning: cpu_add_remove_lock at:cpu_maps_update_begin+0x14/0x16
Submitter	: Ingo Molnar <mingo@elte.hu>
Date		: 2008-08-20 6:44 (4 days old)
References	: http://marc.info/?l=linux-kernel&m=121921480931970&w=4

[Bug #11379] char/tpm: tpm_infineon no longer loaded for HP 2510p laptop

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11379
Subject		: char/tpm: tpm_infineon no longer loaded for HP 2510p laptop
Submitter	: Frans Pop <elendil@planet.nl>
Date		: 2008-08-18 13:40 (6 days old)
References	: http://marc.info/?l=linux-kernel&m=121906698213329&w=4
Handled-By	: Bjorn Helgaas <bjorn.helgaas@hp.com>

[Bug #11360] mpc8xxx_wdt.c doesn't build modular

[Rafael J. Wysocki]

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from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11360
Subject		: mpc8xxx_wdt.c doesn't build modular
Submitter	: Dave Jones <davej@redhat.com>
Date		: 2008-08-17 08:07 (7 days old)
References	: http://lkml.org/lkml/2008/8/12/465
Handled-By	: Anton Vorontsov <avorontsov@ru.mvista.com>
Patch		: http://lkml.org/lkml/2008/8/13/344

[Bug #11361] my servers with nvidia mcp55 nic don't work with msi in second kernel by kexec

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11361
Subject		: my servers with nvidia mcp55 nic don't work with msi in second kernel by kexec
Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
Date		: 2008-08-17 6:25 (7 days old)
References	: http://marc.info/?l=linux-kernel&m=121895439927053&w=4
Handled-By	: Rafael J. Wysocki <rjw@sisk.pl>
Patch		: http://marc.info/?l=linux-kernel&m=121917167232014&w=4

[Bug #11388] 2.6.27-rc3 warns about MTRR range; only 3 of 16gb of memory is usable

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11388
Subject		: 2.6.27-rc3 warns about MTRR range; only 3 of 16gb of memory is usable
Submitter	: Joshua Hoblitt <j_kernel@hoblitt.com>
Date		: 2008-08-20 17:38 (4 days old)

[Bug #11382] e1000e: 2.6.27-rc1 corrupts EEPROM/NVM

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11382
Subject		: e1000e: 2.6.27-rc1 corrupts EEPROM/NVM
Submitter	: David Vrabel <david.vrabel@csr.com>
Date		: 2008-08-08 10:47 (16 days old)
References	: http://marc.info/?l=linux-kernel&m=121819267211679&w=4

[Bug #11401] pktcdvd: BUG, NULL pointer dereference in pkt_ioctl, bisected

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11401
Subject		: pktcdvd: BUG, NULL pointer dereference in pkt_ioctl, bisected
Submitter	: Laurent Riffard <laurent.riffard@free.fr>
Date		: 2008-08-22 08:16 (2 days old)

[Bug #11398] hda_intel: IRQ timing workaround is activated for card #0. Suggest a bigger bdl_pos_adj.

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11398
Subject		: hda_intel: IRQ timing workaround is activated for card #0. Suggest a bigger bdl_pos_adj.
Submitter	: Frans Pop <elendil@planet.nl>
Date		: 2008-08-21 17:17 (3 days old)

[Bug #11405] 2.6.27-rc3 segfault on cold boot; not on warm boot.

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11405
Subject		: 2.6.27-rc3 segfault on cold boot; not on warm boot.
Submitter	: David Greaves <david@dgreaves.com>
Date		: 2008-08-21 9:45 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121931198904777&w=4

[Bug #11404] BUG: in 2.6.23-rc3-git7 in do_cciss_intr

[Rafael J. Wysocki]

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The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11404
Subject		: BUG: in 2.6.23-rc3-git7 in do_cciss_intr
Submitter	: rdunlap <randy.dunlap@oracle.com>
Date		: 2008-08-21 5:52 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121929819616273&w=4
		  http://marc.info/?l=linux-kernel&m=121932889105368&w=4
Handled-By	: Miller, Mike (OS Dev) <Mike.Miller@hp.com>
		  James Bottomley <James.Bottomley@hansenpartnership.com>

[Bug #11406] patch "x86: MOVE PCI IO ECS code to x86/pci" breaks CPU hotplug

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11406
Subject		: patch "x86: MOVE PCI IO ECS code to x86/pci" breaks CPU hotplug
Submitter	: Jan Beulich <jbeulich@novell.com>
Date		: 2008-08-21 12:59 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121932366326572&w=4
Handled-By	: Ingo Molnar <mingo@elte.hu>
		  Robert Richter <robert.richter@amd.com>

[Bug #11403] 2.6.27-rc2 USB suspend regression

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11403
Subject		: 2.6.27-rc2 USB suspend regression
Submitter	: Jeremy Fitzhardinge <jeremy@goop.org>
Date		: 2008-08-20 20:48 (4 days old)
References	: http://marc.info/?l=linux-kernel&m=121926536103630&w=4
Handled-By	: Alan Stern <stern@rowland.harvard.edu>

[Bug #11402] skbuff bug?

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11402
Subject		: skbuff bug?
Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
Date		: 2008-08-21 3:56 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121929102707658&w=4

[Bug #11413] get_rtc_time() triggers NMI watchdog in hpet_rtc_interrupt()

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11413
Subject		: get_rtc_time() triggers NMI watchdog in hpet_rtc_interrupt()
Submitter	: Mikael Pettersson <mikpe@it.uu.se>
Date		: 2008-08-23 9:48 (1 days old)
References	: http://marc.info/?l=linux-kernel&m=121948503224161&w=4
Handled-By	: Ingo Molnar <mingo@elte.hu>
Patch		: http://marc.info/?l=linux-kernel&m=121950734922457&w=4

[Bug #11409] build issue #564 for v2.6.27-rc4 : undefined reference to `NS8390p_init'

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11409
Subject		: build issue #564 for v2.6.27-rc4 : undefined reference to `NS8390p_init'
Submitter	: Toralf Förster <toralf.foerster@gmx.de>
Date		: 2008-08-22 8:33 (2 days old)
References	: http://marc.info/?l=linux-kernel&m=121939410214677&w=4
Handled-By	: Alan Cox <alan@lxorguk.ukuu.org.uk>
Patch		: http://marc.info/?l=linux-kernel&m=121943097320451&w=4

[Bug #11410] SLUB list_lock vs obj_hash.lock...

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11410
Subject		: SLUB list_lock vs obj_hash.lock...
Submitter	: Daniel J Blueman <daniel.blueman@gmail.com>
Date		: 2008-08-22 21:48 (2 days old)
References	: http://marc.info/?l=linux-kernel&m=121944176609042&w=4

[Bug #11407] suspend: unable to handle kernel paging request

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11407
Subject		: suspend: unable to handle kernel paging request
Submitter	: Vegard Nossum <vegard.nossum@gmail.com>
Date		: 2008-08-21 17:28 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121933974928881&w=4
Handled-By	: Rafael J. Wysocki <rjw@sisk.pl>
		  Pekka Enberg <penberg@cs.helsinki.fi>
		  Pavel Machek <pavel@suse.cz>

[Bug #11414] Random crashes with 2.6.27-rc3 on PPC

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11414
Subject		: Random crashes with 2.6.27-rc3 on PPC
Submitter	: Michael Buesch <mb@bu3sch.de>
Date		: 2008-08-23 14:10 (1 days old)
References	: http://marc.info/?l=linux-kernel&m=121950076812616&w=4

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> 
> The following bug entry is on the current list of known regressions
> from 2.6.26.  Please verify if it still should be listed and let me know
> (either way).
> 
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11342
> Subject		: Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected
> Submitter	: Alan D. Brunelle <Alan.Brunelle@hp.com>
> Date		: 2008-08-13 23:03 (11 days old)
> References	: http://marc.info/?l=linux-kernel&m=121866876027629&w=4
> Handled-By	: Andrew Morton <akpm@linux-foundation.org>

This one makes no sense. It's triggering a BUG_ON(in_interrupt()), but 
then the call chain shows that there is no interrupt going on.

Also, the bisection is senseless - there's a trivial change wrt 
"do_one_initcall()" that got merged, but everything else is trivial about 
lguest and has nothing to do with the whole CPU-init thing. But if it was 
that initcall one, then "git bisect" woul have pointed to it, not the 
merge. And the merge itself had no conflicts or anything else going on..

The fact that it came and went later also implies that it's probably just 
some timing-dependent thing or some subtle memory corruption, making the 
bisection result even less likely to be exact.

But I'm adding Arjan and Rusty to the Cc, because that merge was takign 
Rusty's branch, and the "do_one_initcall()" is Arjan's commit. Since 
undoing that merge apparently does fix it, I'm wondering if something 
there just does end up triggering the problem.

The do_one_commit() thing _is_ in the path of sys_init_module(), so it 
_is_ at least somewhat relevant from an oops standpoint. 

One thing the "do_one_commit()" thing does is to put more pressure on the 
stack due to that whole buffer for the printk's going on.

Alan, can you try 
 - seeing how consistent it is with one kernel (ie boot a known-bad kernel 
   a few times just to see if it really is 100% consistent)
 - try enabling 'initcall_debug' on the kernel command line, to (a) see 
   the new code actually do something and (b) see what it is actually 
   calling just before.

Hmm..

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Arjan van de Ven]

Linus Torvalds wrote:
> 
> On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
>> The following bug entry is on the current list of known regressions
>> from 2.6.26.  Please verify if it still should be listed and let me know
>> (either way).
>>
>>
>> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11342
>> Subject		: Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected
>> Submitter	: Alan D. Brunelle <Alan.Brunelle@hp.com>
>> Date		: 2008-08-13 23:03 (11 days old)
>> References	: http://marc.info/?l=linux-kernel&m=121866876027629&w=4
>> Handled-By	: Andrew Morton <akpm@linux-foundation.org>
> 
> This one makes no sense. It's triggering a BUG_ON(in_interrupt()), but 
> then the call chain shows that there is no interrupt going on.
> 
> Also, the bisection is senseless - there's a trivial change wrt 
> "do_one_initcall()" that got merged, but everything else is trivial about 
> lguest and has nothing to do with the whole CPU-init thing. But if it was 
> that initcall one, then "git bisect" woul have pointed to it, not the 
> merge. And the merge itself had no conflicts or anything else going on..
> 
> The fact that it came and went later also implies that it's probably just 
> some timing-dependent thing or some subtle memory corruption, making the 
> bisection result even less likely to be exact.
> 
> But I'm adding Arjan and Rusty to the Cc, because that merge was takign 
> Rusty's branch, and the "do_one_initcall()" is Arjan's commit. Since 
> undoing that merge apparently does fix it, I'm wondering if something 
> there just does end up triggering the problem.
> 
> The do_one_commit() thing _is_ in the path of sys_init_module(), so it 
> _is_ at least somewhat relevant from an oops standpoint. 
> 
> One thing the "do_one_commit()" thing does is to put more pressure on the 
> stack due to that whole buffer for the printk's going on.

but it's 64 bit.. with 8Kb stack and separate irq stacks. I'd be surprised if we blow that this easily.
the trace is a tad long with a long ACPI call chain.

Wonder what gcc is in use?
(newer ones tend to be a ton better... but maybe Alex is using a really old one)

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Sat, 23 Aug 2008, Linus Torvalds wrote:
> 
> This one makes no sense. It's triggering a BUG_ON(in_interrupt()), but 
> then the call chain shows that there is no interrupt going on.

Ahh, later in that thread there's another totally unrelated oops in 
debug_mutex_add_waiter().

I'd guess that it is really wild pointer corrupting memory, quite possibly 
due to a double free or something like that. Alan - it would be good to 
run with DEBUG_PAGE_ALLOC and SLUB debugging etc if you don't already do 
that?

		Linus

Re: [Bug #11210] libata badness

[Jeff Garzik]

Rafael J. Wysocki wrote:
> This message has been generated automatically as a part of a report
> of recent regressions.
> 
> The following bug entry is on the current list of known regressions
> from 2.6.26.  Please verify if it still should be listed and let me know
> (either way).
> 
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11210
> Subject		: libata badness
> Submitter	: Kumar Gala <galak@kernel.crashing.org>
> Date		: 2008-07-31 18:53 (24 days old)
> References	: http://marc.info/?l=linux-ide&m=121753059307310&w=4
> Handled-By	: Ben Dooks <ben-linux@fluff.org>


FWIW,

http://marc.info/?l=linux-kernel&m=121754161727539&w=4

So IMO handled-by is Kumar?

Re: [Bug #11271] BUG: fealnx in 2.6.27-rc1

[Jeff Garzik]

Rafael J. Wysocki wrote:
> This message has been generated automatically as a part of a report
> of recent regressions.
> 
> The following bug entry is on the current list of known regressions
> from 2.6.26.  Please verify if it still should be listed and let me know
> (either way).
> 
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11271
> Subject		: BUG: fealnx in 2.6.27-rc1
> Submitter	: Jaswinder Singh <jaswinderlinux@gmail.com>
> Date		: 2008-08-05 14:58 (19 days old)
> References	: http://marc.info/?l=linux-netdev&m=121794762016830&w=4
> 		  http://lkml.org/lkml/2008/8/10/98
> Handled-By	: Francois Romieu <romieu@fr.zoreil.com>


Jaswinder, does reverting 28cd4289abc2c8db90344ee4ff064a9bdf086fdf help?

That's the only material change to fealnx itself in years.

If not, any chance you could bisect this problem, and add more info to 
the bug?

Re: [Bug #11343] SATA Cold Boot Problems with 2.6.27-rc[23] on nVidia 680i

[Jeff Garzik]

Rafael J. Wysocki wrote:
> This message has been generated automatically as a part of a report
> of recent regressions.
> 
> The following bug entry is on the current list of known regressions
> from 2.6.26.  Please verify if it still should be listed and let me know
> (either way).
> 
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11343
> Subject		: SATA Cold Boot Problems with 2.6.27-rc[23] on nVidia 680i
> Submitter	: Manny Maxwell <mannymax@mannymax.net>
> Date		: 2008-08-14 4:16 (10 days old)
> References	: http://marc.info/?l=linux-kernel&m=121868782917600&w=4


hmmmm.  Looking at changes between the two csets listed in the email 
(623fa57..8f616cd), all of them are driver-specific and unrelated to 
Manny's hardware except for

	commit 2486fa561a3192bbbec39c7feef87a1e07bd6342
	Author: Tejun Heo <tj@kernel.org>
	Date:   Thu Jul 31 07:52:40 2008 +0900

	    libata: update atapi disable handling

So you could try to revert that and see what happens.  But given that 
small range of changes, it really seems like something else, maybe in 
the PCI subsystem (random guess).

Looking at the entire kernel, nothing jumps out, either.  Its mostly fs 
updates (ext4, xfs), a networking update, an ARM update, and a libata 
update.

Also, some reset-related fixes just went in, so re-testing the latest 
-git would be helpful as well.

	Jeff

Re: [Bug #11356] Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'

[Frans Pop]

On Saturday 23 August 2008, Rafael J. Wysocki wrote:
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11356
> Subject	: Linux 2.6.27-rc3 - build failure: undefined reference to
> 		  `.lockdep_count_forward_deps'
> Submitter	: Frans Pop <elendil@planet.nl> 
> Date		: 2008-08-16 19:11 (8 days old)
> References	: http://marc.info/?l=linux-kernel&m=121891396320127&w=4

Fixed as per: http://marc.info/?l=linux-kernel&m=121898767530602&w=4
Adrian mentioned that he'd closed the bug, but apparently not.

Re: [Bug #11379] char/tpm: tpm_infineon no longer loaded for HP 2510p laptop

[Frans Pop]

On Saturday 23 August 2008, Rafael J. Wysocki wrote:
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11379
> Subject	: char/tpm: tpm_infineon no longer loaded for HP 2510p laptop
> Submitter	: Frans Pop <elendil@planet.nl>
> Date		: 2008-08-18 13:40 (6 days old)
> References	: http://marc.info/?l=linux-kernel&m=121906698213329&w=4
> Handled-By	: Bjorn Helgaas <bjorn.helgaas@hp.com>

Fixed with:
commit 5e4c6564c95ce127beeefe75e15cd11c93487436
Author: Kay Sievers <kay.sievers@vrfy.org>
Date:   Thu Aug 21 15:28:56 2008 +0200

    pnp: fix "add acpi:* modalias entries"

Re: [Bug #11334] myri10ge: use ioremap_wc: compilation failure on ARM

[Martin Michlmayr]

* Rafael J. Wysocki <rjw@sisk.pl> [2008-08-23 20:10]:
> This message has been generated automatically as a part of a report
> of recent regressions.
> 
> The following bug entry is on the current list of known regressions
> from 2.6.26.  Please verify if it still should be listed and let me know
> (either way).

Yes, this is still there.
-- 
Martin Michlmayr
http://www.cyrius.com/

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11405
> Subject		: 2.6.27-rc3 segfault on cold boot; not on warm boot.
> Submitter	: David Greaves <david@dgreaves.com>
> Date		: 2008-08-21 9:45 (3 days old)
> References	: http://marc.info/?l=linux-kernel&m=121931198904777&w=4

It would be good to have some kind of bisection of this one, because it 
looks pretty odd. Also, google doesn't find anybody else seeing that 
"segfault at ffffffbf", even though it seems to be very consistent for 
David. So I don't think we'll be able to even _guess_ where it is without 
some more information about exactly when it started happening.

Since it's present in 2.6.26 too, it's clearly not a regression from that 
one, but perhaps more importantly, since it's apparently an old one I'd 
have expected more reports like this if it was some common problem. And 
the warm-vs-cold-boot thing makes me think it's some hardware setup issue. 

Possibly the disk controller, possibly the CPU (eg some MTRR/PAT 
setup issue or TLB thing). But the dmesg's are all from late enough at 
boot that I can't even tell what disk controller it is (except that it is 
SATA), nor can I tell what CPU it is.

But again, if it was some MTRR/PAT issue, I'd expect a _lot_ more reports 
of this. 

MD/XFS sounds unlikely, since they should have absolutely nothing that 
could possibly matter for cold/hot boot.

			Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11410
> Subject		: SLUB list_lock vs obj_hash.lock...
> Submitter	: Daniel J Blueman <daniel.blueman@gmail.com>
> Date		: 2008-08-22 21:48 (2 days old)
> References	: http://marc.info/?l=linux-kernel&m=121944176609042&w=4

This one now has a suggested patch for Daniel to try from Vegard, but no 
reply yet:

	http://marc.info/?l=linux-kernel&m=121946972307110&w=4

Vegard, I think your patch is a bit odd, though. The result of your patch 
is

 - first loop:

	hlist_for_each_entry_safe(obj, node, tmp, &db->list, node) {
		hlist_del(&obj->node);
		hlist_add_head(&obj->node, &freelist);
	}

   and quite frankly, I don't see what the difference between that and a 
   something like a simple

	struct hlist_node *first = bd->list.first;
	if (first) {
		bd->list.first = NULL;
		first->pprev = &first;
	}

   really is?

I dunno. We don't have list splicing ops for the hlist things.

		Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11401
> Subject		: pktcdvd: BUG, NULL pointer dereference in pkt_ioctl, bisected
> Submitter	: Laurent Riffard <laurent.riffard@free.fr>
> Date		: 2008-08-22 08:16 (2 days old)

This one looks irritating.

It's bisected to 5b6155ee70e9c4d2ad7e6f514c8eee06e2711c3a ("pktcdvd: push 
BKL down into driver"), but the problem goes deeper than that.

The "unlocked" ioctl's do not get a "struct inode *" pointer, they _only_ 
get the "struct file *". And this is very much historical usage, where 
some internal functions only passed in the inode (good or not, whatever).

And ioctl_by_bdev() doesn't have a "struct file *" and has depended on 
passing in a NUMM "struct file *" and its own "struct inode *", and 
expects the ioctl's to just use that instead. But the unlocked ioctl just 
drops it on the floor, and uses just the (unusable) file pointer.

Grr.

And some other cases (like pkt_ioctl() itself) that simply pass in a 
_different_ inode than the file itself is attached to. It does

	blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);

where "file" points to the pkt_ioctl thing, but "inode" points to the 
inode "behind" the pkt interface.

Double grr.

I really think the only sane model is to literally make "unlocked_ioctl()" 
have the same calling convention as the old "ioctl()" thing had, and pass 
in both file * and inode *. It was a stupid "cleanup" to try to have a 
simpler interface for the unlocked version. Having two different models, 
where we have actually _depended_ on the old model and then are trying to 
convert to a (weaker) new model, is not a good idea.

The alternative is to do this _only_ for the blkdev_ioctl's, and have 
those only take the "inode *", and then create a new fake "struct file *" 
to go with it, regardless of what "struct file" was passed in (exactly 
because the blockdev ones really think that the inode is the important 
part).

Hmm?

We need to fix this.

		Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Vegard Nossum]

On Sun, Aug 24, 2008 at 8:03 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
>
> On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
>>
>> Bug-Entry     : http://bugzilla.kernel.org/show_bug.cgi?id=11410
>> Subject               : SLUB list_lock vs obj_hash.lock...
>> Submitter     : Daniel J Blueman <daniel.blueman@gmail.com>
>> Date          : 2008-08-22 21:48 (2 days old)
>> References    : http://marc.info/?l=linux-kernel&m=121944176609042&w=4
>
> This one now has a suggested patch for Daniel to try from Vegard, but no
> reply yet:
>
>        http://marc.info/?l=linux-kernel&m=121946972307110&w=4
>

Hi!

> Vegard, I think your patch is a bit odd, though. The result of your patch
> is
>
>  - first loop:
>
>        hlist_for_each_entry_safe(obj, node, tmp, &db->list, node) {
>                hlist_del(&obj->node);
>                hlist_add_head(&obj->node, &freelist);
>        }
>
>   and quite frankly, I don't see what the difference between that and a
>   something like a simple
>
>        struct hlist_node *first = bd->list.first;
>        if (first) {
>                bd->list.first = NULL;
>                first->pprev = &first;
>        }
>
>   really is?
>
> I dunno. We don't have list splicing ops for the hlist things.

Hm.

I haven't really used the hlists before, so my first instinct was to
do what is obvious. That's also why I put the XXX comment. Other than
that, I guess open-coding list ops is also not very good programming
practice? :-)

But... feel free to submit your own patch. Oh, what am I saying.


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11354
> Subject		: AMD Elan regression with 2.6.27-rc3
> Submitter	: Sean Young <sean@mess.org>
> Date		: 2008-08-15 18:37 (9 days old)
> References	: http://marc.info/?l=linux-kernel&m=121882578430056&w=4

Peter? Ingo? Alok?

This _looks_ like it might be due to "x86: merge the TSC cpu-freq code" 
thing by Alok, where we do this:

	+static struct notifier_block time_cpufreq_notifier_block = {
	+       .notifier_call  = time_cpufreq_notifier
	+};
	+
	+static int __init cpufreq_tsc(void)
	+{
	+       cpufreq_register_notifier(&time_cpufreq_notifier_block,
	+                               CPUFREQ_TRANSITION_NOTIFIER);
	+       return 0;
	+}

but that's just _insane_ if the CPU doesn't even support TSC to begin 
with. Also, in the actual time_cpufreq_notifier(), we do:

	if (cpu_has(&cpu_data(freq->cpu), X86_FEATURE_CONSTANT_TSC))
		return 0;

and this is stupid because:

 (a) if the CPU has no TSC at all, then it sure as hell won't have a 
     _constant_ one, so we'll actually continue into the function.

 (b) and why the hell is this done at run-time in the notifier, and not in 
     the "cpufreq_tsc" init function? If anybody mixes totally different 
     kinds of CPU's in SMP, they deserve whatever they want.

so why is the patch not something like the appended?

Sean, does this make any difference for you?

		Linus

---
 arch/x86/kernel/tsc.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 46af716..9bed5ca 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -325,6 +325,10 @@ static struct notifier_block time_cpufreq_notifier_block = {
 
 static int __init cpufreq_tsc(void)
 {
+	if (!cpu_has_tsc)
+		return 0;
+	if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
+		return 0;
 	cpufreq_register_notifier(&time_cpufreq_notifier_block,
 				CPUFREQ_TRANSITION_NOTIFIER);
 	return 0;

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Sun, 24 Aug 2008, Vegard Nossum wrote:
> 
> I haven't really used the hlists before, so my first instinct was to
> do what is obvious.

I do agree that the hlist versions aren't very nice in this regard. The 
regular lists are much better at moving lists around.

> Other than that, I guess open-coding list ops is also not very good 
> programming practice? :-)

Agreed. It would be better if the people who use hlists most (I think that 
would be networking) would think about this.

> But... feel free to submit your own patch. Oh, what am I saying.

Silly boy. Next you'll ask me to _test_ any patches I send out.

Anyway, I think your patch is likely fine, I just thought it looked a bit 
odd to have a loop to move a list from one head pointer to another.

But regardless, it would need some testing. Daniel?

			Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11356
> Subject		: Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'
> Submitter	: Frans Pop <elendil@planet.nl>
> Date		: 2008-08-16 19:11 (8 days old)
> References	: http://marc.info/?l=linux-kernel&m=121891396320127&w=4

Hmm. Wasn't this already confirmed to be fixed by commit
df60a8441866153d691ae69b77934904c2de5e0d? 

At least Adrian sent out an email saying "Confirmed, bug closed.", but 
bugzilla seems to disagree and still show it as open.

		Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Adrian Bunk]

On Sun, Aug 24, 2008 at 12:03:37PM -0700, Linus Torvalds wrote:
> 
> 
> On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> > 
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11356
> > Subject		: Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'
> > Submitter	: Frans Pop <elendil@planet.nl>
> > Date		: 2008-08-16 19:11 (8 days old)
> > References	: http://marc.info/?l=linux-kernel&m=121891396320127&w=4
> 
> Hmm. Wasn't this already confirmed to be fixed by commit
> df60a8441866153d691ae69b77934904c2de5e0d? 
> 
> At least Adrian sent out an email saying "Confirmed, bug closed.", but 
> bugzilla seems to disagree and still show it as open.

There were two different reports, Rafael opened a bug for each, and I 
missed that there were two open bugs for the same issue.

The one I closed was #11344.

I've now closed #11356 as a duplicate of #11344.

> 		Linus

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[David Greaves]

Linus Torvalds wrote:
> 
> On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
>> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11405
>> Subject		: 2.6.27-rc3 segfault on cold boot; not on warm boot.
>> Submitter	: David Greaves <david@dgreaves.com>
>> Date		: 2008-08-21 9:45 (3 days old)
>> References	: http://marc.info/?l=linux-kernel&m=121931198904777&w=4
> 
> It would be good to have some kind of bisection of this one, because it 
> looks pretty odd. Also, google doesn't find anybody else seeing that 
> "segfault at ffffffbf", even though it seems to be very consistent for 
> David. So I don't think we'll be able to even _guess_ where it is without 
> some more information about exactly when it started happening.
> 
> Since it's present in 2.6.26 too, it's clearly not a regression from that 
> one, but perhaps more importantly, since it's apparently an old one I'd 
> have expected more reports like this if it was some common problem. And 
> the warm-vs-cold-boot thing makes me think it's some hardware setup issue.
> 
> Possibly the disk controller, possibly the CPU (eg some MTRR/PAT 
> setup issue or TLB thing). But the dmesg's are all from late enough at 
> boot that I can't even tell what disk controller it is (except that it is 
> SATA), nor can I tell what CPU it is.
> 
> But again, if it was some MTRR/PAT issue, I'd expect a _lot_ more reports 
> of this. 

OK, that all makes sense.

Given that I'll manage at best 1 bisect/day with a reasonable chance of data
corruption and hardware intermittency screwing it all up I thought it best to
ask first in case there was another debug approach that could work. However
since it does indeed sounds somewhat hardware related and it's an isolated
problem for my wife (as opposed to a problem that others are having too) then I
think she deserves a new machine...

Thanks for the impetus to cheer her up ;)

David
PS if anyone really is interested then I am happy to try the bisection once I've
moved her to a new box; otherwise I'm happy to close this.

Re: [Bug #11254] KVM: fix userspace ABI breakage

[Adrian Bunk]

On Sat, Aug 23, 2008 at 08:10:16PM +0200, Rafael J. Wysocki wrote:
> This message has been generated automatically as a part of a report
> of recent regressions.
> 
> The following bug entry is on the current list of known regressions
> from 2.6.26.  Please verify if it still should be listed and let me know
> (either way).
> 
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11254
> Subject		: KVM: fix userspace ABI breakage
> Submitter	: Adrian Bunk <bunk@kernel.org>
> Date		: 21 Jul 2008 17:58:26 (0 days old)
> References	: http://lkml.org/lkml/2008/7/21/197
> Handled-By	: Adrian Bunk <bunk@kernel.org>
> Patch		: http://lkml.org/lkml/2008/7/21/197

The discussion in Bugzilla whether it is a regression at all can be 
condensed to the following question:

Can a struct that is part of the 2.6.26 userspace headers be defined to 
be part of an "experimental ABI" and therefore be changed?

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11210] libata badness

[Rafael J. Wysocki]

On Sunday, 24 of August 2008, Jeff Garzik wrote:
> Rafael J. Wysocki wrote:
> > This message has been generated automatically as a part of a report
> > of recent regressions.
> > 
> > The following bug entry is on the current list of known regressions
> > from 2.6.26.  Please verify if it still should be listed and let me know
> > (either way).
> > 
> > 
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11210
> > Subject		: libata badness
> > Submitter	: Kumar Gala <galak@kernel.crashing.org>
> > Date		: 2008-07-31 18:53 (24 days old)
> > References	: http://marc.info/?l=linux-ide&m=121753059307310&w=4
> > Handled-By	: Ben Dooks <ben-linux@fluff.org>
> 
> 
> FWIW,
> 
> http://marc.info/?l=linux-kernel&m=121754161727539&w=4
> 
> So IMO handled-by is Kumar?

OK

Re: [Bug #11334] myri10ge: use ioremap_wc: compilation failure on ARM

[Rafael J. Wysocki]

On Sunday, 24 of August 2008, Martin Michlmayr wrote:
> * Rafael J. Wysocki <rjw@sisk.pl> [2008-08-23 20:10]:
> > This message has been generated automatically as a part of a report
> > of recent regressions.
> > 
> > The following bug entry is on the current list of known regressions
> > from 2.6.26.  Please verify if it still should be listed and let me know
> > (either way).
> 
> Yes, this is still there.

Thanks for the update.

Rafael

Re: [Bug #11356] Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'

[Rafael J. Wysocki]

On Sunday, 24 of August 2008, Frans Pop wrote:
> On Saturday 23 August 2008, Rafael J. Wysocki wrote:
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11356
> > Subject	: Linux 2.6.27-rc3 - build failure: undefined reference to
> > 		  `.lockdep_count_forward_deps'
> > Submitter	: Frans Pop <elendil@planet.nl> 
> > Date		: 2008-08-16 19:11 (8 days old)
> > References	: http://marc.info/?l=linux-kernel&m=121891396320127&w=4
> 
> Fixed as per: http://marc.info/?l=linux-kernel&m=121898767530602&w=4
> Adrian mentioned that he'd closed the bug, but apparently not.

The bug is closed now.

Thanks,
Rafael

Re: [Bug #11379] char/tpm: tpm_infineon no longer loaded for HP 2510p laptop

[Rafael J. Wysocki]

On Sunday, 24 of August 2008, Frans Pop wrote:
> On Saturday 23 August 2008, Rafael J. Wysocki wrote:
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11379
> > Subject	: char/tpm: tpm_infineon no longer loaded for HP 2510p laptop
> > Submitter	: Frans Pop <elendil@planet.nl>
> > Date		: 2008-08-18 13:40 (6 days old)
> > References	: http://marc.info/?l=linux-kernel&m=121906698213329&w=4
> > Handled-By	: Bjorn Helgaas <bjorn.helgaas@hp.com>
> 
> Fixed with:
> commit 5e4c6564c95ce127beeefe75e15cd11c93487436
> Author: Kay Sievers <kay.sievers@vrfy.org>
> Date:   Thu Aug 21 15:28:56 2008 +0200
> 
>     pnp: fix "add acpi:* modalias entries"

Thanks,  closed.

Rafael

Re: [Bug #11355] Regression in 2.6.27-rc2 when cross-building the kernel

[Rafael J. Wysocki]

On Saturday, 23 of August 2008, Rafael J. Wysocki wrote:
> This message has been generated automatically as a part of a report
> of recent regressions.
> 
> The following bug entry is on the current list of known regressions
> from 2.6.26.  Please verify if it still should be listed and let me know
> (either way).
> 
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11355
> Subject		: Regression in 2.6.27-rc2 when cross-building the kernel
> Submitter	: Larry Finger <Larry.Finger@lwfinger.net>
> Date		: 2008-08-16 2:38 (8 days old)
> References	: http://marc.info/?l=linux-kernel&m=121885432118368&w=4

As I wrote in the Bugzilla, I'm seeing a related problem.

Namely, I build kernels on one box, with 'make O=<target>', then I mount
<target> on another one over NFS, 'cd' to it and try to install the kernel
modules with 'make modules_install'.  This results in 'HOSTCC firmware/ihex2fw'
and 'fatal error: ...: Read-only file system'.  It's readily reproducible.

Commenting out line 1130 of Makefile
("$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst")
obviously helps, so it looks like Makefile.fwinst needs fixing.

Thanks,
Rafael

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Rafael J. Wysocki]

On Saturday, 23 of August 2008, Rafael J. Wysocki wrote:
[--snip--]

> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11361
> Subject		: my servers with nvidia mcp55 nic don't work with msi in second kernel by kexec
> Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
> Date		: 2008-08-17 6:25 (7 days old)
> References	: http://marc.info/?l=linux-kernel&m=121895439927053&w=4
> Handled-By	: Rafael J. Wysocki <rjw@sisk.pl>
> Patch		: http://marc.info/?l=linux-kernel&m=121917167232014&w=4

[--snip--]
 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11358
> Subject		: net: forcedeth call restore mac addr in nv_shutdown path
> Submitter	: Yinghai Lu <yhlu.kernel@gmail.com>
> Date		: 2008-08-17 3:30 (7 days old)
> References	: http://marc.info/?l=linux-kernel&m=121894389018584&w=4
> Handled-By	: Yinghai Lu <yhlu.kernel@gmail.com>
> Patch		: http://marc.info/?l=linux-kernel&m=121894389018584&w=4

Jeff, do you have the patches for these two in your queue?

Rafael

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Sean Young]

On Sun, Aug 24, 2008 at 11:52:06AM -0700, Linus Torvalds wrote:
> On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
> > 
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11354
> > Subject		: AMD Elan regression with 2.6.27-rc3
> > Submitter	: Sean Young <sean@mess.org>
> > Date		: 2008-08-15 18:37 (9 days old)
> > References	: http://marc.info/?l=linux-kernel&m=121882578430056&w=4
> 
> Peter? Ingo? Alok?
> 
> This _looks_ like it might be due to "x86: merge the TSC cpu-freq code" 
> thing by Alok, where we do this:
> 
> 	+static struct notifier_block time_cpufreq_notifier_block = {
> 	+       .notifier_call  = time_cpufreq_notifier
> 	+};
> 	+
> 	+static int __init cpufreq_tsc(void)
> 	+{
> 	+       cpufreq_register_notifier(&time_cpufreq_notifier_block,
> 	+                               CPUFREQ_TRANSITION_NOTIFIER);
> 	+       return 0;
> 	+}
> 
> but that's just _insane_ if the CPU doesn't even support TSC to begin 
> with. Also, in the actual time_cpufreq_notifier(), we do:
> 
> 	if (cpu_has(&cpu_data(freq->cpu), X86_FEATURE_CONSTANT_TSC))
> 		return 0;
> 
> and this is stupid because:
> 
>  (a) if the CPU has no TSC at all, then it sure as hell won't have a 
>      _constant_ one, so we'll actually continue into the function.
> 
>  (b) and why the hell is this done at run-time in the notifier, and not in 
>      the "cpufreq_tsc" init function? If anybody mixes totally different 
>      kinds of CPU's in SMP, they deserve whatever they want.
> 
> so why is the patch not something like the appended?
> 
> Sean, does this make any difference for you?

Yes, this patch fixes it.

Thanks
Sean

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[H. Peter Anvin]

Linus Torvalds wrote:
>> 
> diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
> index 46af716..9bed5ca 100644
> --- a/arch/x86/kernel/tsc.c
> +++ b/arch/x86/kernel/tsc.c
> @@ -325,6 +325,10 @@ static struct notifier_block time_cpufreq_notifier_block = {
>  
>  static int __init cpufreq_tsc(void)
>  {
> +	if (!cpu_has_tsc)
> +		return 0;
> +	if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
> +		return 0;
>  	cpufreq_register_notifier(&time_cpufreq_notifier_block,
>  				CPUFREQ_TRANSITION_NOTIFIER);
>  	return 0;

I added this patch to x86/urgent.

	-hpa

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Benjamin Herrenschmidt]

> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11414
> Subject		: Random crashes with 2.6.27-rc3 on PPC
> Submitter	: Michael Buesch <mb@bu3sch.de>
> Date		: 2008-08-23 14:10 (1 days old)
> References	: http://marc.info/?l=linux-kernel&m=121950076812616&w=4

This appears to be a gcc bug when -fno-omit-stack-pointer is used (which
we mostly don't need on ppc anyway except that another gcc stupidity makes
it mandatory for -pg which ftrace needs).

We're working on a two fold workaround: removing -fno-omit-stack-pointer
in all the cases where we don't really need it, and for when we do (ie,
CONFIG_FTRACE becaues of -pg), using -mno-sched-epilog which seems to
work around it.

The root cause in gcc hasn't been fully identified yet.

Ben.

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Sun, 24 Aug 2008, David Greaves wrote:
> 
> Given that I'll manage at best 1 bisect/day with a reasonable chance of data
> corruption and hardware intermittency screwing it all up I thought it best to
> ask first in case there was another debug approach that could work.

Well, regardless, I think it would be good to fill in the hardware info, 
especially wrt CPU data and the exact SATA controller you have.

There's another regression for SATA cold/hot boot issues, and while that 
one looks very different, and is probably not really related, it's still a 
good idea to try to see if we can match them up. See

	Bug-Entry       : http://bugzilla.kernel.org/show_bug.cgi?id=11343
	Subject         : SATA Cold Boot Problems with 2.6.27-rc[23] on nVidia 680i
	Submitter       : Manny Maxwell <mannymax@mannymax.net>
	Date            : 2008-08-14 4:16 (10 days old)
	References      : http://marc.info/?l=linux-kernel&m=121868782917600&w=4

which actually has a patch, and which seems to work fine in 2.6.26 (so not 
only is failure pattern different, the point were it starts is different). 

But regardless of the big differences, it does seem to point to some 
weakness in SATA initialization. But is it limited to _that_ particular 
SATA controller, or just a few ones? Or a generic issue? Without more 
reports to really find a pattern, I don't think we have a clue, and the 
two may be _totally_ unrelated in all ways, but it would be good to at 
least report and log the information you have..

Oh, I just noticed that your dmesg _does_ mention sata_sil and sata_via, 
so we know which of two drivers it would be, at least. Not the nVidia one.

However, there's been tons of changes in soem core functions: both the 
reset handling and the wait-for-ready has changed and caused lots of churn 
across most drivers in between 2.6.25 and 2.6.26. 

> PS if anyone really is interested then I am happy to try the bisection once I've
> moved her to a new box; otherwise I'm happy to close this.

I think it would be good to try to bisect. It could be something that is 
really just limited to that particular machine (maybe it really is some 
flaky hardware that just triggers some timing changes), but more likely it 
isn't. So the more information, the better. So keep the thing open as long 
as somebody is willing to try to gather more info, by all means.

		Linus

Re: [Bug #11254] KVM: fix userspace ABI breakage

[Avi Kivity]

Adrian Bunk wrote:
> The discussion in Bugzilla whether it is a regression at all can be 
> condensed to the following question:
>
> Can a struct that is part of the 2.6.26 userspace headers be defined to 
> be part of an "experimental ABI" and therefore be changed?
>   

It is part of the experimental ABI.

However, as I'm going to apply your patch (as being the simplest fix, 
and as there is no measurable performance impact), the question is moot.

-- 
error compiling committee.c: too many arguments to function

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Rafael J. Wysocki]

On Monday, 25 of August 2008, Benjamin Herrenschmidt wrote:
> 
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11414
> > Subject		: Random crashes with 2.6.27-rc3 on PPC
> > Submitter	: Michael Buesch <mb@bu3sch.de>
> > Date		: 2008-08-23 14:10 (1 days old)
> > References	: http://marc.info/?l=linux-kernel&m=121950076812616&w=4
> 
> This appears to be a gcc bug when -fno-omit-stack-pointer is used (which
> we mostly don't need on ppc anyway except that another gcc stupidity makes
> it mandatory for -pg which ftrace needs).
> 
> We're working on a two fold workaround: removing -fno-omit-stack-pointer
> in all the cases where we don't really need it, and for when we do (ie,
> CONFIG_FTRACE becaues of -pg), using -mno-sched-epilog which seems to
> work around it.
> 
> The root cause in gcc hasn't been fully identified yet.

Thanks Ben.

I've already dropped it from the list of recent regressions.

Rafael

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

Linus Torvalds wrote:
> 
> On Sat, 23 Aug 2008, Linus Torvalds wrote:
>> This one makes no sense. It's triggering a BUG_ON(in_interrupt()), but 
>> then the call chain shows that there is no interrupt going on.
> 
> Ahh, later in that thread there's another totally unrelated oops in 
> debug_mutex_add_waiter().
> 
> I'd guess that it is really wild pointer corrupting memory, quite possibly 
> due to a double free or something like that. Alan - it would be good to 
> run with DEBUG_PAGE_ALLOC and SLUB debugging etc if you don't already do 
> that?
> 
> 		Linus
> 

I'll add those in - as to the repeatability: The "bad" kernels seem to
repeat quite reliably - not only in terms of counts (5 or 6 times in a
row before trying something else), but also in terms of the "what" -
either the original issue () or the other kernel with the later issue
(debug_mutex_add_waiter). That's /goodness/ in that it should help
narrow it down.

I'll make sure the kernel is still failing this morning, and then add in
DEBUG_PAGE_ALLOC and if that doesn't help, SLUB debugging...

Alan

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

Arjan van de Ven wrote:

> 
> Wonder what gcc is in use?
> (newer ones tend to be a ton better... but maybe Alex is using a really
> old one)

I'm running Ubuntu 8.04 w/ gcc:

gcc (GCC) 4.2.3 (Ubuntu 4.2.3-2ubuntu7)

Alan

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

[-- Attachment #1: Type: text/plain, Size: 182 bytes --]

Before adding any more debugging, this is the status of my kernel boots:
3 times in a row w/ this same error. (Primary problem is the same,
secondary stacks differ of course.)

Alan

[-- Attachment #2: prob3.txt --]
[-- Type: text/plain, Size: 25900 bytes --]

Loading, please [    6.482953] busybox used greatest stack depth: 4840 bytes left
wait...
[    6.521876] all_generic_ide used greatest stack depth: 4784 bytes left
Begin: Loading essential drivers... ...
[    6.625509] fuse init (API version 7.9)
[    6.625509] modprobe used greatest stack depth: 1720 bytes left
[    6.644854] ACPI: SSDT CFFD0D0A, 08C4 (r1 HPQOEM  CPU_TM2        1 MSFT  100000E)
[    6.651489] BUG: unable to handle kernel NULL pointer dereference at 0000000000000858
[    6.655631] IP: [<ffffffff8025e302>] debug_mutex_add_waiter+0x32/0x80
[    6.655631] PGD 21a0a4067 PUD 21a4bd067 PMD 0
[    6.655631] Oops: 0002 [1] SMP
[    6.655631] CPU 1
[    6.655631] Modules linked in: processor(+) fan thermal_sys fuse
[    6.655631] Pid: 1259, comm: modprobe Not tainted 2.6.27-rc3 #29
[    6.655631] RIP: 0010:[<ffffffff8025e302>]  [<ffffffff8025e302>] debug_mutex_add_waiter+0x32/0x80
[    6.655631] RSP: 0018:ffff88021a4e7998  EFLAGS: 00010002
[    6.655631] RAX: 0000000000000000 RBX: ffff88021a4e79d8 RCX: 0000000000000000
[    6.655631] RDX: 0000000000000001 RSI: ffff88021a4e79d8 RDI: ffffffffa0091a60
[    6.655631] RBP: ffff88021a4e79b8 R08: ffffffff811deff0 R09: ffff8800a6fdb000
[    6.655631] R10: ffffffffa008f524 R11: 0000000000000000 R12: ffffffffa0091a60
[    6.655631] R13: ffff88021a4e6000 R14: ffff88021a9c40a0 R15: ffffffffa0091a98
[    6.655631] FS:  00007f233f11d6e0(0000) GS:ffff88022fc02a00(0000) knlGS:0000000000000000
[    6.655631] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    6.655631] CR2: 0000000000000858 CR3: 000000021a07e000 CR4: 00000000000006e0
[    6.655631] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    6.655631] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[    6.655631] Process modprobe (pid: 1259, threadinfo ffff88021a4e6000, task ffff88021a9c40a0)
[    6.655631] Stack:  0000000000000000 ffffffffa0091a60 0000000000000246 ffffffffa008f524
[    6.655631]  ffff88021a4e7a38 ffffffff8049f596 ffffffffa008f524 ffffffffa0091a18
[    6.655631]  ffff88021a4e79d8 ffff88021a4e79d8 1111111111111111 1111111111111111
[    6.655631] Call Trace:
[    6.655631]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    6.655631]  [<ffffffff8049f596>] mutex_lock_nested+0xa6/0x250
[    6.655631]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    6.655631]  [<ffffffff803635c4>] ? idr_pre_get+0x44/0x90
[    6.655631]  [<ffffffffa008f524>] get_idr+0x44/0xa0 [thermal_sys]
[    6.655631]  [<ffffffffa008fe43>] thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    6.655631]  [<ffffffffa019b2a3>] acpi_processor_start+0x64b/0x774 [processor]
[    6.655631]  [<ffffffff8031a94b>] ? __sysfs_add_one+0x6b/0xa0
[    6.655631]  [<ffffffff8031ba3c>] ? sysfs_do_create_link+0xbc/0x150
[    6.655631]  [<ffffffff803a7f5e>] acpi_start_single_object+0x2d/0x52
[    6.655631]  [<ffffffff803a9556>] acpi_device_probe+0x7e/0x92
[    6.655631]  [<ffffffff803dd3eb>] driver_probe_device+0x9b/0x1a0
[    6.655631]  [<ffffffff803dd576>] __driver_attach+0x86/0x90
[    6.655631]  [<ffffffff803dd4f0>] ? __driver_attach+0x0/0x90
[    6.655631]  [<ffffffff803dc93d>] bus_for_each_dev+0x5d/0x90
[    6.655631]  [<ffffffff803dd22c>] driver_attach+0x1c/0x20
[    6.655631]  [<ffffffff803dcf79>] bus_add_driver+0x1e9/0x260
[    6.655631]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    6.655631]  [<ffffffff803dd74f>] driver_register+0x5f/0x140
[    6.655631]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    6.655631]  [<ffffffff803a9866>] acpi_bus_register_driver+0x3e/0x40
[    6.655631]  [<ffffffffa0222094>] acpi_processor_init+0x94/0x107 [processor]
[    6.655631]  [<ffffffff80209040>] _stext+0x40/0x180
[    6.655631]  [<ffffffff802a8911>] ? __vunmap+0xa1/0x110
[    6.655631]  [<ffffffff802676c2>] sys_init_module+0x142/0x1dc0
[    6.655631]  [<ffffffff80367b16>] ? __up_read+0x46/0xb0
[    6.655631]  [<ffffffff8048e570>] ? cpu_down+0x0/0x70
[    6.655631]  [<ffffffff8020c34b>] system_call_fastpath+0x16/0x1b
[    6.655631]
[    6.655631]
[    6.655631] Code: 20 48 89 5d e8 4c 89 65 f0 48 89 f3 4c 89 6d f8 8b 47 08 49 89 d5 49 89 fc 89 c2 25 ff ff 00 00 c1 ea 10 39 c2 74 1d 49 8b 4
[    6.655631] RIP  [<ffffffff8025e302>] debug_mutex_add_waiter+0x32/0x80
[    6.655631]  RSP <ffff88021a4e7998>
[    6.655631] CR2: 0000000000000858
[    6.655631] ---[ end trace 8bbd31df1403e48e ]---
[    7.024992] modprobe used greatest stack depth: 408 bytes left
[    7.030988] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[    7.031053] IP: [<ffffffff8023f39c>] do_exit+0x28c/0xa10
[    7.031053] PGD 0
[    7.031053] Oops: 0000 [2] SMP
[    7.031053] CPU 1
[    7.031053] Modules linked in: processor(+) fan thermal_sys fuse
[    7.031053] Pid: 1259, comm: modprobe Tainted: G      D   2.6.27-rc3 #29
[    7.031053] RIP: 0010:[<ffffffff8023f39c>]  [<ffffffff8023f39c>] do_exit+0x28c/0xa10
[    7.031053] RSP: 0018:ffff88021a4e77e8  EFLAGS: 00010246
[    7.031053] RAX: 0000000000000000 RBX: 0000000000000198 RCX: 0000000000000000
[    7.031053] RDX: 0000000000000000 RSI: ffffffff802740d0 RDI: 0000000000000000
[    7.031053] RBP: ffff88021a4e7848 R08: 0000000000000001 R09: 0000000000000000
[    7.031053] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88021a9c40a0
[    7.031053] R13: 0000000000000009 R14: ffff88021a4e78e8 R15: ffff88021a18b8a0
[    7.031053] FS:  0000000000000000(0000) GS:ffff88022fc02a00(0000) knlGS:0000000000000000
[    7.031053] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    7.031053] CR2: 0000000000000048 CR3: 0000000000201000 CR4: 00000000000006e0
[    7.031053] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    7.031053] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[    7.031053] Process modprobe (pid: 1259, threadinfo ffff88021a4e6000, task ffff88021a9c40a0)
[    7.031053] Stack:  0000000000000001 0000000000000001 0000000000000040 0000000000000001
[    7.031053]  ffff88021a4e7828 ffffffff803c7d59 0000000000000092 0000000000000092
[    7.031053]  ffff88021a4e78e8 0000000000000009 ffff88021a4e78e8 ffff88021a18b8a0
[    7.031053] Call Trace:
[    7.031053]  [<ffffffff803c7d59>] ? do_unblank_screen+0x19/0x130
[    7.031053]  [<ffffffff804a1a57>] oops_end+0x87/0x90
[    7.031053]  [<ffffffff804a3d13>] do_page_fault+0x663/0x800
[    7.031053]  [<ffffffff804a162d>] error_exit+0x0/0x9a
[    7.031053]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.031053]  [<ffffffff8025e302>] ? debug_mutex_add_waiter+0x32/0x80
[    7.031053]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.031053]  [<ffffffff8049f596>] mutex_lock_nested+0xa6/0x250
[    7.031053]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.031053]  [<ffffffff803635c4>] ? idr_pre_get+0x44/0x90
[    7.031053]  [<ffffffffa008f524>] get_idr+0x44/0xa0 [thermal_sys]
[    7.031053]  [<ffffffffa008fe43>] thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    7.031053]  [<ffffffffa019b2a3>] acpi_processor_start+0x64b/0x774 [processor]
[    7.031053]  [<ffffffff8031a94b>] ? __sysfs_add_one+0x6b/0xa0
[    7.031053]  [<ffffffff8031ba3c>] ? sysfs_do_create_link+0xbc/0x150
[    7.031053]  [<ffffffff803a7f5e>] acpi_start_single_object+0x2d/0x52
[    7.031053]  [<ffffffff803a9556>] acpi_device_probe+0x7e/0x92
[    7.031053]  [<ffffffff803dd3eb>] driver_probe_device+0x9b/0x1a0
[    7.031053]  [<ffffffff803dd576>] __driver_attach+0x86/0x90
[    7.031053]  [<ffffffff803dd4f0>] ? __driver_attach+0x0/0x90
[    7.031053]  [<ffffffff803dc93d>] bus_for_each_dev+0x5d/0x90
[    7.031053]  [<ffffffff803dd22c>] driver_attach+0x1c/0x20
[    7.031053]  [<ffffffff803dcf79>] bus_add_driver+0x1e9/0x260
[    7.031053]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.031053]  [<ffffffff803dd74f>] driver_register+0x5f/0x140
[    7.031053]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.031053]  [<ffffffff803a9866>] acpi_bus_register_driver+0x3e/0x40
[    7.031053]  [<ffffffffa0222094>] acpi_processor_init+0x94/0x107 [processor]
[    7.031053]  [<ffffffff80209040>] _stext+0x40/0x180
[    7.031053]  [<ffffffff802a8911>] ? __vunmap+0xa1/0x110
[    7.031053]  [<ffffffff802676c2>] sys_init_module+0x142/0x1dc0
[    7.031053]  [<ffffffff80367b16>] ? __up_read+0x46/0xb0
[    7.031053]  [<ffffffff8048e570>] ? cpu_down+0x0/0x70
[    7.031053]  [<ffffffff8020c34b>] system_call_fastpath+0x16/0x1b
[    7.031053]
[    7.031053]
[    7.031053] Code: e8 8a e3 0e 00 8b 45 b8 85 c0 74 16 49 8b 84 24 40 07 00 00 8b 80 4c 01 00 00 85 c0 0f 85 77 07 00 00 49 8b 44 24 08 48 8b 4
[    7.031053] RIP  [<ffffffff8023f39c>] do_exit+0x28c/0xa10
[    7.031053]  RSP <ffff88021a4e77e8>
[    7.031053] CR2: 0000000000000048
[    7.421063] ------------[ cut here ]------------
[    7.424883] WARNING: at kernel/sched_fair.c:884 hrtick_start_fair+0x187/0x190()
[    7.424883] Modules linked in: processor(+) fan thermal_sys fuse
[    7.424883] Pid: 1259, comm: modprobe Tainted: G      D   2.6.27-rc3 #29
[    7.424883]
[    7.424883] Call Trace:
[    7.424883]  <IRQ>  [<ffffffff8023baef>] warn_on_slowpath+0x5f/0x80
[    7.424883]  [<ffffffff8022d927>] hrtick_start_fair+0x187/0x190
[    7.424883]  [<ffffffff8022ec79>] enqueue_task_fair+0x49/0x250
[    7.424883]  [<ffffffff8022c290>] enqueue_task+0x50/0x60
[    7.424883]  [<ffffffff8022c2c3>] activate_task+0x23/0x40
[    7.424883]  [<ffffffff80231653>] try_to_wake_up+0x253/0x280
[    7.424883]  [<ffffffff8023168d>] default_wake_function+0xd/0x10
[    7.424883]  [<ffffffff802521d1>] autoremove_wake_function+0x11/0x40
[    7.424883]  [<ffffffff8022bd6a>] __wake_up_common+0x5a/0x90
[    7.424883]  [<ffffffff8022d373>] __wake_up+0x43/0x70
[    7.424883]  [<ffffffff8024e910>] ? delayed_work_timer_fn+0x0/0x40
[    7.424883]  [<ffffffff8024df68>] insert_work+0x48/0x50
[    7.424883]  [<ffffffff8024e8f1>] __queue_work+0x31/0x50
[    7.424883]  [<ffffffff8024e942>] delayed_work_timer_fn+0x32/0x40
[    7.424883]  [<ffffffff80245e5b>] run_timer_softirq+0x1bb/0x230
[    7.424883]  [<ffffffff80255afa>] ? ktime_get_ts+0x4a/0x60
[    7.424883]  [<ffffffff8024157a>] __do_softirq+0x7a/0xf0
[    7.424883]  [<ffffffff8025cd8e>] ? tick_program_event+0x3e/0x70
[    7.424883]  [<ffffffff8020d69c>] call_softirq+0x1c/0x30
[    7.424883]  [<ffffffff8020f28d>] do_softirq+0x3d/0x80
[    7.424883]  [<ffffffff802414f5>] irq_exit+0x85/0x90
[    7.424883]  [<ffffffff8021d648>] smp_apic_timer_interrupt+0x88/0xc0
[    7.424883]  [<ffffffff8020d0e6>] apic_timer_interrupt+0x66/0x70
[    7.424883]  <EOI>  [<ffffffff804a1a1a>] ? oops_end+0x4a/0x90
[    7.424883]  [<ffffffff804a3d13>] ? do_page_fault+0x663/0x800
[    7.424883]  [<ffffffff804a162d>] ? error_exit+0x0/0x9a
[    7.424883]  [<ffffffff802740d0>] ? release_css_set_taskexit+0x0/0x10
[    7.424883]  [<ffffffff8023f39c>] ? do_exit+0x28c/0xa10
[    7.424883]  [<ffffffff8023f376>] ? do_exit+0x266/0xa10
[    7.424883]  [<ffffffff803c7d59>] ? do_unblank_screen+0x19/0x130
[    7.424883]  [<ffffffff804a1a57>] ? oops_end+0x87/0x90
[    7.424883]  [<ffffffff804a3d13>] ? do_page_fault+0x663/0x800
[    7.424883]  [<ffffffff804a162d>] ? error_exit+0x0/0x9a
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff8025e302>] ? debug_mutex_add_waiter+0x32/0x80
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff8049f596>] ? mutex_lock_nested+0xa6/0x250
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff803635c4>] ? idr_pre_get+0x44/0x90
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffffa008fe43>] ? thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    7.424883]  [<ffffffffa019b2a3>] ? acpi_processor_start+0x64b/0x774 [processor]
[    7.424883]  [<ffffffff8031a94b>] ? __sysfs_add_one+0x6b/0xa0
[    7.424883]  [<ffffffff8031ba3c>] ? sysfs_do_create_link+0xbc/0x150
[    7.424883]  [<ffffffff803a7f5e>] ? acpi_start_single_object+0x2d/0x52
[    7.424883]  [<ffffffff803a9556>] ? acpi_device_probe+0x7e/0x92
[    7.424883]  [<ffffffff803dd3eb>] ? driver_probe_device+0x9b/0x1a0
[    7.424883]  [<ffffffff803dd576>] ? __driver_attach+0x86/0x90
[    7.424883]  [<ffffffff803dd4f0>] ? __driver_attach+0x0/0x90
[    7.424883]  [<ffffffff803dc93d>] ? bus_for_each_dev+0x5d/0x90
[    7.424883]  [<ffffffff803dd22c>] ? driver_attach+0x1c/0x20
[    7.424883]  [<ffffffff803dcf79>] ? bus_add_driver+0x1e9/0x260
[    7.424883]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.424883]  [<ffffffff803dd74f>] ? driver_register+0x5f/0x140
[    7.424883]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.424883]  [<ffffffff803a9866>] ? acpi_bus_register_driver+0x3e/0x40
[    7.424883]  [<ffffffffa0222094>] ? acpi_processor_init+0x94/0x107 [processor]
[    7.424883]  [<ffffffff80209040>] ? _stext+0x40/0x180
[    7.424883]  [<ffffffff802a8911>] ? __vunmap+0xa1/0x110
[    7.424883]  [<ffffffff802676c2>] ? sys_init_module+0x142/0x1dc0
[    7.424883]  [<ffffffff80367b16>] ? __up_read+0x46/0xb0
[    7.424883]  [<ffffffff8048e570>] ? cpu_down+0x0/0x70
[    7.424883]  [<ffffffff8020c34b>] ? system_call_fastpath+0x16/0x1b
[    7.424883]
[    7.424883] ---[ end trace 8bbd31df1403e48e ]---
[    7.424883] ------------[ cut here ]------------
[    7.424883] kernel BUG at kernel/sched.c:1155!
[    7.424883] invalid opcode: 0000 [3] SMP
[    7.424883] CPU 1
[    7.424883] Modules linked in: processor(+) fan thermal_sys fuse
[    7.424883] Pid: 1259, comm: modprobe Tainted: G      D W 2.6.27-rc3 #29
[    7.424883] RIP: 0010:[<ffffffff8022cc2b>]  [<ffffffff8022cc2b>] resched_task+0x6b/0x70
[    7.424883] RSP: 0018:ffff88022f0abce0  EFLAGS: 00010046
[    7.424883] RAX: 0000000000000709 RBX: 0000000004bfe971 RCX: ffff88021a4e6000
[    7.424883] RDX: 0000000000000709 RSI: 0000000000000000 RDI: ffff88021a9c40a0
[    7.424883] RBP: ffff88022f0abce0 R08: ffff88022f180038 R09: ffff88021a9c40d8
[    7.424883] R10: ffffffff810c9e00 R11: 0000000000000000 R12: ffff8800a6fc9000
[    7.424883] R13: ffffffff810c9e00 R14: ffff88021a9c40a0 R15: 0000000000000001
[    7.424883] FS:  0000000000000000(0000) GS:ffff88022fc02a00(0000) knlGS:0000000000000000
[    7.424883] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    7.424883] CR2: 0000000000000048 CR3: 0000000000201000 CR4: 00000000000006e0
[    7.424883] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    7.424883] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[    7.424883] Process modprobe (pid: 1259, threadinfo ffff88021a4e6000, task ffff88021a9c40a0)
[    7.424883] Stack:  ffff88022f0abd20 ffffffff802387b3 0000000000000400 0000000000400000
[    7.424883]  ffff88022f180000 ffff8800280a4e00 0000000000000001 0000000000000003
[    7.424883]  ffff88022f0abd70 ffffffff802314bf 0000000100000001 0000000000000000
[    7.424883] Call Trace:
[    7.424883]  <IRQ>  [<ffffffff802387b3>] check_preempt_wakeup+0x133/0x1c0
[    7.424883]  [<ffffffff802314bf>] try_to_wake_up+0xbf/0x280
[    7.424883]  [<ffffffff8023168d>] default_wake_function+0xd/0x10
[    7.424883]  [<ffffffff802521d1>] autoremove_wake_function+0x11/0x40
[    7.424883]  [<ffffffff8022bd6a>] __wake_up_common+0x5a/0x90
[    7.424883]  [<ffffffff8022d373>] __wake_up+0x43/0x70
[    7.424883]  [<ffffffff8024e910>] ? delayed_work_timer_fn+0x0/0x40
[    7.424883]  [<ffffffff8024df68>] insert_work+0x48/0x50
[    7.424883]  [<ffffffff8024e8f1>] __queue_work+0x31/0x50
[    7.424883]  [<ffffffff8024e942>] delayed_work_timer_fn+0x32/0x40
[    7.424883]  [<ffffffff80245e5b>] run_timer_softirq+0x1bb/0x230
[    7.424883]  [<ffffffff80255afa>] ? ktime_get_ts+0x4a/0x60
[    7.424883]  [<ffffffff8024157a>] __do_softirq+0x7a/0xf0
[    7.424883]  [<ffffffff8025cd8e>] ? tick_program_event+0x3e/0x70
[    7.424883]  [<ffffffff8020d69c>] call_softirq+0x1c/0x30
[    7.424883]  [<ffffffff8020f28d>] do_softirq+0x3d/0x80
[    7.424883]  [<ffffffff802414f5>] irq_exit+0x85/0x90
[    7.424883]  [<ffffffff8021d648>] smp_apic_timer_interrupt+0x88/0xc0
[    7.424883]  [<ffffffff8020d0e6>] apic_timer_interrupt+0x66/0x70
[    7.424883]  <EOI>  [<ffffffff804a1a1a>] ? oops_end+0x4a/0x90
[    7.424883]  [<ffffffff804a3d13>] ? do_page_fault+0x663/0x800
[    7.424883]  [<ffffffff804a162d>] ? error_exit+0x0/0x9a
[    7.424883]  [<ffffffff802740d0>] ? release_css_set_taskexit+0x0/0x10
[    7.424883]  [<ffffffff8023f39c>] ? do_exit+0x28c/0xa10
[    7.424883]  [<ffffffff8023f376>] ? do_exit+0x266/0xa10
[    7.424883]  [<ffffffff803c7d59>] ? do_unblank_screen+0x19/0x130
[    7.424883]  [<ffffffff804a1a57>] ? oops_end+0x87/0x90
[    7.424883]  [<ffffffff804a3d13>] ? do_page_fault+0x663/0x800
[    7.424883]  [<ffffffff804a162d>] ? error_exit+0x0/0x9a
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff8025e302>] ? debug_mutex_add_waiter+0x32/0x80
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff8049f596>] ? mutex_lock_nested+0xa6/0x250
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff803635c4>] ? idr_pre_get+0x44/0x90
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffffa008fe43>] ? thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    7.424883]  [<ffffffffa019b2a3>] ? acpi_processor_start+0x64b/0x774 [processor]
[    7.424883]  [<ffffffff8031a94b>] ? __sysfs_add_one+0x6b/0xa0
[    7.424883]  [<ffffffff8031ba3c>] ? sysfs_do_create_link+0xbc/0x150
[    7.424883]  [<ffffffff803a7f5e>] ? acpi_start_single_object+0x2d/0x52
[    7.424883]  [<ffffffff803a9556>] ? acpi_device_probe+0x7e/0x92
[    7.424883]  [<ffffffff803dd3eb>] ? driver_probe_device+0x9b/0x1a0
[    7.424883]  [<ffffffff803dd576>] ? __driver_attach+0x86/0x90
[    7.424883]  [<ffffffff803dd4f0>] ? __driver_attach+0x0/0x90
[    7.424883]  [<ffffffff803dc93d>] ? bus_for_each_dev+0x5d/0x90
[    7.424883]  [<ffffffff803dd22c>] ? driver_attach+0x1c/0x20
[    7.424883]  [<ffffffff803dcf79>] ? bus_add_driver+0x1e9/0x260
[    7.424883]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.424883]  [<ffffffff803dd74f>] ? driver_register+0x5f/0x140
[    7.424883]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.424883]  [<ffffffff803a9866>] ? acpi_bus_register_driver+0x3e/0x40
[    7.424883]  [<ffffffffa0222094>] ? acpi_processor_init+0x94/0x107 [processor]
[    7.424883]  [<ffffffff80209040>] ? _stext+0x40/0x180
[    7.424883]  [<ffffffff802a8911>] ? __vunmap+0xa1/0x110
[    7.424883]  [<ffffffff802676c2>] ? sys_init_module+0x142/0x1dc0
[    7.424883]  [<ffffffff80367b16>] ? __up_read+0x46/0xb0
[    7.424883]  [<ffffffff8048e570>] ? cpu_down+0x0/0x70
[    7.424883]  [<ffffffff8020c34b>] ? system_call_fastpath+0x16/0x1b
[    7.424883]
[    7.424883]
[    7.424883] Code: 8b 47 08 8b 50 1c 65 8b 04 25 24 00 00 00 39 c2 74 0d 0f ae f0 48 8b 47 08 f6 40 18 04 74 02 c9 c3 89 d7 ff 15 1f 7b 3c 00 c
[    7.424883] RIP  [<ffffffff8022cc2b>] resched_task+0x6b/0x70
[    7.424883]  RSP <ffff88022f0abce0>
[    7.424883] ---[ end trace 8bbd31df1403e48e ]---
[    7.424883] Kernel panic - not syncing: Aiee, killing interrupt handler!
[    7.424883] ------------[ cut here ]------------
[    7.424883] WARNING: at kernel/smp.c:328 smp_call_function_mask+0x25a/0x260()
[    7.424883] Modules linked in: processor(+) fan thermal_sys fuse
[    7.424883] Pid: 1259, comm: modprobe Tainted: G      D W 2.6.27-rc3 #29
[    7.424883]
[    7.424883] Call Trace:
[    7.424883]  <IRQ>  [<ffffffff8023baef>] warn_on_slowpath+0x5f/0x80
[    7.424883]  [<ffffffff8026514a>] smp_call_function_mask+0x25a/0x260
[    7.424883]  [<ffffffff803695bd>] ? string+0x3d/0xd0
[    7.424883]  [<ffffffff80369a8b>] ? vsnprintf+0x43b/0x720
[    7.424883]  [<ffffffff803695bd>] ? string+0x3d/0xd0
[    7.424883]  [<ffffffff80369a8b>] ? vsnprintf+0x43b/0x720
[    7.424883]  [<ffffffff803695bd>] ? string+0x3d/0xd0
[    7.424883]  [<ffffffff803695bd>] ? string+0x3d/0xd0
[    7.424883]  [<ffffffff80369a8b>] ? vsnprintf+0x43b/0x720
[    7.424883]  [<ffffffff80368d5e>] ? number+0x2ae/0x2d0
[    7.424883]  [<ffffffff80368d5e>] ? number+0x2ae/0x2d0
[    7.424883]  [<ffffffff80269ecd>] ? kallsyms_lookup+0x5d/0xa0
[    7.424883]  [<ffffffff80368d5e>] ? number+0x2ae/0x2d0
[    7.424883]  [<ffffffff80369a8b>] ? vsnprintf+0x43b/0x720
[    7.424883]  [<ffffffff80369dd8>] ? sprintf+0x68/0x70
[    7.424883]  [<ffffffff803695bd>] ? string+0x3d/0xd0
[    7.424883]  [<ffffffff804a3fa3>] ? __atomic_notifier_call_chain+0x83/0xa0
[    7.424883]  [<ffffffff804a3f20>] ? __atomic_notifier_call_chain+0x0/0xa0
[    7.424883]  [<ffffffff804a0ef6>] ? _spin_unlock+0x26/0x30
[    7.424883]  [<ffffffff8021c470>] ? stop_this_cpu+0x0/0x30
[    7.424883]  [<ffffffff80265190>] smp_call_function+0x40/0x50
[    7.424883]  [<ffffffff8021c4f3>] native_smp_send_stop+0x23/0x40
[    7.424883]  [<ffffffff8023be3f>] panic+0xaf/0x190
[    7.424883]  [<ffffffff8023cc97>] ? printk+0x67/0x70
[    7.424883]  [<ffffffff8049f4e9>] ? mutex_unlock+0x9/0x10
[    7.424883]  [<ffffffff80256d11>] ? blocking_notifier_call_chain+0x11/0x20
[    7.424883]  [<ffffffff8023f979>] do_exit+0x869/0xa10
[    7.424883]  [<ffffffff803c7d59>] ? do_unblank_screen+0x19/0x130
[    7.424883]  [<ffffffff804a1a57>] oops_end+0x87/0x90
[    7.424883]  [<ffffffff8020e08e>] die+0x5e/0x90
[    7.424883]  [<ffffffff804a1f60>] do_trap+0x130/0x150
[    7.424883]  [<ffffffff8020e662>] do_invalid_op+0x92/0xb0
[    7.424883]  [<ffffffff8022cc2b>] ? resched_task+0x6b/0x70
[    7.424883]  [<ffffffff804a162d>] error_exit+0x0/0x9a
[    7.424883]  [<ffffffff8022cc2b>] ? resched_task+0x6b/0x70
[    7.424883]  [<ffffffff802387b3>] check_preempt_wakeup+0x133/0x1c0
[    7.424883]  [<ffffffff802314bf>] try_to_wake_up+0xbf/0x280
[    7.424883]  [<ffffffff8023168d>] default_wake_function+0xd/0x10
[    7.424883]  [<ffffffff802521d1>] autoremove_wake_function+0x11/0x40
[    7.424883]  [<ffffffff8022bd6a>] __wake_up_common+0x5a/0x90
[    7.424883]  [<ffffffff8022d373>] __wake_up+0x43/0x70
[    7.424883]  [<ffffffff8024e910>] ? delayed_work_timer_fn+0x0/0x40
[    7.424883]  [<ffffffff8024df68>] insert_work+0x48/0x50
[    7.424883]  [<ffffffff8024e8f1>] __queue_work+0x31/0x50
[    7.424883]  [<ffffffff8024e942>] delayed_work_timer_fn+0x32/0x40
[    7.424883]  [<ffffffff80245e5b>] run_timer_softirq+0x1bb/0x230
[    7.424883]  [<ffffffff80255afa>] ? ktime_get_ts+0x4a/0x60
[    7.424883]  [<ffffffff8024157a>] __do_softirq+0x7a/0xf0
[    7.424883]  [<ffffffff8025cd8e>] ? tick_program_event+0x3e/0x70
[    7.424883]  [<ffffffff8020d69c>] call_softirq+0x1c/0x30
[    7.424883]  [<ffffffff8020f28d>] do_softirq+0x3d/0x80
[    7.424883]  [<ffffffff802414f5>] irq_exit+0x85/0x90
[    7.424883]  [<ffffffff8021d648>] smp_apic_timer_interrupt+0x88/0xc0
[    7.424883]  [<ffffffff8020d0e6>] apic_timer_interrupt+0x66/0x70
[    7.424883]  <EOI>  [<ffffffff804a1a1a>] ? oops_end+0x4a/0x90
[    7.424883]  [<ffffffff804a3d13>] ? do_page_fault+0x663/0x800
[    7.424883]  [<ffffffff804a162d>] ? error_exit+0x0/0x9a
[    7.424883]  [<ffffffff802740d0>] ? release_css_set_taskexit+0x0/0x10
[    7.424883]  [<ffffffff8023f39c>] ? do_exit+0x28c/0xa10
[    7.424883]  [<ffffffff8023f376>] ? do_exit+0x266/0xa10
[    7.424883]  [<ffffffff803c7d59>] ? do_unblank_screen+0x19/0x130
[    7.424883]  [<ffffffff804a1a57>] ? oops_end+0x87/0x90
[    7.424883]  [<ffffffff804a3d13>] ? do_page_fault+0x663/0x800
[    7.424883]  [<ffffffff804a162d>] ? error_exit+0x0/0x9a
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff8025e302>] ? debug_mutex_add_waiter+0x32/0x80
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff8049f596>] ? mutex_lock_nested+0xa6/0x250
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffff803635c4>] ? idr_pre_get+0x44/0x90
[    7.424883]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.424883]  [<ffffffffa008fe43>] ? thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    7.424883]  [<ffffffffa019b2a3>] ? acpi_processor_start+0x64b/0x774 [processor]
[    7.424883]  [<ffffffff8031a94b>] ? __sysfs_add_one+0x6b/0xa0
[    7.424883]  [<ffffffff8031ba3c>] ? sysfs_do_create_link+0xbc/0x150
[    7.424883]  [<ffffffff803a7f5e>] ? acpi_start_single_object+0x2d/0x52
[    7.424883]  [<ffffffff803a9556>] ? acpi_device_probe+0x7e/0x92
[    7.424883]  [<ffffffff803dd3eb>] ? driver_probe_device+0x9b/0x1a0
[    7.424883]  [<ffffffff803dd576>] ? __driver_attach+0x86/0x90
[    7.424883]  [<ffffffff803dd4f0>] ? __driver_attach+0x0/0x90
[    7.424883]  [<ffffffff803dc93d>] ? bus_for_each_dev+0x5d/0x90
[    7.424883]  [<ffffffff803dd22c>] ? driver_attach+0x1c/0x20
[    7.424883]  [<ffffffff803dcf79>] ? bus_add_driver+0x1e9/0x260
[    7.424883]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.424883]  [<ffffffff803dd74f>] ? driver_register+0x5f/0x140
[    7.424883]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.424883]  [<ffffffff803a9866>] ? acpi_bus_register_driver+0x3e/0x40
[    7.424883]  [<ffffffffa0222094>] ? acpi_processor_init+0x94/0x107 [processor]
[    7.424883]  [<ffffffff80209040>] ? _stext+0x40/0x180
[    7.424883]  [<ffffffff802a8911>] ? __vunmap+0xa1/0x110
[    7.424883]  [<ffffffff802676c2>] ? sys_init_module+0x142/0x1dc0
[    7.424883]  [<ffffffff80367b16>] ? __up_read+0x46/0xb0
[    7.424883]  [<ffffffff8048e570>] ? cpu_down+0x0/0x70
[    7.424883]  [<ffffffff8020c34b>] ? system_call_fastpath+0x16/0x1b
[    7.424883]
[    7.424883] ---[ end trace 8bbd31df1403e48e ]---

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

[-- Attachment #1: Type: text/plain, Size: 803 bytes --]

Linus Torvalds wrote:
> 
> On Sat, 23 Aug 2008, Linus Torvalds wrote:
>> This one makes no sense. It's triggering a BUG_ON(in_interrupt()), but 
>> then the call chain shows that there is no interrupt going on.
> 
> Ahh, later in that thread there's another totally unrelated oops in 
> debug_mutex_add_waiter().
> 
> I'd guess that it is really wild pointer corrupting memory, quite possibly 
> due to a double free or something like that. Alan - it would be good to 
> run with DEBUG_PAGE_ALLOC and SLUB debugging etc if you don't already do 
> that?

With /just/ DEBUG_PAGE_ALLOC defined, I have seen two general panic types:

o  A new double fault w/ SMP_DEBUG_PAGEALLOC problem (prob4.txt)

o  The NULL pointer dereference @ 0x858 (prob4a.txt)

Enabling SLUB debugging to see what that shows

Alan

[-- Attachment #2: prob4.txt --]
[-- Type: text/plain, Size: 4170 bytes --]

Begin: Loading essential drivers... ...
[    6.680626] fuse init (API version 7.9)
[    6.680626] modprobe used greatest stack depth: 1720 bytes left
[    6.704224] double fault: 0000 [1] SMP DEBUG_PAGEALLOC
[    6.704224] CPU 1
[    6.704224] Modules linked in: processor(+) fan thermal_sys fuse
[    6.710629] Pid: 1259, comm: modprobe Not tainted 2.6.27-rc3 #30
[    6.710629] RIP: 0010:[<ffffffff802214dc>]  [<ffffffff802214dc>] flat_send_IPI_allbutself+0x2c/0x80
[    6.710629] RSP: 0018:ffff88021a513ff8  EFLAGS: 00010282
[    6.710629] RAX: ffffffff805f5520 RBX: ffff88021a5141f8 RCX: 000000000000003f
[    6.710629] RDX: 0000000000000200 RSI: ffffffff80bf7920 RDI: ffff88021a5141f8
[    6.710629] RBP: ffff88021a514408 R08: 0000000000000040 R09: 0000000000000040
[    6.710629] R10: 0000000000001000 R11: 0000000000000000 R12: 00000000000000fc
[    6.710629] R13: ffff88021a514eb8 R14: 0000000000000001 R15: ffffffff8021cba0
[    6.710629] FS:  00007f39acc136e0(0000) GS:ffff88022fc81a00(0000) knlGS:0000000000000000
[    6.710629] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    6.710629] CR2: ffff88021a513fe8 CR3: 000000021a469000 CR4: 00000000000006e0
[    6.710629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    6.710629] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[    6.710629] Process modprobe (pid: 1259, threadinfo ffff88021a514000, task ffff88021a9da050)
[    6.710629] Stack: <1>BUG: unable to handle kernel paging request at ffff88021a513ff8
[    6.710629] IP: [<ffffffff8020dd22>] show_stack_log_lvl+0x82/0x130
[    6.710629] PGD 202063 PUD 10067 PMD 22f176163 PTE 800000021a513160
[    6.710629] Oops: 0000 [2] SMP DEBUG_PAGEALLOC
[    6.710629] CPU 1
[    6.710629] Modules linked in: processor(+) fan thermal_sys fuse
[    6.710629] Pid: 1259, comm: modprobe Not tainted 2.6.27-rc3 #30
[    6.710629] RIP: 0010:[<ffffffff8020dd22>]  [<ffffffff8020dd22>] show_stack_log_lvl+0x82/0x130
[    6.710629] RSP: 0018:ffff88022f12ce28  EFLAGS: 00010046
[    6.710629] RAX: ffff88022fc81a00 RBX: ffff88021a513ff8 RCX: 000000000000000c
[    6.710629] RDX: ffff88021a513ff8 RSI: ffff88022f12cf58 RDI: 0000000000000000
[    6.710629] RBP: ffff88022f12ce78 R08: ffffffff8059aea9 R09: 0000000000000001
[    6.710629] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[    6.710629] R13: ffff88022f127fc0 R14: ffff88022f12bfc0 R15: 0000000000000000
[    6.710629] FS:  00007f39acc136e0(0000) GS:ffff88022fc81a00(0000) knlGS:0000000000000000
[    6.710629] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    6.710629] CR2: ffff88021a513ff8 CR3: 000000021a469000 CR4: 00000000000006e0
[    6.710629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    6.710629] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[    6.710629] Process modprobe (pid: 1259, threadinfo ffff88021a514000, task ffff88021a9da050)
[    6.710629] Stack:  ffff88022f12ce78 ffffffff8059aea9 ffff88021a514408 ffff88022f12cf58
[    6.710629]  ffff88021a513ff8 ffff88021a9da050 0000000000000000 ffff88022f12cf58
[    6.710629]  0000000000000040 000000000000002b ffff88022f12ceb8 ffffffff8020dea8
[    6.710629] Call Trace:
[    6.710629]  <#DF>  [<ffffffff8020dea8>] show_registers+0xd8/0x260
[    6.710629]  [<ffffffff8021cba0>] ? do_flush_tlb_all+0x0/0x40
[    6.710629]  [<ffffffff804a2083>] __die+0xa3/0x120
[    6.710629]  [<ffffffff8020e073>] die+0x43/0x90
[    6.710629]  [<ffffffff8020e1e3>] do_double_fault+0x63/0x70
[    6.710629]  [<ffffffff8020d4fd>] double_fault+0x7d/0x90
[    6.710629]  [<ffffffff8021cba0>] ? do_flush_tlb_all+0x0/0x40
[    6.710629]  [<ffffffff802214dc>] ? flat_send_IPI_allbutself+0x2c/0x80
[    6.710629]  <<EOE>>
[    6.710629]
[    6.710629] Code: 55 d0 85 c9 48 89 d3 7e 5a 45 31 e4 eb 44 4c 39 f3 77 44 66 0f 1f 44 00 00 74 7e 45 85 e4 74 0b 41 f6 c4 03 0f 1f 44 00 00 7
[    6.720629] RIP  [<ffffffff8020dd22>] show_stack_log_lvl+0x82/0x130
[    6.720629]  RSP <ffff88022f12ce28>
[    6.720629] CR2: ffff88021a513ff8
[    6.720629] ---[ end trace d4fdf12ff3e07cc3 ]---
[    7.052961] modprobe used greatest stack depth: 920 bytes left
Killed

[-- Attachment #3: prob4a.txt --]
[-- Type: text/plain, Size: 21642 bytes --]

[    6.551876] all_generic_ide used greatest stack depth: 4784 bytes left
Begin: Loading essential drivers... ...
[    6.658003] fuse init (API version 7.9)
[    6.661876] modprobe used greatest stack depth: 1720 bytes left
[    6.683510] ACPI: SSDT CFFD0D0A, 08C4 (r1 HPQOEM  CPU_TM2        1 MSFT  100000E)
[    6.690632] BUG: unable to handle kernel NULL pointer dereference at 0000000000000858
[    6.690632] IP: [<ffffffff8025e512>] debug_mutex_add_waiter+0x32/0x80
[    6.690632] PGD 21a145067 PUD 22f13a067 PMD 0
[    6.690632] Oops: 0002 [1] SMP DEBUG_PAGEALLOC
[    6.690632] CPU 1
[    6.690632] Modules linked in: processor(+) fan thermal_sys fuse
[    6.690632] Pid: 1259, comm: modprobe Not tainted 2.6.27-rc3 #30
[    6.690632] RIP: 0010:[<ffffffff8025e512>]  [<ffffffff8025e512>] debug_mutex_add_waiter+0x32/0x80
[    6.690632] RSP: 0018:ffff88021a959998  EFLAGS: 00010002
[    6.690632] RAX: 0000000000000000 RBX: ffff88021a9599d8 RCX: 0000000000000000
[    6.690632] RDX: 0000000000000001 RSI: ffff88021a9599d8 RDI: ffffffffa0091a60
[    6.690632] RBP: ffff88021a9599b8 R08: ffffffff811deff0 R09: ffff8800a6fdb000
[    6.690632] R10: ffffffffa008f524 R11: 0000000000000000 R12: ffffffffa0091a60
[    6.690632] R13: ffff88021a958000 R14: ffff88021a1c2050 R15: ffffffffa0091a98
[    6.690632] FS:  00007f28063c16e0(0000) GS:ffff88022fc81a00(0000) knlGS:0000000000000000
[    6.690632] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    6.690632] CR2: 0000000000000858 CR3: 0000000219c64000 CR4: 00000000000006e0
[    6.690632] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    6.690632] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[    6.690632] Process modprobe (pid: 1259, threadinfo ffff88021a958000, task ffff88021a1c2050)
[    6.690632] Stack:  0000000000000000 ffffffffa0091a60 0000000000000246 ffffffffa008f524
[    6.690632]  ffff88021a959a38 ffffffff8049f856 ffffffffa008f524 ffffffffa0091a18
[    6.690632]  ffff88021a9599d8 ffff88021a9599d8 1111111111111111 1111111111111111
[    6.690632] Call Trace:
[    6.690632]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    6.690632]  [<ffffffff8049f856>] mutex_lock_nested+0xa6/0x250
[    6.690632]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    6.690632]  [<ffffffff80363884>] ? idr_pre_get+0x44/0x90
[    6.690632]  [<ffffffffa008f524>] get_idr+0x44/0xa0 [thermal_sys]
[    6.690632]  [<ffffffffa008fe43>] thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    6.690632]  [<ffffffffa019b2a3>] acpi_processor_start+0x64b/0x774 [processor]
[    6.690632]  [<ffffffff8031ac0b>] ? __sysfs_add_one+0x6b/0xa0
[    6.690632]  [<ffffffff8031bcfc>] ? sysfs_do_create_link+0xbc/0x150
[    6.690632]  [<ffffffff803a821e>] acpi_start_single_object+0x2d/0x52
[    6.690632]  [<ffffffff803a9816>] acpi_device_probe+0x7e/0x92
[    6.690632]  [<ffffffff803dd6ab>] driver_probe_device+0x9b/0x1a0
[    6.690632]  [<ffffffff803dd836>] __driver_attach+0x86/0x90
[    6.690632]  [<ffffffff803dd7b0>] ? __driver_attach+0x0/0x90
[    6.690632]  [<ffffffff803dcbfd>] bus_for_each_dev+0x5d/0x90
[    6.690632]  [<ffffffff803dd4ec>] driver_attach+0x1c/0x20
[    6.690632]  [<ffffffff803dd239>] bus_add_driver+0x1e9/0x260
[    6.690632]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    6.690632]  [<ffffffff803dda0f>] driver_register+0x5f/0x140
[    6.690632]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    6.690632]  [<ffffffff803a9b26>] acpi_bus_register_driver+0x3e/0x40
[    6.690632]  [<ffffffffa0222094>] acpi_processor_init+0x94/0x107 [processor]
[    6.690632]  [<ffffffff80209040>] _stext+0x40/0x180
[    6.690632]  [<ffffffff802a8bd1>] ? __vunmap+0xa1/0x110
[    6.690632]  [<ffffffff802678d2>] sys_init_module+0x142/0x1dc0
[    6.690632]  [<ffffffff80367dd6>] ? __up_read+0x46/0xb0
[    6.690632]  [<ffffffff8048e830>] ? cpu_down+0x0/0x70
[    6.690632]  [<ffffffff8020c34b>] system_call_fastpath+0x16/0x1b
[    6.690632]
[    6.690632]
[    6.690632] Code: 20 48 89 5d e8 4c 89 65 f0 48 89 f3 4c 89 6d f8 8b 47 08 49 89 d5 49 89 fc 89 c2 25 ff ff 00 00 c1 ea 10 39 c2 74 1d 49 8b 4
[    6.690632] RIP  [<ffffffff8025e512>] debug_mutex_add_waiter+0x32/0x80
[    6.690632]  RSP <ffff88021a959998>
[    6.690632] CR2: 0000000000000858
[    6.690632] ---[ end trace 62c38812ae35bad0 ]---
[    7.060556] ------------[ cut here ]------------
[    7.060741] WARNING: at kernel/sched_fair.c:884 hrtick_start_fair+0x187/0x190()
[    7.060741] Modules linked in: processor(+) fan thermal_sys fuse
[    7.060741] Pid: 1259, comm: modprobe Tainted: G      D   2.6.27-rc3 #30
[    7.060741]
[    7.060741] Call Trace:
[    7.060741]  <IRQ>  [<ffffffff8023bcff>] warn_on_slowpath+0x5f/0x80
[    7.060741]  [<ffffffff8022db37>] hrtick_start_fair+0x187/0x190
[    7.060741]  [<ffffffff8022ee89>] enqueue_task_fair+0x49/0x250
[    7.060741]  [<ffffffff8022c4a0>] enqueue_task+0x50/0x60
[    7.060741]  [<ffffffff8022c4d3>] activate_task+0x23/0x40
[    7.060741]  [<ffffffff80231863>] try_to_wake_up+0x253/0x280
[    7.060741]  [<ffffffff8023189d>] default_wake_function+0xd/0x10
[    7.060741]  [<ffffffff802523e1>] autoremove_wake_function+0x11/0x40
[    7.060741]  [<ffffffff8022bf7a>] __wake_up_common+0x5a/0x90
[    7.060741]  [<ffffffff8022d583>] __wake_up+0x43/0x70
[    7.060741]  [<ffffffff8024eb20>] ? delayed_work_timer_fn+0x0/0x40
[    7.060741]  [<ffffffff8024e178>] insert_work+0x48/0x50
[    7.060741]  [<ffffffff8024eb01>] __queue_work+0x31/0x50
[    7.060741]  [<ffffffff8024eb52>] delayed_work_timer_fn+0x32/0x40
[    7.060741]  [<ffffffff8024606b>] run_timer_softirq+0x1bb/0x230
[    7.060741]  [<ffffffff80255d0a>] ? ktime_get_ts+0x4a/0x60
[    7.060741]  [<ffffffff8024178a>] __do_softirq+0x7a/0xf0
[    7.060741]  [<ffffffff8025cf9e>] ? tick_program_event+0x3e/0x70
[    7.060741]  [<ffffffff8020d69c>] call_softirq+0x1c/0x30
[    7.060741]  [<ffffffff8020f28d>] do_softirq+0x3d/0x80
[    7.060741]  [<ffffffff80241705>] irq_exit+0x85/0x90
[    7.060741]  [<ffffffff8021d648>] smp_apic_timer_interrupt+0x88/0xc0
[    7.060741]  [<ffffffff8020d0e6>] apic_timer_interrupt+0x66/0x70
[    7.060741]  <EOI>  [<ffffffff804a15eb>] ? _spin_unlock_irq+0x2b/0x30
[    7.060741]  [<ffffffff804a0e75>] ? __down_read+0xa5/0xb7
[    7.060741]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060741]  [<ffffffff8049fe57>] ? down_read+0x37/0x40
[    7.060741]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060741]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060741]  [<ffffffff8023f4ad>] ? do_exit+0x18d/0xa10
[    7.060741]  [<ffffffff803c8019>] ? do_unblank_screen+0x19/0x130
[    7.060741]  [<ffffffff804a1d17>] ? oops_end+0x87/0x90
[    7.060741]  [<ffffffff804a3fe3>] ? do_page_fault+0x663/0x800
[    7.060741]  [<ffffffff804a18ed>] ? error_exit+0x0/0x9a
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffff8025e512>] ? debug_mutex_add_waiter+0x32/0x80
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffff8049f856>] ? mutex_lock_nested+0xa6/0x250
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffff80363884>] ? idr_pre_get+0x44/0x90
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffffa008fe43>] ? thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    7.060741]  [<ffffffffa019b2a3>] ? acpi_processor_start+0x64b/0x774 [processor]
[    7.060741]  [<ffffffff8031ac0b>] ? __sysfs_add_one+0x6b/0xa0
[    7.060741]  [<ffffffff8031bcfc>] ? sysfs_do_create_link+0xbc/0x150
[    7.060741]  [<ffffffff803a821e>] ? acpi_start_single_object+0x2d/0x52
[    7.060741]  [<ffffffff803a9816>] ? acpi_device_probe+0x7e/0x92
[    7.060741]  [<ffffffff803dd6ab>] ? driver_probe_device+0x9b/0x1a0
[    7.060741]  [<ffffffff803dd836>] ? __driver_attach+0x86/0x90
[    7.060741]  [<ffffffff803dd7b0>] ? __driver_attach+0x0/0x90
[    7.060741]  [<ffffffff803dcbfd>] ? bus_for_each_dev+0x5d/0x90
[    7.060741]  [<ffffffff803dd4ec>] ? driver_attach+0x1c/0x20
[    7.060741]  [<ffffffff803dd239>] ? bus_add_driver+0x1e9/0x260
[    7.060741]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.060741]  [<ffffffff803dda0f>] ? driver_register+0x5f/0x140
[    7.060741]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.060741]  [<ffffffff803a9b26>] ? acpi_bus_register_driver+0x3e/0x40
[    7.060741]  [<ffffffffa0222094>] ? acpi_processor_init+0x94/0x107 [processor]
[    7.060741]  [<ffffffff80209040>] ? _stext+0x40/0x180
[    7.060741]  [<ffffffff802a8bd1>] ? __vunmap+0xa1/0x110
[    7.060741]  [<ffffffff802678d2>] ? sys_init_module+0x142/0x1dc0
[    7.060741]  [<ffffffff80367dd6>] ? __up_read+0x46/0xb0
[    7.060741]  [<ffffffff8048e830>] ? cpu_down+0x0/0x70
[    7.060741]  [<ffffffff8020c34b>] ? system_call_fastpath+0x16/0x1b
[    7.060741]
[    7.060741] ---[ end trace 62c38812ae35bad0 ]---
[    7.060741] ------------[ cut here ]------------
[    7.060741] kernel BUG at kernel/sched.c:1155!
[    7.060741] invalid opcode: 0000 [2] SMP DEBUG_PAGEALLOC
[    7.060741] CPU 1
[    7.060741] Modules linked in: processor(+) fan thermal_sys fuse
[    7.060741] Pid: 1259, comm: modprobe Tainted: G      D W 2.6.27-rc3 #30
[    7.060741] RIP: 0010:[<ffffffff8022ce3b>]  [<ffffffff8022ce3b>] resched_task+0x6b/0x70
[    7.060741] RSP: 0018:ffff88022f12bce0  EFLAGS: 00010046
[    7.060741] RAX: 00000000000006e5 RBX: 00000000012c627a RCX: ffff88021a958000
[    7.060741] RDX: 00000000000006e5 RSI: 0000000000000000 RDI: ffff88021a1c2050
[    7.060741] RBP: ffff88022f12bce0 R08: ffff88022f1d8038 R09: ffff88021a1c2088
[    7.060741] R10: ffffffff810c9e00 R11: 0000000000000000 R12: ffff8800a6fc9000
[    7.060741] R13: ffffffff810c9e00 R14: ffff88021a1c2050 R15: 0000000000000001
[    7.060741] FS:  00007f28063c16e0(0000) GS:ffff88022fc81a00(0000) knlGS:0000000000000000
[    7.060741] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[    7.060741] CR2: 0000000000000858 CR3: 0000000219c64000 CR4: 00000000000006e0
[    7.060741] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    7.060741] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[    7.060741] Process modprobe (pid: 1259, threadinfo ffff88021a958000, task ffff88021a1c2050)
[    7.060741] Stack:  ffff88022f12bd20 ffffffff802389c3 0000000000000400 0000000000400000
[    7.060741]  ffff88022f1d8000 ffff8800280a4e00 0000000000000001 0000000000000003
[    7.060741]  ffff88022f12bd70 ffffffff802316cf 0000000100000001 0000000000000000
[    7.060741] Call Trace:
[    7.060741]  <IRQ>  [<ffffffff802389c3>] check_preempt_wakeup+0x133/0x1c0
[    7.060741]  [<ffffffff802316cf>] try_to_wake_up+0xbf/0x280
[    7.060741]  [<ffffffff8023189d>] default_wake_function+0xd/0x10
[    7.060741]  [<ffffffff802523e1>] autoremove_wake_function+0x11/0x40
[    7.060741]  [<ffffffff8022bf7a>] __wake_up_common+0x5a/0x90
[    7.060741]  [<ffffffff8022d583>] __wake_up+0x43/0x70
[    7.060741]  [<ffffffff8024eb20>] ? delayed_work_timer_fn+0x0/0x40
[    7.060741]  [<ffffffff8024e178>] insert_work+0x48/0x50
[    7.060741]  [<ffffffff8024eb01>] __queue_work+0x31/0x50
[    7.060741]  [<ffffffff8024eb52>] delayed_work_timer_fn+0x32/0x40
[    7.060741]  [<ffffffff8024606b>] run_timer_softirq+0x1bb/0x230
[    7.060741]  [<ffffffff80255d0a>] ? ktime_get_ts+0x4a/0x60
[    7.060741]  [<ffffffff8024178a>] __do_softirq+0x7a/0xf0
[    7.060741]  [<ffffffff8025cf9e>] ? tick_program_event+0x3e/0x70
[    7.060741]  [<ffffffff8020d69c>] call_softirq+0x1c/0x30
[    7.060741]  [<ffffffff8020f28d>] do_softirq+0x3d/0x80
[    7.060741]  [<ffffffff80241705>] irq_exit+0x85/0x90
[    7.060741]  [<ffffffff8021d648>] smp_apic_timer_interrupt+0x88/0xc0
[    7.060741]  [<ffffffff8020d0e6>] apic_timer_interrupt+0x66/0x70
[    7.060741]  <EOI>  [<ffffffff804a15eb>] ? _spin_unlock_irq+0x2b/0x30
[    7.060741]  [<ffffffff804a0e75>] ? __down_read+0xa5/0xb7
[    7.060741]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060741]  [<ffffffff8049fe57>] ? down_read+0x37/0x40
[    7.060741]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060741]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060741]  [<ffffffff8023f4ad>] ? do_exit+0x18d/0xa10
[    7.060741]  [<ffffffff803c8019>] ? do_unblank_screen+0x19/0x130
[    7.060741]  [<ffffffff804a1d17>] ? oops_end+0x87/0x90
[    7.060741]  [<ffffffff804a3fe3>] ? do_page_fault+0x663/0x800
[    7.060741]  [<ffffffff804a18ed>] ? error_exit+0x0/0x9a
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffff8025e512>] ? debug_mutex_add_waiter+0x32/0x80
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffff8049f856>] ? mutex_lock_nested+0xa6/0x250
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffff80363884>] ? idr_pre_get+0x44/0x90
[    7.060741]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060741]  [<ffffffffa008fe43>] ? thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    7.060741]  [<ffffffffa019b2a3>] ? acpi_processor_start+0x64b/0x774 [processor]
[    7.060741]  [<ffffffff8031ac0b>] ? __sysfs_add_one+0x6b/0xa0
[    7.060741]  [<ffffffff8031bcfc>] ? sysfs_do_create_link+0xbc/0x150
[    7.060741]  [<ffffffff803a821e>] ? acpi_start_single_object+0x2d/0x52
[    7.060741]  [<ffffffff803a9816>] ? acpi_device_probe+0x7e/0x92
[    7.060741]  [<ffffffff803dd6ab>] ? driver_probe_device+0x9b/0x1a0
[    7.060741]  [<ffffffff803dd836>] ? __driver_attach+0x86/0x90
[    7.060741]  [<ffffffff803dd7b0>] ? __driver_attach+0x0/0x90
[    7.060741]  [<ffffffff803dcbfd>] ? bus_for_each_dev+0x5d/0x90
[    7.060741]  [<ffffffff803dd4ec>] ? driver_attach+0x1c/0x20
[    7.060741]  [<ffffffff803dd239>] ? bus_add_driver+0x1e9/0x260
[    7.060741]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.060741]  [<ffffffff803dda0f>] ? driver_register+0x5f/0x140
[    7.060741]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.060741]  [<ffffffff803a9b26>] ? acpi_bus_register_driver+0x3e/0x40
[    7.060741]  [<ffffffffa0222094>] ? acpi_processor_init+0x94/0x107 [processor]
[    7.060741]  [<ffffffff80209040>] ? _stext+0x40/0x180
[    7.060741]  [<ffffffff802a8bd1>] ? __vunmap+0xa1/0x110
[    7.060741]  [<ffffffff802678d2>] ? sys_init_module+0x142/0x1dc0
[    7.060741]  [<ffffffff80367dd6>] ? __up_read+0x46/0xb0
[    7.060741]  [<ffffffff8048e830>] ? cpu_down+0x0/0x70
[    7.060741]  [<ffffffff8020c34b>] ? system_call_fastpath+0x16/0x1b
[    7.060741]
[    7.060741]
[    7.060741] Code: 8b 47 08 8b 50 1c 65 8b 04 25 24 00 00 00 39 c2 74 0d 0f ae f0 48 8b 47 08 f6 40 18 04 74 02 c9 c3 89 d7 ff 15 0f 79 3c 00 c
[    7.060741] RIP  [<ffffffff8022ce3b>] resched_task+0x6b/0x70
[    7.060741]  RSP <ffff88022f12bce0>
[    7.060741] ---[ end trace 62c38812ae35bad0 ]---
[    7.060741] Kernel panic - not syncing: Aiee, killing interrupt handler!
[    7.060741] ------------[ cut here ]------------
[    7.060741] WARNING: at kernel/smp.c:328 smp_call_function_mask+0x25a/0x260()
[    7.060741] Modules linked in: processor(+) fan thermal_sys fuse
[    7.060741] Pid: 1259, comm: modprobe Tainted: G      D W 2.6.27-rc3 #30
[    7.060741]
[    7.060741] Call Trace:
[    7.060741]  <IRQ>  [<ffffffff8023bcff>] warn_on_slowpath+0x5f/0x80
[    7.060741]  [<ffffffff8026535a>] smp_call_function_mask+0x25a/0x260
[    7.060741]  [<ffffffff8036987d>] ? string+0x3d/0xd0
[    7.060741]  [<ffffffff80369d4b>] ? vsnprintf+0x43b/0x720
[    7.060741]  [<ffffffff8036987d>] ? string+0x3d/0xd0
[    7.060741]  [<ffffffff80369d4b>] ? vsnprintf+0x43b/0x720
[    7.060741]  [<ffffffff8036987d>] ? string+0x3d/0xd0
[    7.060741]  [<ffffffff8036987d>] ? string+0x3d/0xd0
[    7.060741]  [<ffffffff80369d4b>] ? vsnprintf+0x43b/0x720
[    7.060741]  [<ffffffff8036901e>] ? number+0x2ae/0x2d0
[    7.060741]  [<ffffffff8036901e>] ? number+0x2ae/0x2d0
[    7.060741]  [<ffffffff8026a0dd>] ? kallsyms_lookup+0x5d/0xa0
[    7.060741]  [<ffffffff8036901e>] ? number+0x2ae/0x2d0
[    7.060741]  [<ffffffff80369d4b>] ? vsnprintf+0x43b/0x720
[    7.060741]  [<ffffffff8036a098>] ? sprintf+0x68/0x70
[    7.060741]  [<ffffffff8036987d>] ? string+0x3d/0xd0
[    7.060741]  [<ffffffff804a4273>] ? __atomic_notifier_call_chain+0x83/0xa0
[    7.060741]  [<ffffffff804a41f0>] ? __atomic_notifier_call_chain+0x0/0xa0
[    7.060741]  [<ffffffff804a11b6>] ? _spin_unlock+0x26/0x30
[    7.060741]  [<ffffffff8021c470>] ? stop_this_cpu+0x0/0x30
[    7.060741]  [<ffffffff802653a0>] smp_call_function+0x40/0x50
[    7.060741]  [<ffffffff8021c4f3>] native_smp_send_stop+0x23/0x40
[    7.060741]  [<ffffffff8023c04f>] panic+0xaf/0x190
[    7.060741]  [<ffffffff8023cea7>] ? printk+0x67/0x70
[    7.060741]  [<ffffffff8049f7a9>] ? mutex_unlock+0x9/0x10
[    7.060741]  [<ffffffff80256f21>] ? blocking_notifier_call_chain+0x11/0x20
[    7.060741]  [<ffffffff8023fb89>] do_exit+0x869/0xa10
[    7.060741]  [<ffffffff803c8019>] ? do_unblank_screen+0x19/0x130
[    7.060741]  [<ffffffff804a1d17>] oops_end+0x87/0x90
[    7.060741]  [<ffffffff8020e08e>] die+0x5e/0x90
[    7.060741]  [<ffffffff804a2230>] do_trap+0x130/0x150
[    7.060741]  [<ffffffff8020e662>] do_invalid_op+0x92/0xb0
[    7.060741]  [<ffffffff8022ce3b>] ? resched_task+0x6b/0x70
[    7.060741]  [<ffffffff804a18ed>] error_exit+0x0/0x9a
[    7.060741]  [<ffffffff8022ce3b>] ? resched_task+0x6b/0x70
[    7.060741]  [<ffffffff802389c3>] check_preempt_wakeup+0x133/0x1c0
[    7.060741]  [<ffffffff802316cf>] try_to_wake_up+0xbf/0x280
[    7.060741]  [<ffffffff8023189d>] default_wake_function+0xd/0x10
[    7.060741]  [<ffffffff802523e1>] autoremove_wake_function+0x11/0x40
[    7.060741]  [<ffffffff8022bf7a>] __wake_up_common+0x5a/0x90
[    7.060741]  [<ffffffff8022d583>] __wake_up+0x43/0x70
[    7.060741]  [<ffffffff8024eb20>] ? delayed_work_timer_fn+0x0/0x40
[    7.060741]  [<ffffffff8024e178>] insert_work+0x48/0x50
[    7.060741]  [<ffffffff8024eb01>] __queue_work+0x31/0x50
[    7.060741]  [<ffffffff8024eb52>] delayed_work_timer_fn+0x32/0x40
[    7.060741]  [<ffffffff8024606b>] run_timer_softirq+0x1bb/0x230
[    7.060741]  [<ffffffff80255d0a>] ? ktime_get_ts+0x4a/0x60
[    7.060741]  [<ffffffff8024178a>] __do_softirq+0x7a/0xf0
[    7.060741]  [<ffffffff8025cf9e>] ? tick_program_event+0x3e/0x70
[    7.060741]  [<ffffffff8020d69c>] call_softirq+0x1c/0x30
[    7.060741]  [<ffffffff8020f28d>] do_softirq+0x3d/0x80
[    7.060741]  [<ffffffff80241705>] irq_exit+0x85/0x90
[    7.060741]  [<ffffffff8021d648>] smp_apic_timer_interrupt+0x88/0xc0
[    7.060741]  [<ffffffff8020d0e6>] apic_timer_interrupt+0x66/0x70
[    7.060741]  <EOI>  [<ffffffff804a15eb>] ? _spin_unlock_irq+0x2b/0x30
[    7.060741]  [<ffffffff804a0e75>] ? __down_read+0xa5/0xb7
[    7.060741]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060742]  [<ffffffff8049fe57>] ? down_read+0x37/0x40
[    7.060742]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060742]  [<ffffffff8026fdf5>] ? acct_collect+0x45/0x1d0
[    7.060742]  [<ffffffff8023f4ad>] ? do_exit+0x18d/0xa10
[    7.060742]  [<ffffffff803c8019>] ? do_unblank_screen+0x19/0x130
[    7.060742]  [<ffffffff804a1d17>] ? oops_end+0x87/0x90
[    7.060742]  [<ffffffff804a3fe3>] ? do_page_fault+0x663/0x800
[    7.060742]  [<ffffffff804a18ed>] ? error_exit+0x0/0x9a
[    7.060742]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060742]  [<ffffffff8025e512>] ? debug_mutex_add_waiter+0x32/0x80
[    7.060742]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060742]  [<ffffffff8049f856>] ? mutex_lock_nested+0xa6/0x250
[    7.060742]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060742]  [<ffffffff80363884>] ? idr_pre_get+0x44/0x90
[    7.060742]  [<ffffffffa008f524>] ? get_idr+0x44/0xa0 [thermal_sys]
[    7.060742]  [<ffffffffa008fe43>] ? thermal_cooling_device_register+0x83/0x250 [thermal_sys]
[    7.060742]  [<ffffffffa019b2a3>] ? acpi_processor_start+0x64b/0x774 [processor]
[    7.060742]  [<ffffffff8031ac0b>] ? __sysfs_add_one+0x6b/0xa0
[    7.060742]  [<ffffffff8031bcfc>] ? sysfs_do_create_link+0xbc/0x150
[    7.060742]  [<ffffffff803a821e>] ? acpi_start_single_object+0x2d/0x52
[    7.060742]  [<ffffffff803a9816>] ? acpi_device_probe+0x7e/0x92
[    7.060742]  [<ffffffff803dd6ab>] ? driver_probe_device+0x9b/0x1a0
[    7.060742]  [<ffffffff803dd836>] ? __driver_attach+0x86/0x90
[    7.060742]  [<ffffffff803dd7b0>] ? __driver_attach+0x0/0x90
[    7.060742]  [<ffffffff803dcbfd>] ? bus_for_each_dev+0x5d/0x90
[    7.060742]  [<ffffffff803dd4ec>] ? driver_attach+0x1c/0x20
[    7.060742]  [<ffffffff803dd239>] ? bus_add_driver+0x1e9/0x260
[    7.060742]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.060742]  [<ffffffff803dda0f>] ? driver_register+0x5f/0x140
[    7.060742]  [<ffffffffa0222000>] ? acpi_processor_init+0x0/0x107 [processor]
[    7.060742]  [<ffffffff803a9b26>] ? acpi_bus_register_driver+0x3e/0x40
[    7.060742]  [<ffffffffa0222094>] ? acpi_processor_init+0x94/0x107 [processor]
[    7.060742]  [<ffffffff80209040>] ? _stext+0x40/0x180
[    7.060742]  [<ffffffff802a8bd1>] ? __vunmap+0xa1/0x110
[    7.060742]  [<ffffffff802678d2>] ? sys_init_module+0x142/0x1dc0
[    7.060742]  [<ffffffff80367dd6>] ? __up_read+0x46/0xb0
[    7.060742]  [<ffffffff8048e830>] ? cpu_down+0x0/0x70
[    7.060742]  [<ffffffff8020c34b>] ? system_call_fastpath+0x16/0x1b
[    7.060742]
[    7.060742] ---[ end trace 62c38812ae35bad0 ]---

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Daniel J Blueman]

Hi Linus, Vegard,

On Sun, Aug 24, 2008 at 7:58 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Sun, 24 Aug 2008, Vegard Nossum wrote:
[snip]
> Anyway, I think your patch is likely fine, I just thought it looked a bit
> odd to have a loop to move a list from one head pointer to another.
>
> But regardless, it would need some testing. Daniel?

This opens another lockdep report at boot-time [1] - promoting
pool_lock may not be the best fix?

We then see a new deadlock condition (on the pool_lock spinlock) [2],
which seemingly was avoided by taking the debug-bucket lock first.

We reproduce this by booting with debug_objects=1 and causing a lot of activity.

Daniel

--- [1]

[ INFO: possible irq lock inversion dependency detected ]
2.6.27-rc4-225c-debug #3
---------------------------------------------------------
rcu_sched_grace/9 just changed the state of lock:
 (pool_lock){-...}, at: [<ffffffff80466c2c>] free_object+0x7c/0xc0
but this lock was taken by another, hard-irq-safe lock in the past:
 (xtime_lock){++..}

and interrupts could create inverse lock ordering between them.


other info that might help us debug this:
no locks held by rcu_sched_grace/9.

the first lock's dependencies:
-> (pool_lock){-...} ops: 59 {
   initial-use  at:
                                       [<ffffffff8026f795>]
__lock_acquire+0x1a5/0x1160
                                       [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                       [<ffffffff806a2bb1>] _spin_lock+0x41/0x80
                                       [<ffffffff804675fa>]
__debug_object_init+0x14a/0x3e0
                                       [<ffffffff804678df>]
debug_object_init+0x1f/0x30
                                       [<ffffffff80260eee>]
hrtimer_init+0x2e/0x50
                                       [<ffffffff80237571>]
init_rt_bandwidth+0x41/0x60
                                       [<ffffffff812f3810>]
sched_init+0x72/0x63d
                                       [<ffffffff812e17e2>]
start_kernel+0x19c/0x456
                                       [<ffffffff812e10a9>]
x86_64_start_reservations+0x99/0xb6
                                       [<ffffffff812e11d0>]
x86_64_start_kernel+0xe2/0xe9
                                       [<ffffffffffffffff>] 0xffffffffffffffff
   hardirq-on-W at:
                                       [<ffffffff8026fae9>]
__lock_acquire+0x4f9/0x1160
                                       [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                       [<ffffffff806a2bb1>] _spin_lock+0x41/0x80
                                       [<ffffffff80466c2c>]
free_object+0x7c/0xc0
                                       [<ffffffff8046707e>]
debug_object_free+0xbe/0x130
                                       [<ffffffff806a070e>]
schedule_timeout+0x7e/0xe0
                                       [<ffffffff806a07ce>]
schedule_timeout_interruptible+0x1e/0x20
                                       [<ffffffff8029cfb2>]
rcu_sched_grace_period+0xa2/0x3a0
                                       [<ffffffff8025d50e>] kthread+0x4e/0x90
                                       [<ffffffff8020d919>] child_rip+0xa/0x11
                                       [<ffffffffffffffff>] 0xffffffffffffffff
 }
 ... key      at: [<ffffffff8088f5d8>] pool_lock+0x18/0x40

the second lock's dependencies:
-> (xtime_lock){++..} ops: 211 {
   initial-use  at:
                                       [<ffffffff8026f795>]
__lock_acquire+0x1a5/0x1160
                                       [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                       [<ffffffff806a2bb1>] _spin_lock+0x41/0x80
                                       [<ffffffff812f5628>]
timekeeping_init+0x2f/0x144
                                       [<ffffffff812e189d>]
start_kernel+0x257/0x456
                                       [<ffffffff812e10a9>]
x86_64_start_reservations+0x99/0xb6
                                       [<ffffffff812e11d0>]
x86_64_start_kernel+0xe2/0xe9
                                       [<ffffffffffffffff>] 0xffffffffffffffff
   in-hardirq-W at:
                                       [<ffffffffffffffff>] 0xffffffffffffffff
   in-softirq-W at:
                                       [<ffffffffffffffff>] 0xffffffffffffffff
 }
 ... key      at: [<ffffffff80907220>] xtime_lock+0x20/0x40
 -> (&obj_hash[i].lock){.+..} ops: 1003901 {
    initial-use  at:
                                         [<ffffffff8026f795>]
__lock_acquire+0x1a5/0x1160
                                         [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                         [<ffffffff806a2d43>]
_spin_lock_irqsave+0x53/0x90
                                         [<ffffffff80467567>]
__debug_object_init+0xb7/0x3e0
                                         [<ffffffff804678df>]
debug_object_init+0x1f/0x30
                                         [<ffffffff80260eee>]
hrtimer_init+0x2e/0x50
                                         [<ffffffff80237571>]
init_rt_bandwidth+0x41/0x60
                                         [<ffffffff812f3810>]
sched_init+0x72/0x63d
                                         [<ffffffff812e17e2>]
start_kernel+0x19c/0x456
                                         [<ffffffff812e10a9>]
x86_64_start_reservations+0x99/0xb6
                                         [<ffffffff812e11d0>]
x86_64_start_kernel+0xe2/0xe9
                                         [<ffffffffffffffff>] 0xffffffffffffffff
    in-softirq-W at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
  }
  ... key      at: [<ffffffff81cd2eb0>] __key.16550+0x0/0x8
  -> (pool_lock){-...} ops: 59 {
     initial-use  at:
                                           [<ffffffff8026f795>]
__lock_acquire+0x1a5/0x1160
                                           [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                           [<ffffffff806a2bb1>]
_spin_lock+0x41/0x80
                                           [<ffffffff804675fa>]
__debug_object_init+0x14a/0x3e0
                                           [<ffffffff804678df>]
debug_object_init+0x1f/0x30
                                           [<ffffffff80260eee>]
hrtimer_init+0x2e/0x50
                                           [<ffffffff80237571>]
init_rt_bandwidth+0x41/0x60
                                           [<ffffffff812f3810>]
sched_init+0x72/0x63d
                                           [<ffffffff812e17e2>]
start_kernel+0x19c/0x456
                                           [<ffffffff812e10a9>]
x86_64_start_reservations+0x99/0xb6
                                           [<ffffffff812e11d0>]
x86_64_start_kernel+0xe2/0xe9
                                           [<ffffffffffffffff>]
0xffffffffffffffff
     hardirq-on-W at:
                                           [<ffffffff8026fae9>]
__lock_acquire+0x4f9/0x1160
                                           [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                           [<ffffffff806a2bb1>]
_spin_lock+0x41/0x80
                                           [<ffffffff80466c2c>]
free_object+0x7c/0xc0
                                           [<ffffffff8046707e>]
debug_object_free+0xbe/0x130
                                           [<ffffffff806a070e>]
schedule_timeout+0x7e/0xe0
                                           [<ffffffff806a07ce>]
schedule_timeout_interruptible+0x1e/0x20
                                           [<ffffffff8029cfb2>]
rcu_sched_grace_period+0xa2/0x3a0
                                           [<ffffffff8025d50e>]
kthread+0x4e/0x90
                                           [<ffffffff8020d919>]
child_rip+0xa/0x11
                                           [<ffffffffffffffff>]
0xffffffffffffffff
   }
   ... key      at: [<ffffffff8088f5d8>] pool_lock+0x18/0x40
  ... acquired at:
   [<ffffffff802703b1>] __lock_acquire+0xdc1/0x1160
   [<ffffffff802707e1>] lock_acquire+0x91/0xc0
   [<ffffffff806a2bb1>] _spin_lock+0x41/0x80
   [<ffffffff804675fa>] __debug_object_init+0x14a/0x3e0
   [<ffffffff804678df>] debug_object_init+0x1f/0x30
   [<ffffffff80260eee>] hrtimer_init+0x2e/0x50
   [<ffffffff80237571>] init_rt_bandwidth+0x41/0x60
   [<ffffffff812f3810>] sched_init+0x72/0x63d
   [<ffffffff812e17e2>] start_kernel+0x19c/0x456
   [<ffffffff812e10a9>] x86_64_start_reservations+0x99/0xb6
   [<ffffffff812e11d0>] x86_64_start_kernel+0xe2/0xe9
   [<ffffffffffffffff>] 0xffffffffffffffff

 ... acquired at:
   [<ffffffff802703b1>] __lock_acquire+0xdc1/0x1160
   [<ffffffff802707e1>] lock_acquire+0x91/0xc0
   [<ffffffff806a2d43>] _spin_lock_irqsave+0x53/0x90
   [<ffffffff80467567>] __debug_object_init+0xb7/0x3e0
   [<ffffffff804678df>] debug_object_init+0x1f/0x30
   [<ffffffff80260eee>] hrtimer_init+0x2e/0x50
   [<ffffffff812f577b>] ntp_init+0x1e/0x2b
   [<ffffffff812f5633>] timekeeping_init+0x3a/0x144
   [<ffffffff812e189d>] start_kernel+0x257/0x456
   [<ffffffff812e10a9>] x86_64_start_reservations+0x99/0xb6
   [<ffffffff812e11d0>] x86_64_start_kernel+0xe2/0xe9
   [<ffffffffffffffff>] 0xffffffffffffffff

 -> (clocksource_lock){++..} ops: 214 {
    initial-use  at:
                                         [<ffffffff8026f795>]
__lock_acquire+0x1a5/0x1160
                                         [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                         [<ffffffff806a2d43>]
_spin_lock_irqsave+0x53/0x90
                                         [<ffffffff80266245>]
clocksource_get_next+0x15/0x60
                                         [<ffffffff812f5638>]
timekeeping_init+0x3f/0x144
                                         [<ffffffff812e189d>]
start_kernel+0x257/0x456
                                         [<ffffffff812e10a9>]
x86_64_start_reservations+0x99/0xb6
                                         [<ffffffff812e11d0>]
x86_64_start_kernel+0xe2/0xe9
                                         [<ffffffffffffffff>] 0xffffffffffffffff
    in-hardirq-W at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
    in-softirq-W at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
  }
  ... key      at: [<ffffffff80877bb8>] clocksource_lock+0x18/0x40
 ... acquired at:
   [<ffffffff802703b1>] __lock_acquire+0xdc1/0x1160
   [<ffffffff802707e1>] lock_acquire+0x91/0xc0
   [<ffffffff806a2d43>] _spin_lock_irqsave+0x53/0x90
   [<ffffffff80266245>] clocksource_get_next+0x15/0x60
   [<ffffffff812f5638>] timekeeping_init+0x3f/0x144
   [<ffffffff812e189d>] start_kernel+0x257/0x456
   [<ffffffff812e10a9>] x86_64_start_reservations+0x99/0xb6
   [<ffffffff812e11d0>] x86_64_start_kernel+0xe2/0xe9
   [<ffffffffffffffff>] 0xffffffffffffffff

 -> (old_style_seqlock_init){++..} ops: 210 {
    initial-use  at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
    in-hardirq-W at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
    in-softirq-W at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
  }
  ... key      at: [<ffffffff812d61a0>] nl80211_policy+0xda0/0x2c00
 ... acquired at:
   [<ffffffffffffffff>] 0xffffffffffffffff

 -> (ftrace_shutdown_lock){++..} ops: 480 {
    initial-use  at:
                                         [<ffffffff8026f795>]
__lock_acquire+0x1a5/0x1160
                                         [<ffffffff802707e1>]
lock_acquire+0x91/0xc0
                                         [<ffffffff806a2d43>]
_spin_lock_irqsave+0x53/0x90
                                         [<ffffffff802a4216>]
ftrace_record_ip+0x196/0x2f0
                                         [<ffffffff8020c6b4>]
mcount_call+0x5/0x31
                                         [<ffffffff812e1c9b>]
kernel_init+0x14d/0x1b2
                                         [<ffffffff8020d919>] child_rip+0xa/0x11
                                         [<ffffffffffffffff>] 0xffffffffffffffff
    in-hardirq-W at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
    in-softirq-W at:
                                         [<ffffffffffffffff>] 0xffffffffffffffff
  }
  ... key      at: [<ffffffff8087c1b8>] ftrace_shutdown_lock+0x18/0x40
 ... acquired at:
   [<ffffffffffffffff>] 0xffffffffffffffff


stack backtrace:
Pid: 9, comm: rcu_sched_grace Not tainted 2.6.27-rc4-225c-debug #3

Call Trace:
 [<ffffffff8026d8b2>] print_irq_inversion_bug+0x142/0x160
 [<ffffffff8026dd27>] check_usage_backwards+0x67/0xb0
 [<ffffffff8026ebd3>] mark_lock+0x363/0x7f0
 [<ffffffff8026fae9>] __lock_acquire+0x4f9/0x1160
 [<ffffffff802707e1>] lock_acquire+0x91/0xc0
 [<ffffffff80466c2c>] ? free_object+0x7c/0xc0
 [<ffffffff806a2bb1>] _spin_lock+0x41/0x80
 [<ffffffff80466c2c>] ? free_object+0x7c/0xc0
 [<ffffffff806a6bc9>] ? sub_preempt_count+0x69/0xd0
 [<ffffffff80466c2c>] free_object+0x7c/0xc0
 [<ffffffff8046707e>] debug_object_free+0xbe/0x130
 [<ffffffff806a070e>] schedule_timeout+0x7e/0xe0
 [<ffffffff802503a0>] ? process_timeout+0x0/0x10
 [<ffffffff806a06f2>] ? schedule_timeout+0x62/0xe0
 [<ffffffff8029cf10>] ? rcu_sched_grace_period+0x0/0x3a0
 [<ffffffff806a07ce>] schedule_timeout_interruptible+0x1e/0x20
 [<ffffffff8029cfb2>] rcu_sched_grace_period+0xa2/0x3a0
 [<ffffffff8029cf10>] ? rcu_sched_grace_period+0x0/0x3a0
 [<ffffffff8025d50e>] kthread+0x4e/0x90
 [<ffffffff8020d919>] child_rip+0xa/0x11
 [<ffffffff80239b8f>] ? finish_task_switch+0x5f/0x120
 [<ffffffff806a356b>] ? _spin_unlock_irq+0x3b/0x70
 [<ffffffff8020cf23>] ? restore_args+0x0/0x30
 [<ffffffff8025d4c0>] ? kthread+0x0/0x90
 [<ffffffff8020d90f>] ? child_rip+0x0/0x11

--- [2]

procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----
 r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa
58  0  63972  17316     16 145172  128 21176   128 21176 6054 8662 79 21  0  0
47  2  81020  14380     16 139472 1120 17052  1240 17052 6106 9532 77 23  0  0
52  1  86276  33656     16 137140  604 5304   796  5304 5349 7954 81 19  0  0
94  0  86276  32192     16 137484  480    0   772     0 5418 7618 84 16  0  0
88  0  86264  22416     16 137800   96    0   396     0 4746 5937 87 13  0  0
63  1  86200  54636     16 137932 1380    0  1408     0 5472 8007 82 18  0  0
47  0  86020  22848     16 138132  256    0   312     0 6126 12227 72 28  0  0
75  2 103828  20252     16 135500  528 17836   592 17836 6655 12862 69 31  0  0
21  0 128568  17536     16 128888 2336 24732  2336 24732 6762 12891 66 34  0  0
159  0 154996  16888     16 124808  480 26236   504 26236 5930 7689 80 20  0  0
45  0 165616  40108     16 120544  192 10696   248 10696 6136 9163 77 23  0  0
95  0 165616  27296     16 120632  924    0   940     0 5293 7468 82 18  0  0
BUG: NMI Watchdog detected LOCKUP on CPU0, ip ffffffff80214407, registers:
CPU 0
Modules linked in: rfcomm l2cap bluetooth kvm_intel kvm microcode
dvb_usb_dtt200u dvb_usb uvcvideo dvb_core compat_ioctl32 i2c_core
videodev v4l1_compat shpchp pcig
Pid: 6948, comm: spiral Not tainted 2.6.27-rc4-225c-debug #3
RIP: 0010:[<ffffffff80214407>]  [<ffffffff80214407>] native_read_tsc+0x7/0x30
RSP: 0018:ffffffff8153ab70  EFLAGS: 00000002
RAX: 00000467c85cb001 RBX: ffffffff8088f5c0 RCX: 00000000c85cb001
RDX: 00000000c85cb001 RSI: 0000000000000103 RDI: 0000000000000001
RBP: ffffffff8153ab70 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8800cf978000 R12: 00000000c85cb001
R13: 0000000000000001 R14: 0000000000000000 R15: ffff88012a61c8c0
FS:  00007fb48cb796e0(0000) GS:ffffffff80e82dc0(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00000000075212e6 CR3: 00000000cc1e6000 CR4: 00000000000026e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
Process spiral (pid: 6948, threadinfo ffff8800cf950000, task ffff8800cf978000)
Stack:  ffffffff8153aba0 ffffffff804560c7 ffffffff8088f5c0 0000000005b61b94
 00000000d6915628 0000000000000001 ffffffff8153abb0 ffffffff80455fff
 ffffffff8153abe0 ffffffff80466302 ffffffff8088f5d8 ffffffff8088f5c0
Call Trace:
 <IRQ>  [<ffffffff804560c7>] delay_tsc+0x67/0xd0
 [<ffffffff80455fff>] __delay+0xf/0x20
 [<ffffffff80466302>] _raw_spin_lock+0x122/0x170
 [<ffffffff806a2bd1>] _spin_lock+0x61/0x80
 [<ffffffff80466c2c>] ? free_object+0x7c/0xc0
 [<ffffffff80466c2c>] free_object+0x7c/0xc0
 [<ffffffff80466e0f>] __debug_check_no_obj_freed+0x19f/0x1e0
 [<ffffffff80466e65>] debug_check_no_obj_freed+0x15/0x20
 [<ffffffff802dff0c>] kmem_cache_free+0xec/0x110
 [<ffffffff80517fa1>] ? scsi_pool_free_command+0x51/0x60
 [<ffffffff80517fa1>] scsi_pool_free_command+0x51/0x60
 [<ffffffff805184bf>] __scsi_put_command+0x5f/0xa0
 [<ffffffff80518561>] scsi_put_command+0x61/0x70
 [<ffffffff8051e47a>] scsi_next_command+0x3a/0x60
 [<ffffffff8051e544>] scsi_end_request+0xa4/0xc0
 [<ffffffff8051e68f>] scsi_io_completion+0x12f/0x440
 [<ffffffff80517bf5>] scsi_finish_command+0x95/0xd0
 [<ffffffff8051eb36>] scsi_softirq_done+0x86/0x110
 [<ffffffff8043bbed>] blk_done_softirq+0x8d/0xa0
 [<ffffffff8024ba04>] __do_softirq+0x74/0xf0
 [<ffffffff8020dc7c>] call_softirq+0x1c/0x30
 [<ffffffff8020f485>] do_softirq+0x75/0xb0
 [<ffffffff8024b155>] irq_exit+0xa5/0xb0
 [<ffffffff8020f7d3>] do_IRQ+0xe3/0x1d0
 [<ffffffff80466c66>] ? free_object+0xb6/0xc0
 [<ffffffff8020ce76>] ret_from_intr+0x0/0xf
 <EOI>  [<ffffffff80270ba0>] ? lock_release+0xe0/0x210
 [<ffffffff806a3253>] ? _spin_unlock+0x23/0x60
 [<ffffffff80466c66>] ? free_object+0xb6/0xc0
 [<ffffffff8046707e>] ? debug_object_free+0xbe/0x130
 [<ffffffff806a070e>] ? schedule_timeout+0x7e/0xe0
 [<ffffffff802503a0>] ? process_timeout+0x0/0x10
 [<ffffffff806a06f2>] ? schedule_timeout+0x62/0xe0
 [<ffffffff802f8b3e>] ? do_select+0x4be/0x610
 [<ffffffff802f8c90>] ? __pollwait+0x0/0x120
 [<ffffffff8026f1d9>] ? trace_hardirqs_on_caller+0x29/0x1b0
 [<ffffffff8026f1d9>] ? trace_hardirqs_on_caller+0x29/0x1b0
 [<ffffffff8026f36d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff806a0b9e>] ? mutex_unlock+0xe/0x10
 [<ffffffff8065919e>] ? unix_stream_recvmsg+0x32e/0x6d0
 [<ffffffff8026f1d9>] ? trace_hardirqs_on_caller+0x29/0x1b0
 [<ffffffff8026f36d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff802f8f4b>] ? core_sys_select+0x19b/0x2e0
 [<ffffffff802e89e9>] ? do_sync_read+0xf9/0x140
 [<ffffffff8025d8e0>] ? autoremove_wake_function+0x0/0x40
 [<ffffffff806a6bc9>] ? sub_preempt_count+0x69/0xd0
 [<ffffffff802f94b0>] ? sys_select+0xd0/0x1c0
 [<ffffffff8020c86b>] ? system_call_fastpath+0x16/0x1b


Code: 90 90 90 90 55 89 f8 48 89 e5 e6 70 e4 71 c9 c3 0f 1f 40 00 55
89 f0 48 89 e5 e6 70 89 f8 e6 71 c9 c3 66 90 55 48 89 e5 0f 1f 00 <0f>
ae e8 0f 31 89 c1 0f 1f
BUG: NMI Watchdog detected LOCKUP<4>---[ end trace fd851c3db62e5044 ]---
Kernel panic - not syncing: Aiee, killing interrupt handler!
 on CPU1, ip ffffffff80214407, registers:
CPU 1
Modules linked in: rfcomm l2cap bluetooth kvm_intel kvm microcode
dvb_usb_dtt200u dvb_usb uvcvideo dvb_core compat_ioctl32 i2c_core
videodev v4l1_compat shpchp pcig
Pid: 10150, comm: gcc Not tainted 2.6.27-rc4-225c-debug #3
RIP: 0010:[<ffffffff80214407>]  [<ffffffff80214407>] native_read_tsc+0x7/0x30
RSP: 0018:ffff8800b6269c28  EFLAGS: 00000092
RAX: 0000000000000001 RBX: ffffffff8088f5c0 RCX: 00000000c85cafc2
RDX: 000000008b468b00 RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffff8800b6269c28 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8800a65047e0 R12: 0000000005d22695
R13: 0000000000000001 R14: 0000000000000001 R15: ffff88009e9be940
FS:  00002b124e4fc6e0(0000) GS:ffff88012fa644b0(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00002b8a265f5960 CR3: 00000000b61e9000 CR4: 00000000000026e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process gcc (pid: 10150, threadinfo ffff8800b6268000, task ffff8800a65047e0)
Stack:  ffff8800b6269c58 ffffffff8045608a ffffffff8088f5c0 0000000005d22695
 00000000d6915628 0000000000000001 ffff8800b6269c68 ffffffff80455fff
 ffff8800b6269c98 ffffffff80466302 ffffffff8088f5d8 ffffffff8088f5c0
Call Trace:
 [<ffffffff8045608a>] delay_tsc+0x2a/0xd0
 [<ffffffff80455fff>] __delay+0xf/0x20
 [<ffffffff80466302>] _raw_spin_lock+0x122/0x170
 [<ffffffff806a2bd1>] _spin_lock+0x61/0x80
 [<ffffffff80466c2c>] ? free_object+0x7c/0xc0
 [<ffffffff80466c2c>] free_object+0x7c/0xc0
 [<ffffffff80466e0f>] __debug_check_no_obj_freed+0x19f/0x1e0
 [<ffffffff80466e65>] debug_check_no_obj_freed+0x15/0x20
 [<ffffffff802dff0c>] kmem_cache_free+0xec/0x110
 [<ffffffff8024264b>] ? __cleanup_signal+0x1b/0x20
 [<ffffffff8024264b>] __cleanup_signal+0x1b/0x20
 [<ffffffff80248273>] release_task+0x233/0x3d0
 [<ffffffff80248960>] wait_consider_task+0x550/0x8b0
 [<ffffffff80248e16>] do_wait+0x156/0x350
 [<ffffffff8023b6f0>] ? default_wake_function+0x0/0x10
 [<ffffffff802490a6>] sys_wait4+0x96/0xf0
 [<ffffffff8020c86b>] system_call_fastpath+0x16/0x1b


Code: 90 90 90 90 55 89 f8 48 89 e5 e6 70 e4 71 c9 c3 0f 1f 40 00 55
89 f0 48 89 e5 e6 70 89 f8 e6 71 c9 c3 66 90 55 48 89 e5 0f 1f 00 <0f>
ae e8 0f 31 89 c1 0f 1f
---[ end trace fd851c3db62e5044 ]---
-- 
Daniel J Blueman

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

Adding in SLUB debugging doesn't show anything new (I think). Example
boot log (w/ initcall_debug enabled) is at:

http://free.linux.hp.com/~adb/bug.11342/prob5.txt

This has happened 3 times in a row as well. Whilst this is being looked
at, I'm going to fast-forward ahead to the latest in Linus' tree, and
see if the problem is still occurring (I think Linus' point earlier
about some sort of rogue timing and/or corruption bug is spot on, but
it's probably better to see how close to "today's tree" I can reproduce
this). I'll also try kernels w/ the problematic merge patch backed out
to see if that still "fixes" (or more likely(?) just patches over the
real problem).

Alan

Re: [Bug #11356] Linux 2.6.27-rc3 - build failure: undefined reference to `.lockdep_count_forward_deps'

[Adrian Bunk]

On Sun, Aug 24, 2008 at 08:13:55AM +0200, Frans Pop wrote:
> On Saturday 23 August 2008, Rafael J. Wysocki wrote:
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11356
> > Subject	: Linux 2.6.27-rc3 - build failure: undefined reference to
> > 		  `.lockdep_count_forward_deps'
> > Submitter	: Frans Pop <elendil@planet.nl> 
> > Date		: 2008-08-16 19:11 (8 days old)
> > References	: http://marc.info/?l=linux-kernel&m=121891396320127&w=4
> 
> Fixed as per: http://marc.info/?l=linux-kernel&m=121898767530602&w=4
> Adrian mentioned that he'd closed the bug, but apparently not.

Sorry, I missed that Rafael had opened two bugs for two people reporting 
the same issue, and only closed the other one.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

I built a kernel @

commit 83097aca8567a0bd593534853b71fe0fa9a75d69
Author: Arjan van de Ven <arjan@linux.intel.com>
Date:   Sat Aug 23 21:45:21 2008 -0700

And it fails like the others do

o  http://free.linux.hp.com/~adb/bug.11342/prob6.txt

SMP_DEBUG_PAGEALLOC

o  http://free.linux.hp.com/~adb/bug.11342/prob6a.txt

[    7.591198] BUG: unable to handle kernel NULL pointer dereference at
0000000000000858



I then backed out /just/ the merge for

commit 1c89ac55017f982355c7761e1c912c88c941483d
Merge: 88fa08f... b1b135c...
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue Aug 12 08:40:19 2008 -0700

And the machine has booted fine 5 times in a row.



I've put the latest .config up at

http://free.linux.hp.com/~adb/bug.11342/config.txt


Is there /some/ way to break down the patches within the merged patch,
and I could by-hand bisect through those?

Here's what I did to take the latest tree, and back out that merge (to
get booting kernels):

git-diff
88fa08f67bee1a0c765237bdac106a32872f57d2..1c89ac55017f982355c7761e1c912c88c941483d
| patch -p1 -R
patching file Documentation/lguest/lguest.c
patching file arch/powerpc/Kconfig
patching file arch/x86/Kconfig
patching file arch/x86/mm/Makefile
patching file drivers/char/hvc_console.c
patching file drivers/lguest/page_tables.c
patching file include/linux/Kbuild
Hunk #1 succeeded at 358 (offset 2 lines).
patching file include/linux/init.h
patching file include/linux/mm.h
patching file init/main.c
patching file kernel/module.c
patching file kernel/stop_machine.c
patching file mm/Kconfig
patching file mm/util.c

Alan

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Mon, 25 Aug 2008, Alan D. Brunelle wrote:
>
> Before adding any more debugging, this is the status of my kernel boots:
> 3 times in a row w/ this same error. (Primary problem is the same,
> secondary stacks differ of course.)

Ok, so I took a closer look, and the oops really is suggestive..

> [    6.482953] busybox used greatest stack depth: 4840 bytes left

Ok, 4840 bytes left out of 8kB.

> [    6.521876] all_generic_ide used greatest stack depth: 4784 bytes left

.. and this one is 4784 bytes left..

> Begin: Loading essential drivers... ...
> [    6.625509] fuse init (API version 7.9)
> [    6.625509] modprobe used greatest stack depth: 1720 bytes left

Uhhuh! The previous "modprobe" uses stack like mad.  It could be 
"fuse_init()" that has done it, but looking at fuse, I seriously doubt it. 
It doesn't seem to do anything particularly bad.

So something has used over 6kB of stack, and it may well be the module 
loading code itself.

The next stage is the actual oops itself:

> [    6.644854] ACPI: SSDT CFFD0D0A, 08C4 (r1 HPQOEM  CPU_TM2        1 MSFT  100000E)
> [    6.651489] BUG: unable to handle kernel NULL pointer dereference at 0000000000000858

This really looks like

	ti->task->blocked_on = waiter;

where "ti->task" is NULL. You probably have almost everything enabled in 
order to turn "struct task_struct" that big, but judging by your register 
state it's really an offset off a NULL pointer, not some small integer.

Now, there is no way "ti->task" can _possibly_ be NULL. No way.

Well, except that "ti" is just below the stack, and if you had a stack 
overflow that overwrote it.

So I seriously do believe that you have run out of stack. If that is true, 
then it's quite likely that with DEBUG_PAGE_ALLOC you'll actually get a 
double fault, which in turn is fairly hard to debug (you look at it wrong 
and it turns into a triple fault which is going to just reboot your 
machine immediately).

Now, the stack oveflow probably happened a few calls earlier (and just 
left your thread_info corrupted), but there is more reason to believe you 
have stack overflow and thread_info corruption later in your output:

> [    7.024992] modprobe used greatest stack depth: 408 bytes left  
> [    7.030988] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
> [    7.031053] IP: [<ffffffff8023f39c>] do_exit+0x28c/0xa10

Here there is only 408 bytes left, which is _way_ too little, but it's 
also an optimistic measure. What the stack code usage code does is to just 
see how many zeroes it can find on the stack. If you have a big stack 
frame somewhere, it's quite possible that it actually used all your stack 
and then some, but left a bunch of zeroes around.

And the do_exit() oops is simply because once the thread_info is 
corrupted, all the basic thread data structures are crap, and yes, you're 
almost guaranteed to oops at that point.

Could you make your kernel image available somewhere, and we can take a 
look at it? Some versions of gcc are total pigs when it comes to stack 
usage, and your exact configuration matters too.  But yes, module loading 
is a bad case, for me "sys_init_module()" contains

	subq    $392, %rsp      #,

which is probably mostly because of the insane inlining gcc does (ie it 
will likely have inlined every single function in that file that is only 
called once, and then it will make all local variables of all those 
functions alive over the whole function and allocate stack-space for them 
ALL AT THE SAME TIME).

Gcc sometimes drives me mad. It's inlining decisions are almost always 
pure and utter sh*t. But clearly something changed for you to start 
triggering this, and I think that also explains why you bisected things to 
the merge commit rather than to any individual change - because it was 
probably not any individual change that pushed it over the limit, but two 
different changes that made for bigger stack pressure, and _together_ they 
pushed you over the limit.

So it also explains why the merge you found had no possible merge errors 
on a source level - there were no actual clashes anywhere. Just a slow 
growth of stack that combined to something that overflowed.

And yes, I bet the change by Arjan to use do_one_initcall() was _part_ of 
it. It adds roughly 112 bytes of stack pressure to that module loading 
path, because of the 64-byte array and the extra function call (8 bytes 
for return address) with at least 5 quad-words saved (40 bytes) for 
register spills.

But there were probably other things happening too that made things worse.

So if there is some place where you can upload your 'vmlinux' binary, it 
would be good.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Mon, 25 Aug 2008, Alan D. Brunelle wrote:
> 
> With /just/ DEBUG_PAGE_ALLOC defined, I have seen two general panic types:
> 
> o  A new double fault w/ SMP_DEBUG_PAGEALLOC problem (prob4.txt)

Yeah, that's a stack overflow.

Confirmed.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Mon, 25 Aug 2008, Linus Torvalds wrote:
> 
> Could you make your kernel image available somewhere, and we can take a 
> look at it? Some versions of gcc are total pigs when it comes to stack 
> usage, and your exact configuration matters too.  But yes, module loading 
> is a bad case, for me "sys_init_module()" contains
> 
> 	subq    $392, %rsp      #,
> 
> which is probably mostly because of the insane inlining gcc does (ie it 
> will likely have inlined every single function in that file that is only 
> called once, and then it will make all local variables of all those 
> functions alive over the whole function and allocate stack-space for them 
> ALL AT THE SAME TIME).

I bet this one-liner will probably make your kernel work. It's not a full 
solution, but it will make the module-loading path lose _all_ of the above 
stack slots by just not inlining "load_module()" - the stack slots will 
still be used when the module is _loaded_, but by the time we actually 
callt he ->init function they will have been released since it's not all 
in the same crazy function any more.

I _seriously_ believe that we were better off back when gcc only inlined 
what we told it to inline, and never inlined on its own. The gcc inlining 
logic is pure and utter sh*t in an environment like the kernel where stack 
space is a valuable resource.

Anyway, Alan, even if this solves your particular problem, I'd still like 
to see your kernel image, so that I can hunt for other problems like 
this..

			Linus

---
 kernel/module.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/module.c b/kernel/module.c
index 08864d2..9db1191 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1799,7 +1799,7 @@ static void *module_alloc_update_bounds(unsigned long size)
 
 /* Allocate and load the module: note that size of section 0 is always
    zero, and we rely on this for optional sections. */
-static struct module *load_module(void __user *umod,
+static noinline struct module *load_module(void __user *umod,
 				  unsigned long len,
 				  const char __user *uargs)
 {

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

Linus Torvalds wrote:
> 
> On Mon, 25 Aug 2008, Linus Torvalds wrote:
>> Could you make your kernel image available somewhere, and we can take a 
>> look at it? Some versions of gcc are total pigs when it comes to stack 
>> usage, and your exact configuration matters too.  But yes, module loading 
>> is a bad case, for me "sys_init_module()" contains
>>
>> 	subq    $392, %rsp      #,
>>
>> which is probably mostly because of the insane inlining gcc does (ie it 
>> will likely have inlined every single function in that file that is only 
>> called once, and then it will make all local variables of all those 
>> functions alive over the whole function and allocate stack-space for them 
>> ALL AT THE SAME TIME).

Mine has:

Dump of assembler code for function sys_init_module:
0xffffffff802688c0 <sys_init_module+0>:	push   %rbp
0xffffffff802688c1 <sys_init_module+1>:	mov    %rsp,%rbp
0xffffffff802688c4 <sys_init_module+4>:	sub    $0x1c0,%rsp
0xffffffff802688cb <sys_init_module+11>:	mov    %r12,-0x20(%rbp)
0xffffffff802688cf <sys_init_module+15>:	mov    %rdi,%r12

so 448 bytes.

The kernel is up at: http://free.linux.hp.com/~adb/bug.11342/vmlinux (if
you would let me know when you are through with it so I can free up some
space there I'd appreciate it...)

By doing the patch you provided, sys_init_module now looks like:

Dump of assembler code for function sys_init_module:
0xffffffff8026aa20 <sys_init_module+0>:	push   %rbp
0xffffffff8026aa21 <sys_init_module+1>:	mov    %rsp,%rbp
0xffffffff8026aa24 <sys_init_module+4>:	sub    $0x20,%rsp
0xffffffff8026aa28 <sys_init_module+8>:	mov    %r14,0x18(%rsp)
0xffffffff8026aa2d <sys_init_module+13>:	mov    %rdi,%r14


So only 32 bytes. (But of course, load_module() exists, and now has
0x1d0 (464) bytes...)

With the patch you provide, I /was/ able to repeatedly boot OK (latest
tree, and I also ran the patch against the 26.27.rc3-based kernel I was
having problems with initially, and that booted OK as well).

Alan

> 
> I bet this one-liner will probably make your kernel work. It's not a full 
> solution, but it will make the module-loading path lose _all_ of the above 
> stack slots by just not inlining "load_module()" - the stack slots will 
> still be used when the module is _loaded_, but by the time we actually 
> callt he ->init function they will have been released since it's not all 
> in the same crazy function any more.
> 
> I _seriously_ believe that we were better off back when gcc only inlined 
> what we told it to inline, and never inlined on its own. The gcc inlining 
> logic is pure and utter sh*t in an environment like the kernel where stack 
> space is a valuable resource.
> 
> Anyway, Alan, even if this solves your particular problem, I'd still like 
> to see your kernel image, so that I can hunt for other problems like 
> this..
> 
> 			Linus
> 
> ---
>  kernel/module.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/kernel/module.c b/kernel/module.c
> index 08864d2..9db1191 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -1799,7 +1799,7 @@ static void *module_alloc_update_bounds(unsigned long size)
>  
>  /* Allocate and load the module: note that size of section 0 is always
>     zero, and we rely on this for optional sections. */
> -static struct module *load_module(void __user *umod,
> +static noinline struct module *load_module(void __user *umod,
>  				  unsigned long len,
>  				  const char __user *uargs)
>  {
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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> Please read the FAQ at  http://www.tux.org/lkml/

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Mon, 25 Aug 2008, Alan D. Brunelle wrote:
> 
> Mine has:
> 
> Dump of assembler code for function sys_init_module:
> 0xffffffff802688c4 <sys_init_module+4>:	sub    $0x1c0,%rsp
> 
> so 448 bytes.

Yeah, your build seems to have consistently bigger stack usage, and that 
may be due to some config option, but most likely it's a compiler version 
issue.

But I think part of the reason is that you have frame pointers enabled: 
that makes the stack frames bigger not only because of the frame pointer 
save/restore, but also because you have more register pressure and thus 
spills.

> The kernel is up at: http://free.linux.hp.com/~adb/bug.11342/vmlinux (if
> you would let me know when you are through with it so I can free up some
> space there I'd appreciate it...)

I'm downloading it now, I'll probably be done by the time you get this 
email.

[ Update. Done. You can remove it ]

> By doing the patch you provided, sys_init_module now looks like:
> 
> Dump of assembler code for function sys_init_module:
> 0xffffffff8026aa24 <sys_init_module+4>:	sub    $0x20,%rsp
> 
> So only 32 bytes. (But of course, load_module() exists, and now has
> 0x1d0 (464) bytes...)

Right - the stack usage didn't go away, but the _lifetimes_ changed.

So now load_module() will still use almost 500 bytes of stack, and it will 
call other routines that use stack too, but the lifetime of that stack 
usage is no longer over the whole module loading and initialization part, 
it's purely over just the loading thing.

And since the deep callchain came much later (in the actual ->init 
routines), by the time we do that, we no longer now have the load_module 
stack usage active any more.

> With the patch you provide, I /was/ able to repeatedly boot OK (latest
> tree, and I also ran the patch against the 26.27.rc3-based kernel I was
> having problems with initially, and that booted OK as well).

I had actually already committed it, because it was correct regardless 
(and gcc really is a total ass for doing that inlining to begin with), but 
it's good to have verification that the behaviour you saw was literally 
about this thing.

I'll look at your vmlinux binary to see what else sucks from a stack depth 
standpoint, but one of the problems in this whole thing is that the 
stack usage is obviously both a static thing (with some functions using 
_way_ too much stack!) _and_ a dynamic thing (with the total stack use 
being not about any individual function, but the whole chain).

My patch obviously doesn't change the static stack usage, it just moves it 
around a bit so that it's no longer on that same deep path, so the dynamic 
stack usage is much less.

But I'll look at your vmlinux, see what stands out.

		Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Arjan van de Ven]

Linus Torvalds wrote:
> On Mon, 25 Aug 2008, Alan D. Brunelle wrote:
>> Mine has:
>>
>> Dump of assembler code for function sys_init_module:
>> 0xffffffff802688c4 <sys_init_module+4>:	sub    $0x1c0,%rsp
>>
>> so 448 bytes.
> 
> Yeah, your build seems to have consistently bigger stack usage, and that 
> may be due to some config option, but most likely it's a compiler version 
> issue.
> 

I wonder if we ought to have a light version of "make checkstack" always run,
but in such a way that we make a file with "limits" on the stack usage for key
functions (and we can grow this list over time when we learn about critical ones)..
and either warn very loudly or even fail the build if we're way over what could work.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Mon, 25 Aug 2008, Linus Torvalds wrote:
> 
> But I'll look at your vmlinux, see what stands out.

Oops. I already see the problem.

Your .config has soem _huge_ CPU count, doesn't it?

checkstack.pl shows these things as the top problems:

	0xffffffff80266234 smp_call_function_mask [vmlinux]:    2736
	0xffffffff80234747 __build_sched_domains [vmlinux]:     2232
	0xffffffff8023523f __build_sched_domains [vmlinux]:     2232
	0xffffffff8021e884 setup_IO_APIC_irq [vmlinux]:         1616
	0xffffffff8021ee24 arch_setup_ht_irq [vmlinux]:         1600
	0xffffffff8021f144 arch_setup_msi_irq [vmlinux]:        1600
	0xffffffff8021e3b0 __assign_irq_vector [vmlinux]:       1592
	0xffffffff8021e626 __assign_irq_vector [vmlinux]:       1592
	0xffffffff8023257e move_task_off_dead_cpu [vmlinux]:    1592
	0xffffffff802326e8 move_task_off_dead_cpu [vmlinux]:    1592
	0xffffffff8025dbc5 tick_handle_oneshot_broadcast [vmlinux]:1544
	0xffffffff8025dcb4 tick_handle_oneshot_broadcast [vmlinux]:1544
	0xffffffff803f3dc4 store_scaling_governor [vmlinux]:    1376
	0xffffffff80279ef4 cpuset_write_resmask [vmlinux]:      1360
	0xffffffff803f465d cpufreq_add_dev [vmlinux]:           1352
	0xffffffff803f495b cpufreq_add_dev [vmlinux]:           1352
	0xffffffff803f3fc4 store_scaling_max_freq [vmlinux]:    1328
	0xffffffff803f4064 store_scaling_min_freq [vmlinux]:    1328
	0xffffffff803f44c4 cpufreq_update_policy [vmlinux]:     1328
	..

and sys_init_module is actually way way down the list. I bet the only 
reason it showed up at all was because dynamically it was such a deep 
callchain, and part of that callchain probably called some of those really 
nasty things.

Anyway, the reason smp_call_function_mask and friends have such _huge_ 
stack usages for you is that they contain a 'cpumask_t' on the stack.

For example, for me, usign a sane NR_CPU, the size of the stack frame for 
smp_call_function_mask is under 200 bytes.  For you, it's 2736 bytes.

How about you make CONFIG_NR_CPU's something _sane_? Like 16? Or do you 
really have four thousand CPU's in that system?

Oh, I guess you have the MAXSMP config enabled? I really think that was a 
bit too aggressive.

		Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Mon, 25 Aug 2008, Linus Torvalds wrote:
> 
> checkstack.pl shows these things as the top problems:
> 
> 	0xffffffff80266234 smp_call_function_mask [vmlinux]:    2736
> 	0xffffffff80234747 __build_sched_domains [vmlinux]:     2232
> 	0xffffffff8023523f __build_sched_domains [vmlinux]:     2232
> 
> Anyway, the reason smp_call_function_mask and friends have such _huge_ 
> stack usages for you is that they contain a 'cpumask_t' on the stack.

In fact, they contain multiple CPU-masks, each 4k-bits - 512 bytes - in 
size. And they tend to call each other.

Quite frankly, I don't think we were really ready for 4k CPU's. I'm going 
to commit this patch to make sure others don't do that many CPU's by 
mistake. It marks MAXCPU's as being 'broken' so you cannot select it, and 
also limits the number of CPU's that you _can_ select to "just" 512.

Right now, 4k cpu's is known broken because of the stack usage. I'm not 
willing to debug more of these kinds of stack smashers, they're really 
nasty to work with. I wonder how many other random failures these have 
been involved with?

This patch also makes the ifdef mess in Kconfig much cleaner and avoids 
duplicate definitions by just conditionally suppressing the question and 
giving higher defaults. 

We can enable MAXSMP and raise the CPU limits some time in the future. But 
that future is not going to be before 2.6.27 - the code simply isn't ready 
for it.

The reason I picked 512 CPU's as the limit is that we _used_ to limit 
things to 255. So it's higher than it used to be, but low enough to still 
feel safe. Considering that a 4k-bit CPU mask (512 bytes) _almost_ worked, 
the 512-bit (64 bytes) masks are almost certainly fine.

Still, sane people should limit their NR_CPUS to 8 or 16 or something like 
that. Very very few people really need the pain of big NR_CPUS. Not even 
"just" 512 CPU's.

Travis, Ingo and Thomas cc'd, since they were involved in the original 
commit (1184dc2ffe2c8fb9afb766d870850f2c3165ef25) that raised the limit.

		Linus

---
 arch/x86/Kconfig |   30 ++++++++----------------------
 1 files changed, 8 insertions(+), 22 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 68d91c8..ed92864 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -577,35 +577,29 @@ config SWIOTLB
 
 config IOMMU_HELPER
 	def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
+
 config MAXSMP
 	bool "Configure Maximum number of SMP Processors and NUMA Nodes"
-	depends on X86_64 && SMP
+	depends on X86_64 && SMP && BROKEN
 	default n
 	help
 	  Configure maximum number of CPUS and NUMA Nodes for this architecture.
 	  If unsure, say N.
 
-if MAXSMP
-config NR_CPUS
-	int
-	default "4096"
-endif
-
-if !MAXSMP
 config NR_CPUS
-	int "Maximum number of CPUs (2-4096)"
-	range 2 4096
+	int "Maximum number of CPUs (2-512)" if !MAXSMP
+	range 2 512
 	depends on SMP
+	default "4096" if MAXSMP
 	default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
 	default "8"
 	help
 	  This allows you to specify the maximum number of CPUs which this
-	  kernel will support.  The maximum supported value is 4096 and the
+	  kernel will support.  The maximum supported value is 512 and the
 	  minimum value which makes sense is 2.
 
 	  This is purely to save memory - each supported CPU adds
 	  approximately eight kilobytes to the kernel image.
-endif
 
 config SCHED_SMT
 	bool "SMT (Hyperthreading) scheduler support"
@@ -996,17 +990,10 @@ config NUMA_EMU
 	  into virtual nodes when booted with "numa=fake=N", where N is the
 	  number of nodes. This is only useful for debugging.
 
-if MAXSMP
-
 config NODES_SHIFT
-	int
-	default "9"
-endif
-
-if !MAXSMP
-config NODES_SHIFT
-	int "Maximum NUMA Nodes (as a power of 2)"
+	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
 	range 1 9   if X86_64
+	default "9" if MAXSMP
 	default "6" if X86_64
 	default "4" if X86_NUMAQ
 	default "3"
@@ -1014,7 +1001,6 @@ config NODES_SHIFT
 	help
 	  Specify the maximum number of NUMA Nodes available on the target
 	  system.  Increases memory reserved to accomodate various tables.
-endif
 
 config HAVE_ARCH_BOOTMEM_NODE
 	def_bool y

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan D. Brunelle]

Linus Torvalds wrote:
> 
> On Mon, 25 Aug 2008, Linus Torvalds wrote:
>> But I'll look at your vmlinux, see what stands out.
> 
> Oops. I already see the problem.
> 
> Your .config has soem _huge_ CPU count, doesn't it?
> 
> checkstack.pl shows these things as the top problems:
> 
> 	0xffffffff80266234 smp_call_function_mask [vmlinux]:    2736
> 	0xffffffff80234747 __build_sched_domains [vmlinux]:     2232
> 	0xffffffff8023523f __build_sched_domains [vmlinux]:     2232
> 	0xffffffff8021e884 setup_IO_APIC_irq [vmlinux]:         1616
> 	0xffffffff8021ee24 arch_setup_ht_irq [vmlinux]:         1600
> 	0xffffffff8021f144 arch_setup_msi_irq [vmlinux]:        1600
> 	0xffffffff8021e3b0 __assign_irq_vector [vmlinux]:       1592
> 	0xffffffff8021e626 __assign_irq_vector [vmlinux]:       1592
> 	0xffffffff8023257e move_task_off_dead_cpu [vmlinux]:    1592
> 	0xffffffff802326e8 move_task_off_dead_cpu [vmlinux]:    1592
> 	0xffffffff8025dbc5 tick_handle_oneshot_broadcast [vmlinux]:1544
> 	0xffffffff8025dcb4 tick_handle_oneshot_broadcast [vmlinux]:1544
> 	0xffffffff803f3dc4 store_scaling_governor [vmlinux]:    1376
> 	0xffffffff80279ef4 cpuset_write_resmask [vmlinux]:      1360
> 	0xffffffff803f465d cpufreq_add_dev [vmlinux]:           1352
> 	0xffffffff803f495b cpufreq_add_dev [vmlinux]:           1352
> 	0xffffffff803f3fc4 store_scaling_max_freq [vmlinux]:    1328
> 	0xffffffff803f4064 store_scaling_min_freq [vmlinux]:    1328
> 	0xffffffff803f44c4 cpufreq_update_policy [vmlinux]:     1328
> 	..
> 
> and sys_init_module is actually way way down the list. I bet the only 
> reason it showed up at all was because dynamically it was such a deep 
> callchain, and part of that callchain probably called some of those really 
> nasty things.
> 
> Anyway, the reason smp_call_function_mask and friends have such _huge_ 
> stack usages for you is that they contain a 'cpumask_t' on the stack.
> 
> For example, for me, usign a sane NR_CPU, the size of the stack frame for 
> smp_call_function_mask is under 200 bytes.  For you, it's 2736 bytes.
> 
> How about you make CONFIG_NR_CPU's something _sane_? Like 16? Or do you 
> really have four thousand CPU's in that system?
> 
> Oh, I guess you have the MAXSMP config enabled? I really think that was a 
> bit too aggressive.
> 
> 		Linus

This probably all started when I was working on a software tool (aiod)
that was failing because somebody ELSE had 4,096 CPUs configured.
[[Seems that gcc had/has? it's MAX CPU value set to 1,024 (bits/sched.h
__CPU_SETSIZE), so when you issue system calls like sched_getaffinity,
it will "fail" for systems configured w/ 4,096 CPUs. I worked around it
by simply forgetting about the gcc values, and kept allocating larger
CPU masks until it worked.]]

I think you're right: the kernel as a whole may not be ready for 4,096
CPUs apparently...

Thanks for taking the time to look into this...

Alan

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Christoph Lameter]

Alan D. Brunelle wrote:

> I think you're right: the kernel as a whole may not be ready for 4,096
> CPUs apparently...

Mike has been working diligently on getting all these cpumasks off the stack
for the last months and has created an infrastructure to do this. So I think
we are close. It might just be a matter of merging some more patches that are
still left in Ingo's tree.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Rusty Russell]

On Tuesday 26 August 2008 06:43:03 Linus Torvalds wrote:
> So now load_module() will still use almost 500 bytes of stack

Hmm, wants neatening anyway; I'll see if I can reduce stack usage side effect.

Your workaround is very random, and that scares me.  I think a huge number of 
CPUs needs a real solution (an actual cpumask allocator, then do something 
clever if we come across an actual fastpath).

Thanks,
Rusty.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Ingo Molnar]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Mon, 25 Aug 2008, Linus Torvalds wrote:
> > 
> > checkstack.pl shows these things as the top problems:
> > 
> > 	0xffffffff80266234 smp_call_function_mask [vmlinux]:    2736
> > 	0xffffffff80234747 __build_sched_domains [vmlinux]:     2232
> > 	0xffffffff8023523f __build_sched_domains [vmlinux]:     2232
> > 
> > Anyway, the reason smp_call_function_mask and friends have such _huge_ 
> > stack usages for you is that they contain a 'cpumask_t' on the stack.
> 
> In fact, they contain multiple CPU-masks, each 4k-bits - 512 bytes - in 
> size. And they tend to call each other.
> 
> Quite frankly, I don't think we were really ready for 4k CPU's. I'm 
> going to commit this patch to make sure others don't do that many 
> CPU's by mistake. It marks MAXCPU's as being 'broken' so you cannot 
> select it, and also limits the number of CPU's that you _can_ select 
> to "just" 512.

yeah, that's OK i guess - distros can still enable 4K support if they 
wish to. Someone interested in improving the stack footprint situation 
should dust off the max-stack-footprint tracer so that we can catch 
these things in a more structured way.

And i guess the next generation of 4K CPUs support should just get away 
from cpumask_t-on-kernel-stack model altogether, as the current model is 
not maintainable. We tried the on-kernel-stack variant, and it really 
does not work reliably. We can fix this in v2.6.28.

	Ingo

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[David Miller]

From: Ingo Molnar <mingo@elte.hu>
Date: Tue, 26 Aug 2008 09:22:20 +0200

> And i guess the next generation of 4K CPUs support should just get away 
> from cpumask_t-on-kernel-stack model altogether, as the current model is 
> not maintainable. We tried the on-kernel-stack variant, and it really 
> does not work reliably. We can fix this in v2.6.28.

I recenetly did some work on sparc64 to use cpumask pointers
as much as possible.

The only case that didn't work was due to a limitation in
arch interfaces for the new generic smp_call_function() code.
It passes a cpumask_t instead of a pointer to one via
arch_send_call_function_ipi().

But other than that, the whole sparc64 SMP stuff uses cpumask_t
pointers only.

What it comes down to is that you have to do the "self cpu"
and other tests in the cross-call dispatch routines themselves,
instead of at the top-level working on cpumask_t objects.

Otherwise you have to modify cpumask_t objects and thus pluck
them onto the stack where they take up silly amounts of space.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Ingo Molnar]

* David Miller <davem@davemloft.net> wrote:

> From: Ingo Molnar <mingo@elte.hu>
> Date: Tue, 26 Aug 2008 09:22:20 +0200
> 
> > And i guess the next generation of 4K CPUs support should just get away 
> > from cpumask_t-on-kernel-stack model altogether, as the current model is 
> > not maintainable. We tried the on-kernel-stack variant, and it really 
> > does not work reliably. We can fix this in v2.6.28.
> 
> I recenetly did some work on sparc64 to use cpumask pointers as much 
> as possible.
> 
> The only case that didn't work was due to a limitation in arch 
> interfaces for the new generic smp_call_function() code. It passes a 
> cpumask_t instead of a pointer to one via 
> arch_send_call_function_ipi().
> 
> But other than that, the whole sparc64 SMP stuff uses cpumask_t 
> pointers only.

nice!

> What it comes down to is that you have to do the "self cpu" and other 
> tests in the cross-call dispatch routines themselves, instead of at 
> the top-level working on cpumask_t objects.
> 
> Otherwise you have to modify cpumask_t objects and thus pluck them 
> onto the stack where they take up silly amounts of space.

What we did was this: we added MAXSMP which just revs up all the SMP 
tunables to the maximum, so that we can see any problems early in 
testing.

And we triggered problems, and we fixed a couple of regressions all 
around stack footprint. But we didnt catch all of them - some were gcc 
version dependent and configuration dependent. So i think it's safe to 
say that the whole concept of allowing such a large cpumask_t to be on 
the stack is fragile.

Hence, i think the best way forward is to change the whole cpumask_t 
concept and disallow explicit masks altogether. It's so easy to smack a 
cpumask_t variable on the stack and nothing really warns about it, and 
any function can become part of a nested call sequence.

So i think the dynamics of it has to be changed: we need a get/put API 
and we need to make on-stack cpumask illegal on the build level (in 
generic code at least). This has been Rusty's main argument early on i 
think, and i now concur.

	Ingo

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Ingo Molnar]

* Christoph Lameter <cl@linux-foundation.org> wrote:

> Alan D. Brunelle wrote:
> 
> > I think you're right: the kernel as a whole may not be ready for 4,096
> > CPUs apparently...
> 
> Mike has been working diligently on getting all these cpumasks off the 
> stack for the last months and has created an infrastructure to do 
> this. So I think we are close. It might just be a matter of merging 
> some more patches that are still left in Ingo's tree.

hm, there are no such patches left that i know of - the only bits in 
-tip are the zero-based percpu, which was found to be a bit fragile in 
testing:

 earth4:~/tip> git-log-line --author=Travis linus..
 d379497: Zero based percpu: infrastructure to rebase the per cpu area to zero
 b3a0cb4: x86: extend percpu ops to 64 bit

[and it has no relevance to stack footprint.]

So i dont think the current cpumask_t approach will work. We simply 
should not get into an endless fight against the windmills that 
introduce on-stack cpumask_t again and again. We should just take the 
plunge once and do a clean alloc/free cpumask model. Most of the hotpath 
cpumasks are constant or pre-constructed, so they are not a real issue.

Plus, on the general question of stack footprint problems and the 
difficulty of debugging them, the worst-case stack footprint tracer i 
wrote for -rt some time ago should be dusted off as well and put into 
ftrace. David has something quite close to that for Sparc64 already.

	Ingo

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Yinghai Lu]

On Tue, Aug 26, 2008 at 12:53 AM, Ingo Molnar <mingo@elte.hu> wrote:
>
> * David Miller <davem@davemloft.net> wrote:
>
>> From: Ingo Molnar <mingo@elte.hu>
>> Date: Tue, 26 Aug 2008 09:22:20 +0200
>>
>> > And i guess the next generation of 4K CPUs support should just get away
>> > from cpumask_t-on-kernel-stack model altogether, as the current model is
>> > not maintainable. We tried the on-kernel-stack variant, and it really
>> > does not work reliably. We can fix this in v2.6.28.
>>
>> I recenetly did some work on sparc64 to use cpumask pointers as much
>> as possible.
>>
>> The only case that didn't work was due to a limitation in arch
>> interfaces for the new generic smp_call_function() code. It passes a
>> cpumask_t instead of a pointer to one via
>> arch_send_call_function_ipi().
>>
>> But other than that, the whole sparc64 SMP stuff uses cpumask_t
>> pointers only.

wonder if could use "unsigned long *" directly.
so could dyn_array directly like

int cpumask_size;

unsigned long *online_cpu_map;
DEFINE_DYN_ARRAY(online_cpu_map, sizeof(unsigned long), cpumask_size,
PAGE_SIZE, NULL);

and after nr_cpu_ids is assigned, have
cpumask_size = (nr_cpu_ids + sizeof(unsigned long) - 1)/sizeof(unsigned long);

then we could NR_CPUS=4096 kernel to small system. ...

YH

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Yinghai Lu wrote:
> 
> wonder if could use "unsigned long *" directly.

I would actually suggest something like this:

 - we continue to have a magic "cpumask_t".

 - we do different cases for big and small NR_CPUS:

	#if NR_CPUS <= BITS_PER_LONG

	/*
	 * Make it an array - that way passing it as an argument will
	 * always pass it as a pointer!
	 */
	typedef unsigned long cpumask_t[1];

	static inline void create_cpumask(cpumask_t *p)
	{
		*p = 0;
	}
	static inline void free_cpumask(cpumask_t *p)
	{
	}

	#else

	typedef unsigned long *cpumask_t;

	static inline void create_cpumask(cpumask_t *p)
	{
		*p = kcalloc(..);
	}

	static inline void free_cpumask(cpumask_t *p)
	{
		kfree(*p);
	}

	#endif

and now after you do this, you can just do something like

	cpumask_t mycpu;

	create_cpumask(&mycpu);
	..
	free_cpumask(&mycpu);

and in between, you can use 'cpumask' as a pointer, because even when it 
is an array directly allocated on the stack, the array can always 
degenerate into a pointer by C type rules!

And for the small-NR_CPUS case there is zero overhead.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Yinghai Lu]

On Tue, Aug 26, 2008 at 9:51 AM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
>
> On Tue, 26 Aug 2008, Yinghai Lu wrote:
>>
>> wonder if could use "unsigned long *" directly.
>
> I would actually suggest something like this:
>
>  - we continue to have a magic "cpumask_t".
>
>  - we do different cases for big and small NR_CPUS:
>
>        #if NR_CPUS <= BITS_PER_LONG
>
>        /*
>         * Make it an array - that way passing it as an argument will
>         * always pass it as a pointer!
>         */
>        typedef unsigned long cpumask_t[1];
>
>        static inline void create_cpumask(cpumask_t *p)
>        {
>                *p = 0;
>        }
>        static inline void free_cpumask(cpumask_t *p)
>        {
>        }
>
>        #else
>
>        typedef unsigned long *cpumask_t;
>
>        static inline void create_cpumask(cpumask_t *p)
>        {
>                *p = kcalloc(..);
>        }
>
>        static inline void free_cpumask(cpumask_t *p)
>        {
>                kfree(*p);
>        }
>
>        #endif
>
> and now after you do this, you can just do something like
>
>        cpumask_t mycpu;
>
>        create_cpumask(&mycpu);
>        ..
>        free_cpumask(&mycpu);
>
> and in between, you can use 'cpumask' as a pointer, because even when it
> is an array directly allocated on the stack, the array can always
> degenerate into a pointer by C type rules!
>

that is good for local variables.

for global variables, need to allocate them in some point. may need one
int cpumask_size;

cpumask_t online_cpu_map;
DEFINE_DYN_ARRAY(online_cpu_map, sizeof(unsigned long), cpumask_size,
PAGE_SIZE, NULL);

or something like that.

YH

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Rusty Russell wrote:
> 
> Your workaround is very random, and that scares me.  I think a huge number of 
> CPUs needs a real solution (an actual cpumask allocator, then do something 
> clever if we come across an actual fastpath).

The thing is, the inlining thing is a separate issue.

Yes, the cpumasks were what made stack pressure so critical to begin with, 
but no, a 400-byte stack frame in a deep callchain isn't acceptable 
_regardless_ of any cpumask_t issues.

Gcc inlining is a total and utter pile of shit. And _that_ is the problem. 
I seriously think we shouldn't allow gcc to inline anything at all unless 
we tell it to. That's how it used to work, and quite frankly, that's how 
it _should_ work.

The downsides of inlining are big enough from both a debugging and a real 
code generation angle (eg stack usage like this), that the upsides 
(_somesimes_ smaller kernel, possibly slightly faster code) simply aren't 
relevant.

So the "noinline" was random, yes, but this is a real issue. Looking at 
checkstack output for a saner config (NR_CPUS=16), the top entries for me 
are things like

	ide_generic_init [vmlinux]:             1384
	idefloppy_ioctl [vmlinux]:              1208
	e1000_check_options [vmlinux]:  	1152
	...

which are "leaf" functions. They are broken as hell (the e1000 is 
apparently because it builds structs on the stack that should all be 
"static const", for example), but they are different from something like 
the module init sequence in that they are not going to affect anything 
else.

It would be interesting to see what "-fno-default-inline" does to the 
kernel. It really would get rid of a _lot_ of gcc version issues too. 
Inlining behavior of gcc has long been a problem for us.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 10:35:05AM -0700, Linus Torvalds wrote:
> 
> 
> On Tue, 26 Aug 2008, Rusty Russell wrote:
> > 
> > Your workaround is very random, and that scares me.  I think a huge number of 
> > CPUs needs a real solution (an actual cpumask allocator, then do something 
> > clever if we come across an actual fastpath).
> 
> The thing is, the inlining thing is a separate issue.
> 
> Yes, the cpumasks were what made stack pressure so critical to begin with, 
> but no, a 400-byte stack frame in a deep callchain isn't acceptable 
> _regardless_ of any cpumask_t issues.
> 
> Gcc inlining is a total and utter pile of shit. And _that_ is the problem. 
> I seriously think we shouldn't allow gcc to inline anything at all unless 
> we tell it to. That's how it used to work, and quite frankly, that's how 
> it _should_ work.
> 
> The downsides of inlining are big enough from both a debugging and a real 
> code generation angle (eg stack usage like this), that the upsides 
> (_somesimes_ smaller kernel, possibly slightly faster code) simply aren't 
> relevant.
>...
> It would be interesting to see what "-fno-default-inline" does to the 
> kernel. It really would get rid of a _lot_ of gcc version issues too. 
> Inlining behavior of gcc has long been a problem for us.

I added "-fno-inline-functions-called-once -fno-early-inlining" to 
KBUILD_CFLAGS, and (with gcc 4.3) that increased the size of my kernel 
image by 2%.

And when David's "-fwhole-program --combine" will become ready the cost
of disallowing gcc to inline functions will most likely increase.

A debugging option (for better traces) to disallow gcc some inlining 
might make sense (and might even make sense for distributions to 
enable in their kernels), but when you go to use cases that require
really small kernels the cost is too high.

But if you don't trust gcc's inlining you should revert
commit 3f9b5cc018566ad9562df0648395649aebdbc5e0 that increases gcc's 
freedom regarding what to inline in 2.6.27 - what gcc 4.2 does in the 
case of the regression tracked as Bugzilla #11276 is really not funny 
(two callers -> function not inlined; gcc seems to emit the function 
although both callers later get removed (or at least should be removed) 
by dead code elimination).

> 			Linus

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Adrian Bunk wrote:
> 
> A debugging option (for better traces) to disallow gcc some inlining 
> might make sense (and might even make sense for distributions to 
> enable in their kernels), but when you go to use cases that require
> really small kernels the cost is too high.

You ignore the fact that it's really not just about debugging.

Inlining really isn't the great tool some people think it is. Especially 
not since gcc stack allocation is so horrid that it won't re-use stack 
slots etc (which I don't disagree with per se - it's _hard_ to re-use 
stack slots while still allowing code scheduling).

NOTE! I also would never claim that _our_ choices of "inline" are all that 
great, and we've often inlined too much or not inlined things that really 
could be inlined. But at least when a developer says "inline" (or forgets 
to say it), we have somebody to blame. When the compiler does insane 
things that doesn't suit us, we're just screwed.

> But if you don't trust gcc's inlining you should revert
> commit 3f9b5cc018566ad9562df0648395649aebdbc5e0 that increases gcc's 
> freedom regarding what to inline in 2.6.27

Actually, that just allows gcc to _not_ inline. Which is probably ok.

(Well, it would be ok if gcc did it well enough, it obviously has some 
problems at times).

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Adrian Bunk wrote:
> 
> I added "-fno-inline-functions-called-once -fno-early-inlining" to 
> KBUILD_CFLAGS, and (with gcc 4.3) that increased the size of my kernel 
> image by 2%.

Btw, did you check with just "-fno-inline-functions-called-once"?

The -fearly-inlining decisions _should_ be mostly right. If gcc sees early 
that a function is so small (even without any constant propagation etc) 
that it can be inlined, it's probably right. 

The inline-functions-called-once thing is what causes even big functions 
to be inlined, and that's where you find the big downsides too (eg the 
stack usage).

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Linus Torvalds wrote:
> 
> On Mon, 25 Aug 2008, Linus Torvalds wrote:
>> checkstack.pl shows these things as the top problems:
>>
>> 	0xffffffff80266234 smp_call_function_mask [vmlinux]:    2736
>> 	0xffffffff80234747 __build_sched_domains [vmlinux]:     2232
>> 	0xffffffff8023523f __build_sched_domains [vmlinux]:     2232
>>
>> Anyway, the reason smp_call_function_mask and friends have such _huge_ 
>> stack usages for you is that they contain a 'cpumask_t' on the stack.
> 
> In fact, they contain multiple CPU-masks, each 4k-bits - 512 bytes - in 
> size. And they tend to call each other.
> 
> Quite frankly, I don't think we were really ready for 4k CPU's. I'm going 
> to commit this patch to make sure others don't do that many CPU's by 
> mistake. It marks MAXCPU's as being 'broken' so you cannot select it, and 
> also limits the number of CPU's that you _can_ select to "just" 512.
> 
> Right now, 4k cpu's is known broken because of the stack usage. I'm not 
> willing to debug more of these kinds of stack smashers, they're really 
> nasty to work with. I wonder how many other random failures these have 
> been involved with?
> 
> This patch also makes the ifdef mess in Kconfig much cleaner and avoids 
> duplicate definitions by just conditionally suppressing the question and 
> giving higher defaults. 
> 
> We can enable MAXSMP and raise the CPU limits some time in the future. But 
> that future is not going to be before 2.6.27 - the code simply isn't ready 
> for it.
> 
> The reason I picked 512 CPU's as the limit is that we _used_ to limit 
> things to 255. So it's higher than it used to be, but low enough to still 
> feel safe. Considering that a 4k-bit CPU mask (512 bytes) _almost_ worked, 
> the 512-bit (64 bytes) masks are almost certainly fine.
> 
> Still, sane people should limit their NR_CPUS to 8 or 16 or something like 
> that. Very very few people really need the pain of big NR_CPUS. Not even 
> "just" 512 CPU's.
> 
> Travis, Ingo and Thomas cc'd, since they were involved in the original 
> commit (1184dc2ffe2c8fb9afb766d870850f2c3165ef25) that raised the limit.
> 
> 		Linus

Hi Linus,

[Sorry for the long winded response, but I felt that sufficient background
is needed to address this issue.... YOMV :-)]

The need to allow distros to set NR_CPUS=4096 (and NODES_SHIFT=9) is
critical to our upcoming SGI systems using what we have been calling
"UV".  This system will be capable of supporting 4096 cpu threads in a
single system image (and 16k cpus/2k nodes is right around the corner).
While obviously I cannot divulge too many details, it's sufficient to
say there are customers who not only require this extended capability,
but are extremely excited about it.

But the nature of some of these system environments is that they will
not accept a specially built kernel, but only a kernel that has been
built and certified (both from the application standpoint as well as
the security standpoint) by standard distributions.  And you probably
know how extensively these distributions test and certify for many known
defects and absolutely require that incoming source changes come from
the community supported source bases, primarily yours.

Due to the lead time required to accomplish these certifications,
the version of the distributions that will be available when this
system releases will be based on 2.6.27.  (They will allow patches
"post-2.6.27-rc.final" as long as those are committed in the source base.)
The two distributions that SGI supports for our customers is SLES
(SUSE Linux Enterprise Server) and RHEL (Red Hat Enterprise Linux).
[They, of course, are free to run any OS of their choosing, but SGI only
provides front line support for those two.]

I started last August to begin analyzing how to accomplish the above goals
and where exactly are the hot spots in the kernel that would require
attention.  It quickly became clear that cpumask_t and nodemask_t are
two variables that are very casually used (along with NR_CPUS), because
the assumption was that 64 "was more than sufficient" for an upper limit
and even extending it to 128 or 255 (254 was the maximum IPI broadcast
ID until x2apic), only added a few more bytes here and there.

I chose not to introduce too many dramatic changes and instead analyzed
every instance where cpumask_t and NR_CPUS was being used (along with the
node counterparts.)  An initial proposal was to allow the default stack
size to be increased, but this was met with a lot of objections because
of the extensive work that was done to bring it to it's current size.

So in summary, the goals of the changes that I have been making since
last October are:

	1. Allow a "typical distro" configured kernel with NR_CPUS=4096
	   and NODES_SHIFT=9 to be booted on an x86_64 system with 2GB
	   of memory.  (Some thought was given to use a 512Mb laptop
	   as the base, but because of other memory bloat from using a
	   64-bit kernel, that was considered not very useful.)

	   [Note I frequently use an allyes and allmod config for
	   testing.]

	2. To lessen as much as possible, the impact on memory usage for
	   that same kernel on that same system.

	3. To lessen as much as possible, the impact on system performance
	   for that same kernel on that same system.  [Which mostly
	   depended on #2.]

I booted the first 4096 cpu kernel last February, and since around March
or April, Ingo has been (build and boot) testing the x86 branch using
"MAXSMP" to trigger the increased defaults quite extensively (IIRC, it
was somewhere between 75% and 90% of all kernels built.)  We here at SGI
nightly build 4 trees (linux-2.6, linux-next, linux-mm, linux-x86) to
insure new checkins don't conflict with changes we've made in the past.
Unfortunately, our run testing wasn't sufficient to catch this latest
error (and I will be quickly fixing that.)

I will also revisit all the past areas to analyze if there have been
other abuses of stack and memory space added since the 4k cpu limit
was "certified" as usable and releasable.  (See below for an initial
survey of size increases between a 512cpu/64node configuration and a
4096cpu/512node configuration.)

So perhaps "MAXSMP" is not needed (or perhaps should be more hidden to
reduce accidental uses), but allowing the defaults listed above to be in
the standard x86/Kconfig insures that the distros can at least attempt
certification with the maximally configured kernels for their enterprise
editions of Linux.

There are many more changes that will be proposed for the 2.6.28 window.
Most certainly your concerns, as well as others, about how to change the
current "cpumask paradigm" to be more easily manageable for systems with
huge cpu counts, will be visited.  (And surely be well discussed. :-)

Thanks,
Mike
---

linux-2.6: v2.6.27-rc4-176-gb8e6c91

====== Data (-l 500)
... files 2 vars 1421 all 0 lim 500 unch 0

    1 - 512-64-allmodconfig
    2 - 4096-512-allmodconfig

      .1.       .2.    ..final..
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====== Sections (-l 500)
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    1 - 512-64-allmodconfig
    2 - 4096-512-allmodconfig

       .1.        .2.    ..final..
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====== Stack (-l 500)
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    2 - 4096-512-allmodconfig

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====== MemInfo ()
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(runtime meminfo not collected.)

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jamie Lokier]

Linus Torvalds wrote:
> The inline-functions-called-once thing is what causes even big functions 
> to be inlined, and that's where you find the big downsides too (eg the 
> stack usage).

That's a bit bizarre, though, isn't it?

A function which is only called from one place should, if everything
made sense, _never_ use more stack through being inlined.  Inlining
should just increase the opportunities that the called function's
local variables can share the same stack slots are the caller's dead
locals.

Whereas not inlining guarantees they occupy separate, immediately
adjacent regions of the stack, and shouldn't be increasing the total
numbers of local variables.

-- Jamie

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Ingo Molnar wrote:
> * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> 
>> On Mon, 25 Aug 2008, Linus Torvalds wrote:
>>> checkstack.pl shows these things as the top problems:
>>>
>>> 	0xffffffff80266234 smp_call_function_mask [vmlinux]:    2736
>>> 	0xffffffff80234747 __build_sched_domains [vmlinux]:     2232
>>> 	0xffffffff8023523f __build_sched_domains [vmlinux]:     2232
>>>
>>> Anyway, the reason smp_call_function_mask and friends have such _huge_ 
>>> stack usages for you is that they contain a 'cpumask_t' on the stack.
>> In fact, they contain multiple CPU-masks, each 4k-bits - 512 bytes - in 
>> size. And they tend to call each other.
>>
>> Quite frankly, I don't think we were really ready for 4k CPU's. I'm 
>> going to commit this patch to make sure others don't do that many 
>> CPU's by mistake. It marks MAXCPU's as being 'broken' so you cannot 
>> select it, and also limits the number of CPU's that you _can_ select 
>> to "just" 512.
> 
> yeah, that's OK i guess - distros can still enable 4K support if they 
> wish to. Someone interested in improving the stack footprint situation 
> should dust off the max-stack-footprint tracer so that we can catch 
> these things in a more structured way.
> 
> And i guess the next generation of 4K CPUs support should just get away 
> from cpumask_t-on-kernel-stack model altogether, as the current model is 
> not maintainable. We tried the on-kernel-stack variant, and it really 
> does not work reliably. We can fix this in v2.6.28.
> 
> 	Ingo

I would be most interested in any tools to analyze call-trees and
accumulated stack usages.  My current method of using kdb is really
time consuming.

Thanks!
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

David Miller wrote:
> From: Ingo Molnar <mingo@elte.hu>
> Date: Tue, 26 Aug 2008 09:22:20 +0200
> 
>> And i guess the next generation of 4K CPUs support should just get away 
>> from cpumask_t-on-kernel-stack model altogether, as the current model is 
>> not maintainable. We tried the on-kernel-stack variant, and it really 
>> does not work reliably. We can fix this in v2.6.28.
> 
> I recently did some work on sparc64 to use cpumask pointers
> as much as possible.
> 
> The only case that didn't work was due to a limitation in
> arch interfaces for the new generic smp_call_function() code.
> It passes a cpumask_t instead of a pointer to one via
> arch_send_call_function_ipi().
> 
> But other than that, the whole sparc64 SMP stuff uses cpumask_t
> pointers only.
> 
> What it comes down to is that you have to do the "self cpu"
> and other tests in the cross-call dispatch routines themselves,
> instead of at the top-level working on cpumask_t objects.
> 
> Otherwise you have to modify cpumask_t objects and thus pluck
> them onto the stack where they take up silly amounts of space.

Yes, I had proposed either modifying, or supplementing a new
smp_call function to pass the cpumask_t as a pointer (similar
to set_cpus_allowed_ptr.)  But an ABI change such as this was
not well received at the time.

Thanks,
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Mike Travis wrote:
> 
> The need to allow distros to set NR_CPUS=4096 (and NODES_SHIFT=9) is
> critical to our upcoming SGI systems using what we have been calling
> "UV".

That's fine. You can do it. The default kernel will not, because it's 
clearly not safe.

I really don't care what you do to _your_ images. But I will not 
distribute a known-broken kernel, and I will not debug random stack 
overflows that happen in it.

If you want the default kernel to support 4k cores, we'll need to fix the 
stack usage.  I don't think that is impossible, but IT IS NOT GOING TO 
HAPPEN for 2.6.27.

And quite frankly, if some vendor like RedHat enables NR_CPUS=4096 by 
default, they are totally and utterly crazy.

But some SGI-specific binary that is meant for SGI machines only, and has 
been extensively tested with the setup used on SGI machines is a different 
thing.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Ingo Molnar wrote:
> * David Miller <davem@davemloft.net> wrote:
> 
>> From: Ingo Molnar <mingo@elte.hu>
>> Date: Tue, 26 Aug 2008 09:22:20 +0200
>>
>>> And i guess the next generation of 4K CPUs support should just get away 
>>> from cpumask_t-on-kernel-stack model altogether, as the current model is 
>>> not maintainable. We tried the on-kernel-stack variant, and it really 
>>> does not work reliably. We can fix this in v2.6.28.
>> I recenetly did some work on sparc64 to use cpumask pointers as much 
>> as possible.
>>
>> The only case that didn't work was due to a limitation in arch 
>> interfaces for the new generic smp_call_function() code. It passes a 
>> cpumask_t instead of a pointer to one via 
>> arch_send_call_function_ipi().
>>
>> But other than that, the whole sparc64 SMP stuff uses cpumask_t 
>> pointers only.
> 
> nice!
> 
>> What it comes down to is that you have to do the "self cpu" and other 
>> tests in the cross-call dispatch routines themselves, instead of at 
>> the top-level working on cpumask_t objects.
>>
>> Otherwise you have to modify cpumask_t objects and thus pluck them 
>> onto the stack where they take up silly amounts of space.
> 
> What we did was this: we added MAXSMP which just revs up all the SMP 
> tunables to the maximum, so that we can see any problems early in 
> testing.
> 
> And we triggered problems, and we fixed a couple of regressions all 
> around stack footprint. But we didnt catch all of them - some were gcc 
> version dependent and configuration dependent. So i think it's safe to 
> say that the whole concept of allowing such a large cpumask_t to be on 
> the stack is fragile.

Iirc, it was the problem of basing percpu variables at zero that hit
problems with various gcc toolset versions.  I don't remember any
version problems with cpumask's on the stack, they all failed the
same way... :-)
> 
> Hence, i think the best way forward is to change the whole cpumask_t 
> concept and disallow explicit masks altogether. It's so easy to smack a 
> cpumask_t variable on the stack and nothing really warns about it, and 
> any function can become part of a nested call sequence.

This is a great idea!
> 
> So i think the dynamics of it has to be changed: we need a get/put API 
> and we need to make on-stack cpumask illegal on the build level (in 
> generic code at least). This has been Rusty's main argument early on i 
> think, and i now concur.
> 
> 	Ingo

Removing cpumask_t's from the stack is fairly straight forward.  The
problem of changing all functions to expect a cpumask pointer via a
global change is much more problematic.  And of course all those
functions that return a cpumask value would need to be addressed.

Thanks,
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Jamie Lokier wrote:
> 
> A function which is only called from one place should, if everything
> made sense, _never_ use more stack through being inlined.

But that's simply not true.

See the whole discussion.

The problem is that if you inline that function, the stack usage of the 
newly inlined function is now added to ALL THE OTHER paths too!

So the case we had in module loading was that yes, we had a function with 
a big stack footprint, but it was NOT in the deep path.

But by inlining it, it now moved the stack footprint "up" one level to 
another function, and now the big stack footprint really _was_ in the deep 
path, because the caller was involved in a much deeper chain. 

So inlining moves the code up the callchain, and that is a problem for the 
backtrace, but that's "just" a debugging issue. But it also moves the 
stack footprint up the callchain, and that can actually be a correctness 
issue.

Of course, a compiler doesn't _have_ to do that. A compiler _could_ have 
multiple different stack footprints for a single function, and do liveness 
analysis etc. But no sane compiler probably does that, because it's very 
painful indeed, and it's not even an issue if you aren't stack-limited 
(and being stack-limited is really just a kernel thing).

(Yeah, it can be an issue even if you have a big stack, in that you get 
worse cache behaviour, so a dense stack footprint _would_ help. But the 
complexity of stack liveness analysis is almost certainly not worth the 
relatively small gains it would get on some odd cases).

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Dave Jones]

On Tue, Aug 26, 2008 at 12:09:46PM -0700, Linus Torvalds wrote:

 > If you want the default kernel to support 4k cores, we'll need to fix the 
 > stack usage.  I don't think that is impossible, but IT IS NOT GOING TO 
 > HAPPEN for 2.6.27.
 > 
 > And quite frankly, if some vendor like RedHat enables NR_CPUS=4096 by 
 > default, they are totally and utterly crazy.

heh.  *picks through Fedora changelog*

* Thu Aug 14 2008 Dave Jones <davej@redhat.com>
- Bump max cpus supported on x86-64 to 4096. Just to see what happens.

I never did get to find out unfortunatly, because of the security fiasco
in Fedora infrastructure the last week or two.
 
 > But some SGI-specific binary that is meant for SGI machines only, and has 
 > been extensively tested with the setup used on SGI machines is a different 
 > thing.

Every extra kernel image a distro vendor ends up shipping has an associated cost.

* build time: It currently takes about 2 hours for a set of Fedora RPMs.
  For RHEL it'll be even worse due to the extra archs).
  Killing off -smp specific builds was a big win for us in this regard.
  Adding extra flavours is always painful.

* diskspace (distro kernels aren't small. With the associated debugging symbols,
   they take up a shitload of disk space really fast).

* Having everyone running the same kernel makes it much easier to test/debug.
  Our QA guys hate adding extra columns to their test matrix.

But yes, for this to be even remotely feasible, there has to be a negligable
performance cost associated with it, which right now, we clearly don't have.
Given that the number of people running 4096 CPU boxes even in a few years time
will still be tiny, punishing the common case is obviously absurd.

	Dave

-- 
http://www.codemonkey.org.uk

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Linus Torvalds wrote:
> 
> On Tue, 26 Aug 2008, Mike Travis wrote:
>> The need to allow distros to set NR_CPUS=4096 (and NODES_SHIFT=9) is
>> critical to our upcoming SGI systems using what we have been calling
>> "UV".
> 
> That's fine. You can do it. The default kernel will not, because it's 
> clearly not safe.
> 
> I really don't care what you do to _your_ images. But I will not 
> distribute a known-broken kernel, and I will not debug random stack 
> overflows that happen in it.
> 
> If you want the default kernel to support 4k cores, we'll need to fix the 
> stack usage.  I don't think that is impossible, but IT IS NOT GOING TO 
> HAPPEN for 2.6.27.
> 
> And quite frankly, if some vendor like RedHat enables NR_CPUS=4096 by 
> default, they are totally and utterly crazy.
> 
> But some SGI-specific binary that is meant for SGI machines only, and has 
> been extensively tested with the setup used on SGI machines is a different 
> thing.
> 
> 			Linus

Ok, thanks for the reply, and looking into this issue.  We will "strongly
encourage" our distros to base the relevant releases on 2.6.28. :-)  

[Supplying an SGI-specific kernel would not be acceptable to many of our
customers because of the certification issues I mentioned.] 

Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Mike Travis wrote:
> 
> I would be most interested in any tools to analyze call-trees and
> accumulated stack usages.  My current method of using kdb is really
> time consuming.

Well, even just scripts/checkstack.pl is quite relevant.

The fact is, anything with a stack footprint of more than a hundred bytes 
is suspect. We _do_ have a lot of cases of several hundred bytes, and some 
of them are even very intentional.

For an example of _intentional_ and valid large stacks, look at 
do_sys_poll and do_select. They both have a big stack footprint in a 
normal kernel, and that's on purpose - it's not pretty, but they are very 
common and performance-sensitive functions, and using a big stack allows 
some basic allocations to be much cheaper by default.

Same goes for early_printk(), although I don't think the reasons are 
really very strong in that case.

Sadly, while those functions are _fairly_ high up, they aren't at the top, 
and we do have a lot of other functions that have huge stack footprints 
for totally bogus reasons. But the intentional ones are at least in the 
top ten.

But the kernel that Alan had problems with was different. The 
_intentional_ ones were way down in the noise.  do_sys_poll wasn't in the 
top ten, it was barely even in the top 50! (It was in fact #49, to be 
exact).

So look at the top ten in my kernel:

     1  ide_generic_init [vmlinux]:             1384
     2  idefloppy_ioctl [vmlinux]:              1208
     3  e1000_check_options [vmlinux]:  	1152
     4  do_sys_poll [vmlinux]:          	904
     5  ide_floppy_get_capacity [vmlinux]:      872
     6  do_select [vmlinux]:                    744
     7  early_printk [vmlinux]:         	720
     8  do_task_stat [vmlinux]:         	680
     9  mmc_ioctl [vmlinux]:                    648
    10  elf_kcore_store_hdr [vmlinux]:  	576

.. and in Alan's kernel:

     1  smp_call_function_mask [vmlinux]:       2736
     2  __build_sched_domains [vmlinux]:        2232
     3  setup_IO_APIC_irq [vmlinux]:            1616
     4  arch_setup_ht_irq [vmlinux]:            1600
     5  arch_setup_msi_irq [vmlinux]:   	1600
     6  __assign_irq_vector [vmlinux]:  	1592
     7  move_task_off_dead_cpu [vmlinux]:       1592
     8  tick_handle_oneshot_broadcast [vmlinux]:1544
     9  store_scaling_governor [vmlinux]:       1376
    10  cpuset_write_resmask [vmlinux]:		1360

That's a big difference. The top #1 in my kernel would just _barely_ be in 
the top 10 in Alan's kernel (he doesn't have it at all, because he didn't 
compile the drives I did into the kernel).

And the top three in my kernel are just because of crap code. That 
"e1000_check_options" thing is there just because it creates multiple 
"struct e1000_option" structures. I wrote an ugly but totally trivial 
patch to get it down to ~600 bytes, and it would be less if I had bothered 
to waste any more time on it.

The others are similar issues of "people just didn't think".

But look at the top ones in Alan's kernel. Not only are they _much_ bigger 
than the top ones in a sane kernel, they are _all_ due to cpumask_t, I 
think.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Ingo Molnar wrote:
> * Christoph Lameter <cl@linux-foundation.org> wrote:
> 
>> Alan D. Brunelle wrote:
>>
>>> I think you're right: the kernel as a whole may not be ready for 4,096
>>> CPUs apparently...
>> Mike has been working diligently on getting all these cpumasks off the 
>> stack for the last months and has created an infrastructure to do 
>> this. So I think we are close. It might just be a matter of merging 
>> some more patches that are still left in Ingo's tree.
> 
> hm, there are no such patches left that i know of - the only bits in 
> -tip are the zero-based percpu, which was found to be a bit fragile in 
> testing:

Yes, it's just a case of new changes abusing the stack.
> 
>  earth4:~/tip> git-log-line --author=Travis linus..
>  d379497: Zero based percpu: infrastructure to rebase the per cpu area to zero
>  b3a0cb4: x86: extend percpu ops to 64 bit
> 
> [and it has no relevance to stack footprint.]
> 
> So i dont think the current cpumask_t approach will work. We simply 
> should not get into an endless fight against the windmills that 
> introduce on-stack cpumask_t again and again. We should just take the 
> plunge once and do a clean alloc/free cpumask model. Most of the hotpath 
> cpumasks are constant or pre-constructed, so they are not a real issue.

It would have been nice to know this 9 months ago... ;-)
> 
> Plus, on the general question of stack footprint problems and the 
> difficulty of debugging them, the worst-case stack footprint tracer i 
> wrote for -rt some time ago should be dusted off as well and put into 
> ftrace. David has something quite close to that for Sparc64 already.
> 
> 	Ingo

I'll start experimenting with globally changing cpumask_t to be a pointer,
and see what falls out.

Thanks,
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jeff Garzik]

Linus Torvalds wrote:
> The downsides of inlining are big enough from both a debugging and a real 
> code generation angle (eg stack usage like this), that the upsides 
> (_somesimes_ smaller kernel, possibly slightly faster code) simply aren't 
> relevant.
> 
> So the "noinline" was random, yes, but this is a real issue. Looking at 
> checkstack output for a saner config (NR_CPUS=16), the top entries for me 
> are things like
> 
> 	ide_generic_init [vmlinux]:             1384
> 	idefloppy_ioctl [vmlinux]:              1208
> 	e1000_check_options [vmlinux]:  	1152
> 	...
> 
> which are "leaf" functions. They are broken as hell (the e1000 is 
> apparently because it builds structs on the stack that should all be 
> "static const", for example), but they are different from something like 
> the module init sequence in that they are not going to affect anything 
> else.


e1000_check_options builds a struct (singular) on the stack, really... 
struct e1000_option is reasonably small.

The problem, which has also shown itself in large ioctl-style switch{} 
statements, is that gcc will generate code such that the stack usage 
from independent code branches

	if {cond1} {
		char buster1[1000];
		foo(buster1);
	} else if (cond2) {
		char buster2[1000];
		foo(buster2);
	}

are added together, not noticed as mutually exclusive.

Of course, adding 'static const' as you noted is a reasonable 
workaround, but gcc is really annoying WRT stack allocation in this manner.

I had problems in the past, before struct ethtool_ops, with like ethtool 
ioctl switch statements using gobs of stack.  In fact, that was a big 
motivation for struct ethtool_ops.

	Jeff

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Dave Jones wrote:
...
> 
> But yes, for this to be even remotely feasible, there has to be a negligable
> performance cost associated with it, which right now, we clearly don't have.
> Given that the number of people running 4096 CPU boxes even in a few years time
> will still be tiny, punishing the common case is obviously absurd.
> 
> 	Dave
> 

I did do some fairly extensive benchmarking between configs of NR_CPUS = 128 and
4096 and most performance hits were in the neighborhood of < 5% on systems with
8 cpus and 4GB of memory (our most common test system).  [But changing cpumask_t's
to be pointers instead of values will likely increase this.]  I've tried to be
very sensitive to this issue with all my previous changes, so convincing the distros
to set NR_CPUS=4096 would be as painless for them as possible. ;-)

Btw, huge count cpu systems I don't think are that far away.  I believe the nextgen
Larabbee chips will be geared towards HPC applications [instead of just GFX apps],
and putting 4 of these chips on a motherboard would add up to 512 cpu threads (1024
if they support hyperthreading.)

Thanks,
Mike

e1000 horridness (was Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected)

[Linus Torvalds]

On Tue, 26 Aug 2008, Jeff Garzik wrote:
> 
> e1000_check_options builds a struct (singular) on the stack, really... struct
> e1000_option is reasonably small.

No it doesn't.

Look a bit more closely.

It builds a struct (singular) MANY MANY times. It also then builds up a 
huge e1000_opt_list[] array, even though it is const and should be static 
(and const).

I know. I wrote a patch to FIX it.

Here's the patch. It shrinks the stack from 1152 bytes to 192 bytes (the 
first version, that only did the e1000_option part, got it down to 600 
bytes). About half comes from not using multiple "e1000_option" 
structures, the other half comes from turning the "e1000_opt_list[]" 
arrays into "static const" instead, so that gcc doesn't copy them onto the 
stack.

Most of the patch is actually doing things like turning

	struct struct e1000_option opt = {

(which declares a _new_ e1000_option variable each time) into

	opt = (struct e1000_option) {

which just re-uses the single variable.

It becomes slightly larger than that, because some places the "opt = .." 
had to be moved around, since it's no longer a variable declaration, but a 
regular assignment.

The rest is just adding "const" to the right places, and turning

	struct e1000_opt_list speed_list[] = ..

into

	static const struct e1000_opt_list speed_list[] = ..

instead, and fixing the indentation to be more straightforward.

I have not tested the dang thing, but I think it's correct. And it turns 
stack usage from "totally horrible and broken" into "pretty reasonable".

		Linus

---
 drivers/net/e1000/e1000_param.c |   81 +++++++++++++++++++++-----------------
 1 files changed, 45 insertions(+), 36 deletions(-)

diff --git a/drivers/net/e1000/e1000_param.c b/drivers/net/e1000/e1000_param.c
index b9f90a5..213437d 100644
--- a/drivers/net/e1000/e1000_param.c
+++ b/drivers/net/e1000/e1000_param.c
@@ -208,7 +208,7 @@ struct e1000_option {
 		} r;
 		struct { /* list_option info */
 			int nr;
-			struct e1000_opt_list { int i; char *str; } *p;
+			const struct e1000_opt_list { int i; char *str; } *p;
 		} l;
 	} arg;
 };
@@ -242,7 +242,7 @@ static int __devinit e1000_validate_option(unsigned int *value,
 		break;
 	case list_option: {
 		int i;
-		struct e1000_opt_list *ent;
+		const struct e1000_opt_list *ent;
 
 		for (i = 0; i < opt->arg.l.nr; i++) {
 			ent = &opt->arg.l.p[i];
@@ -279,7 +279,9 @@ static void e1000_check_copper_options(struct e1000_adapter *adapter);
 
 void __devinit e1000_check_options(struct e1000_adapter *adapter)
 {
+	struct e1000_option opt;
 	int bd = adapter->bd_number;
+
 	if (bd >= E1000_MAX_NIC) {
 		DPRINTK(PROBE, NOTICE,
 		       "Warning: no configuration for board #%i\n", bd);
@@ -287,19 +289,21 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 	}
 
 	{ /* Transmit Descriptor Count */
-		struct e1000_option opt = {
+		struct e1000_tx_ring *tx_ring = adapter->tx_ring;
+		int i;
+		e1000_mac_type mac_type = adapter->hw.mac_type;
+
+		opt = (struct e1000_option) {
 			.type = range_option,
 			.name = "Transmit Descriptors",
 			.err  = "using default of "
 				__MODULE_STRING(E1000_DEFAULT_TXD),
 			.def  = E1000_DEFAULT_TXD,
-			.arg  = { .r = { .min = E1000_MIN_TXD }}
+			.arg  = { .r = {
+				.min = E1000_MIN_TXD,
+				.max = mac_type < e1000_82544 ? E1000_MAX_TXD : E1000_MAX_82544_TXD
+				}}
 		};
-		struct e1000_tx_ring *tx_ring = adapter->tx_ring;
-		int i;
-		e1000_mac_type mac_type = adapter->hw.mac_type;
-		opt.arg.r.max = mac_type < e1000_82544 ?
-			E1000_MAX_TXD : E1000_MAX_82544_TXD;
 
 		if (num_TxDescriptors > bd) {
 			tx_ring->count = TxDescriptors[bd];
@@ -313,19 +317,21 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 			tx_ring[i].count = tx_ring->count;
 	}
 	{ /* Receive Descriptor Count */
-		struct e1000_option opt = {
+		struct e1000_rx_ring *rx_ring = adapter->rx_ring;
+		int i;
+		e1000_mac_type mac_type = adapter->hw.mac_type;
+
+		opt = (struct e1000_option) {
 			.type = range_option,
 			.name = "Receive Descriptors",
 			.err  = "using default of "
 				__MODULE_STRING(E1000_DEFAULT_RXD),
 			.def  = E1000_DEFAULT_RXD,
-			.arg  = { .r = { .min = E1000_MIN_RXD }}
+			.arg  = { .r = {
+				.min = E1000_MIN_RXD,
+				.max = mac_type < e1000_82544 ? E1000_MAX_RXD : E1000_MAX_82544_RXD
+			}}
 		};
-		struct e1000_rx_ring *rx_ring = adapter->rx_ring;
-		int i;
-		e1000_mac_type mac_type = adapter->hw.mac_type;
-		opt.arg.r.max = mac_type < e1000_82544 ? E1000_MAX_RXD :
-			E1000_MAX_82544_RXD;
 
 		if (num_RxDescriptors > bd) {
 			rx_ring->count = RxDescriptors[bd];
@@ -339,7 +345,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 			rx_ring[i].count = rx_ring->count;
 	}
 	{ /* Checksum Offload Enable/Disable */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = enable_option,
 			.name = "Checksum Offload",
 			.err  = "defaulting to Enabled",
@@ -363,7 +369,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 			 { E1000_FC_FULL,    "Flow Control Enabled" },
 			 { E1000_FC_DEFAULT, "Flow Control Hardware Default" }};
 
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = list_option,
 			.name = "Flow Control",
 			.err  = "reading default settings from EEPROM",
@@ -381,7 +387,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Transmit Interrupt Delay */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = range_option,
 			.name = "Transmit Interrupt Delay",
 			.err  = "using default of " __MODULE_STRING(DEFAULT_TIDV),
@@ -399,7 +405,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Transmit Absolute Interrupt Delay */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = range_option,
 			.name = "Transmit Absolute Interrupt Delay",
 			.err  = "using default of " __MODULE_STRING(DEFAULT_TADV),
@@ -417,7 +423,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Receive Interrupt Delay */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = range_option,
 			.name = "Receive Interrupt Delay",
 			.err  = "using default of " __MODULE_STRING(DEFAULT_RDTR),
@@ -435,7 +441,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Receive Absolute Interrupt Delay */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = range_option,
 			.name = "Receive Absolute Interrupt Delay",
 			.err  = "using default of " __MODULE_STRING(DEFAULT_RADV),
@@ -453,7 +459,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Interrupt Throttling Rate */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = range_option,
 			.name = "Interrupt Throttling Rate (ints/sec)",
 			.err  = "using default of " __MODULE_STRING(DEFAULT_ITR),
@@ -497,7 +503,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Smart Power Down */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = enable_option,
 			.name = "PHY Smart Power Down",
 			.err  = "defaulting to Disabled",
@@ -513,7 +519,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Kumeran Lock Loss Workaround */
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = enable_option,
 			.name = "Kumeran Lock Loss Workaround",
 			.err  = "defaulting to Enabled",
@@ -578,16 +584,18 @@ static void __devinit e1000_check_fiber_options(struct e1000_adapter *adapter)
 
 static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
 {
+	struct e1000_option opt;
 	unsigned int speed, dplx, an;
 	int bd = adapter->bd_number;
 
 	{ /* Speed */
-		struct e1000_opt_list speed_list[] = {{          0, "" },
-						      {   SPEED_10, "" },
-						      {  SPEED_100, "" },
-						      { SPEED_1000, "" }};
+		static const struct e1000_opt_list speed_list[] = {
+			{          0, "" },
+			{   SPEED_10, "" },
+			{  SPEED_100, "" },
+			{ SPEED_1000, "" }};
 
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = list_option,
 			.name = "Speed",
 			.err  = "parameter ignored",
@@ -604,11 +612,12 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
 		}
 	}
 	{ /* Duplex */
-		struct e1000_opt_list dplx_list[] = {{           0, "" },
-						     { HALF_DUPLEX, "" },
-						     { FULL_DUPLEX, "" }};
+		static const struct e1000_opt_list dplx_list[] = {
+			{           0, "" },
+			{ HALF_DUPLEX, "" },
+			{ FULL_DUPLEX, "" }};
 
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = list_option,
 			.name = "Duplex",
 			.err  = "parameter ignored",
@@ -637,7 +646,7 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
 		       "parameter ignored\n");
 		adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
 	} else { /* Autoneg */
-		struct e1000_opt_list an_list[] =
+		static const struct e1000_opt_list an_list[] =
 			#define AA "AutoNeg advertising "
 			{{ 0x01, AA "10/HD" },
 			 { 0x02, AA "10/FD" },
@@ -671,7 +680,7 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
 			 { 0x2e, AA "1000/FD, 100/FD, 100/HD, 10/FD" },
 			 { 0x2f, AA "1000/FD, 100/FD, 100/HD, 10/FD, 10/HD" }};
 
-		struct e1000_option opt = {
+		opt = (struct e1000_option) {
 			.type = list_option,
 			.name = "AutoNeg",
 			.err  = "parameter ignored",

Re: e1000 horridness (was Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected)

[Kok, Auke]

Linus Torvalds wrote:
> 
> On Tue, 26 Aug 2008, Jeff Garzik wrote:
>> e1000_check_options builds a struct (singular) on the stack, really... struct
>> e1000_option is reasonably small.
> 
> No it doesn't.
> 
> Look a bit more closely.
> 
> It builds a struct (singular) MANY MANY times. It also then builds up a 
> huge e1000_opt_list[] array, even though it is const and should be static 
> (and const).
> 
> I know. I wrote a patch to FIX it.

totally cool patch afaics - if I still maintained this driver I'd have this tested
and merged right away :)

I suppose Jeff Kirsher is already doing so right now.

I suppose that he'll have to look at the other Intel ethernet drivers as well :)

Jeff, please add my:

Reveiewed-by: Auke Kok <auke-jan.h.kok@intel.com>

Cheers,

Auke

> 
> Here's the patch. It shrinks the stack from 1152 bytes to 192 bytes (the 
> first version, that only did the e1000_option part, got it down to 600 
> bytes). About half comes from not using multiple "e1000_option" 
> structures, the other half comes from turning the "e1000_opt_list[]" 
> arrays into "static const" instead, so that gcc doesn't copy them onto the 
> stack.
> 
> Most of the patch is actually doing things like turning
> 
> 	struct struct e1000_option opt = {
> 
> (which declares a _new_ e1000_option variable each time) into
> 
> 	opt = (struct e1000_option) {
> 
> which just re-uses the single variable.
> 
> It becomes slightly larger than that, because some places the "opt = .." 
> had to be moved around, since it's no longer a variable declaration, but a 
> regular assignment.
> 
> The rest is just adding "const" to the right places, and turning
> 
> 	struct e1000_opt_list speed_list[] = ..
> 
> into
> 
> 	static const struct e1000_opt_list speed_list[] = ..
> 
> instead, and fixing the indentation to be more straightforward.
> 
> I have not tested the dang thing, but I think it's correct. And it turns 
> stack usage from "totally horrible and broken" into "pretty reasonable".
> 
> 		Linus
> 
> ---
>  drivers/net/e1000/e1000_param.c |   81 +++++++++++++++++++++-----------------
>  1 files changed, 45 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/net/e1000/e1000_param.c b/drivers/net/e1000/e1000_param.c
> index b9f90a5..213437d 100644
> --- a/drivers/net/e1000/e1000_param.c
> +++ b/drivers/net/e1000/e1000_param.c
> @@ -208,7 +208,7 @@ struct e1000_option {
>  		} r;
>  		struct { /* list_option info */
>  			int nr;
> -			struct e1000_opt_list { int i; char *str; } *p;
> +			const struct e1000_opt_list { int i; char *str; } *p;
>  		} l;
>  	} arg;
>  };
> @@ -242,7 +242,7 @@ static int __devinit e1000_validate_option(unsigned int *value,
>  		break;
>  	case list_option: {
>  		int i;
> -		struct e1000_opt_list *ent;
> +		const struct e1000_opt_list *ent;
>  
>  		for (i = 0; i < opt->arg.l.nr; i++) {
>  			ent = &opt->arg.l.p[i];
> @@ -279,7 +279,9 @@ static void e1000_check_copper_options(struct e1000_adapter *adapter);
>  
>  void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  {
> +	struct e1000_option opt;
>  	int bd = adapter->bd_number;
> +
>  	if (bd >= E1000_MAX_NIC) {
>  		DPRINTK(PROBE, NOTICE,
>  		       "Warning: no configuration for board #%i\n", bd);
> @@ -287,19 +289,21 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  	}
>  
>  	{ /* Transmit Descriptor Count */
> -		struct e1000_option opt = {
> +		struct e1000_tx_ring *tx_ring = adapter->tx_ring;
> +		int i;
> +		e1000_mac_type mac_type = adapter->hw.mac_type;
> +
> +		opt = (struct e1000_option) {
>  			.type = range_option,
>  			.name = "Transmit Descriptors",
>  			.err  = "using default of "
>  				__MODULE_STRING(E1000_DEFAULT_TXD),
>  			.def  = E1000_DEFAULT_TXD,
> -			.arg  = { .r = { .min = E1000_MIN_TXD }}
> +			.arg  = { .r = {
> +				.min = E1000_MIN_TXD,
> +				.max = mac_type < e1000_82544 ? E1000_MAX_TXD : E1000_MAX_82544_TXD
> +				}}
>  		};
> -		struct e1000_tx_ring *tx_ring = adapter->tx_ring;
> -		int i;
> -		e1000_mac_type mac_type = adapter->hw.mac_type;
> -		opt.arg.r.max = mac_type < e1000_82544 ?
> -			E1000_MAX_TXD : E1000_MAX_82544_TXD;
>  
>  		if (num_TxDescriptors > bd) {
>  			tx_ring->count = TxDescriptors[bd];
> @@ -313,19 +317,21 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  			tx_ring[i].count = tx_ring->count;
>  	}
>  	{ /* Receive Descriptor Count */
> -		struct e1000_option opt = {
> +		struct e1000_rx_ring *rx_ring = adapter->rx_ring;
> +		int i;
> +		e1000_mac_type mac_type = adapter->hw.mac_type;
> +
> +		opt = (struct e1000_option) {
>  			.type = range_option,
>  			.name = "Receive Descriptors",
>  			.err  = "using default of "
>  				__MODULE_STRING(E1000_DEFAULT_RXD),
>  			.def  = E1000_DEFAULT_RXD,
> -			.arg  = { .r = { .min = E1000_MIN_RXD }}
> +			.arg  = { .r = {
> +				.min = E1000_MIN_RXD,
> +				.max = mac_type < e1000_82544 ? E1000_MAX_RXD : E1000_MAX_82544_RXD
> +			}}
>  		};
> -		struct e1000_rx_ring *rx_ring = adapter->rx_ring;
> -		int i;
> -		e1000_mac_type mac_type = adapter->hw.mac_type;
> -		opt.arg.r.max = mac_type < e1000_82544 ? E1000_MAX_RXD :
> -			E1000_MAX_82544_RXD;
>  
>  		if (num_RxDescriptors > bd) {
>  			rx_ring->count = RxDescriptors[bd];
> @@ -339,7 +345,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  			rx_ring[i].count = rx_ring->count;
>  	}
>  	{ /* Checksum Offload Enable/Disable */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = enable_option,
>  			.name = "Checksum Offload",
>  			.err  = "defaulting to Enabled",
> @@ -363,7 +369,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  			 { E1000_FC_FULL,    "Flow Control Enabled" },
>  			 { E1000_FC_DEFAULT, "Flow Control Hardware Default" }};
>  
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = list_option,
>  			.name = "Flow Control",
>  			.err  = "reading default settings from EEPROM",
> @@ -381,7 +387,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Transmit Interrupt Delay */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = range_option,
>  			.name = "Transmit Interrupt Delay",
>  			.err  = "using default of " __MODULE_STRING(DEFAULT_TIDV),
> @@ -399,7 +405,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Transmit Absolute Interrupt Delay */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = range_option,
>  			.name = "Transmit Absolute Interrupt Delay",
>  			.err  = "using default of " __MODULE_STRING(DEFAULT_TADV),
> @@ -417,7 +423,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Receive Interrupt Delay */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = range_option,
>  			.name = "Receive Interrupt Delay",
>  			.err  = "using default of " __MODULE_STRING(DEFAULT_RDTR),
> @@ -435,7 +441,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Receive Absolute Interrupt Delay */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = range_option,
>  			.name = "Receive Absolute Interrupt Delay",
>  			.err  = "using default of " __MODULE_STRING(DEFAULT_RADV),
> @@ -453,7 +459,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Interrupt Throttling Rate */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = range_option,
>  			.name = "Interrupt Throttling Rate (ints/sec)",
>  			.err  = "using default of " __MODULE_STRING(DEFAULT_ITR),
> @@ -497,7 +503,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Smart Power Down */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = enable_option,
>  			.name = "PHY Smart Power Down",
>  			.err  = "defaulting to Disabled",
> @@ -513,7 +519,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Kumeran Lock Loss Workaround */
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = enable_option,
>  			.name = "Kumeran Lock Loss Workaround",
>  			.err  = "defaulting to Enabled",
> @@ -578,16 +584,18 @@ static void __devinit e1000_check_fiber_options(struct e1000_adapter *adapter)
>  
>  static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
>  {
> +	struct e1000_option opt;
>  	unsigned int speed, dplx, an;
>  	int bd = adapter->bd_number;
>  
>  	{ /* Speed */
> -		struct e1000_opt_list speed_list[] = {{          0, "" },
> -						      {   SPEED_10, "" },
> -						      {  SPEED_100, "" },
> -						      { SPEED_1000, "" }};
> +		static const struct e1000_opt_list speed_list[] = {
> +			{          0, "" },
> +			{   SPEED_10, "" },
> +			{  SPEED_100, "" },
> +			{ SPEED_1000, "" }};
>  
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = list_option,
>  			.name = "Speed",
>  			.err  = "parameter ignored",
> @@ -604,11 +612,12 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
>  		}
>  	}
>  	{ /* Duplex */
> -		struct e1000_opt_list dplx_list[] = {{           0, "" },
> -						     { HALF_DUPLEX, "" },
> -						     { FULL_DUPLEX, "" }};
> +		static const struct e1000_opt_list dplx_list[] = {
> +			{           0, "" },
> +			{ HALF_DUPLEX, "" },
> +			{ FULL_DUPLEX, "" }};
>  
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = list_option,
>  			.name = "Duplex",
>  			.err  = "parameter ignored",
> @@ -637,7 +646,7 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
>  		       "parameter ignored\n");
>  		adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
>  	} else { /* Autoneg */
> -		struct e1000_opt_list an_list[] =
> +		static const struct e1000_opt_list an_list[] =
>  			#define AA "AutoNeg advertising "
>  			{{ 0x01, AA "10/HD" },
>  			 { 0x02, AA "10/FD" },
> @@ -671,7 +680,7 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
>  			 { 0x2e, AA "1000/FD, 100/FD, 100/HD, 10/FD" },
>  			 { 0x2f, AA "1000/FD, 100/FD, 100/HD, 10/FD, 10/HD" }};
>  
> -		struct e1000_option opt = {
> +		opt = (struct e1000_option) {
>  			.type = list_option,
>  			.name = "AutoNeg",
>  			.err  = "parameter ignored",

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 11:40:10AM -0700, Linus Torvalds wrote:
> 
> 
> On Tue, 26 Aug 2008, Adrian Bunk wrote:
> > 
> > A debugging option (for better traces) to disallow gcc some inlining 
> > might make sense (and might even make sense for distributions to 
> > enable in their kernels), but when you go to use cases that require
> > really small kernels the cost is too high.
> 
> You ignore the fact that it's really not just about debugging.

I had in mind that we anyway have to support it for tiny kernels.

I simply don't see that we add kconfig options for 5kB of code for
tiny kernels but remove something like this that can cause size
increases > 1%.

> Inlining really isn't the great tool some people think it is. Especially 
> not since gcc stack allocation is so horrid that it won't re-use stack 
> slots etc (which I don't disagree with per se - it's _hard_ to re-use 
> stack slots while still allowing code scheduling).

gcc's stack allocation has become better
(that's why we disable unit-at-a-time only for gcc 3.4 on i386).

> NOTE! I also would never claim that _our_ choices of "inline" are all that 
> great, and we've often inlined too much or not inlined things that really 
> could be inlined. But at least when a developer says "inline" (or forgets 
> to say it), we have somebody to blame. When the compiler does insane 
> things that doesn't suit us, we're just screwed.

Most LOCs of the kernel are not written by people like you or Al Viro or 
David Miller, and the average kernel developer is unlikely to do it as 
good as gcc.

For the average driver the choice is realistically between
"inline's randomly sprinkled across the driver" and
"no inline's, leave it to gcc".

And code evolves during the years from tiny with 1 caller to huge with 
many callers.

BTW:
I just ran checkstack on a (roughly) allyesconfig kernel, and we have a 
new driver that allocates "unsigned char recvbuf[1500];" on the stack...

> > But if you don't trust gcc's inlining you should revert
> > commit 3f9b5cc018566ad9562df0648395649aebdbc5e0 that increases gcc's 
> > freedom regarding what to inline in 2.6.27
> 
> Actually, that just allows gcc to _not_ inline. Which is probably ok.
> 
> (Well, it would be ok if gcc did it well enough, it obviously has some 
> problems at times).

With the "gcc inline's static functions" you complain about we have
4-5 years of experience.

Suddenly allowing 4 release series of gcc to ignore any inline's is a 
completely new area for us. I'd generally agree with giving gcc more 
freedom here, but I'd rather do it right by removing tons of wrong 
inline's than doing one global change hoping that it will make things 
better.

And whether the "optimized inlining" actually makes the kernel bigger or 
smaller depends in my experience on the .config and the gcc version.

> 			Linus

cu
Adrian

[1] there are some rare exceptions

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Adrian Bunk wrote:
> 
> I had in mind that we anyway have to support it for tiny kernels.

I actually don't think that is true.

If we really were to decide to be stricter about it, and it makes a big 
size difference, we can probably also add a tool to warn about functions 
that really should be inline.

> > Inlining really isn't the great tool some people think it is. Especially 
> > not since gcc stack allocation is so horrid that it won't re-use stack 
> > slots etc (which I don't disagree with per se - it's _hard_ to re-use 
> > stack slots while still allowing code scheduling).
> 
> gcc's stack allocation has become better
> (that's why we disable unit-at-a-time only for gcc 3.4 on i386).


I agree that it has become better. But it still absolutely *sucks*.

For example, see the patch I just posted about e1000 stack usage. Even 
though the variables were all in completely separate scopes, they all got 
individual space on the stack over the whole lifetime of the function, 
causing an explosion of stack-space. As such, gcc used 500 bytes too much 
of stack, just because it didn't re-use the stackspace.

That was with gcc-4.3.0, and no, there were hardly any inlining issues 
involevd, although it is true that inlining actually did make it slightly 
worse in that case too (but since it was essentially a leaf function, that 
had little real life impact, since there were no deep callchains below it 
to care).

So the fact is, "better" simply is not "good enough". We still need to do 
a lot of optimizations _manually_, because gcc cannot see that it can 
re-use the stack-slots.

And sometimes those "optimizations" are actually performance 
pessimizations, because in order to make gcc not use all the stack at the 
same time, you simply have to break things out and force-disable inlining.

> Most LOCs of the kernel are not written by people like you or Al Viro or 
> David Miller, and the average kernel developer is unlikely to do it as 
> good as gcc.

Sure. But we do have tools. We do have checkstack.pl, it's just that it 
hasn't been an issue in a long time, so I suspect many people didn't even 
_realize_ we have it, and I certainly can attest to the fact that even 
people who remember it - like me - don't actually tend to run it all that 
often.

> For the average driver the choice is realistically between
> "inline's randomly sprinkled across the driver" and
> "no inline's, leave it to gcc".

And neither is likely to be a big problem.

> BTW:
> I just ran checkstack on a (roughly) allyesconfig kernel, and we have a 
> new driver that allocates "unsigned char recvbuf[1500];" on the stack...

Yeah, it's _way_ too easy to do bad things.

> With the "gcc inline's static functions" you complain about we have
> 4-5 years of experience.

Sure. And most of it isn't all that great.

But I do agree that lettign gcc make more decisions is _dangerous_. 
However, in this case, at least, the decisions it makes would at least 
make for less inlining, and thus less stack space explosion.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[David Miller]

From: Mike Travis <travis@sgi.com>
Date: Tue, 26 Aug 2008 12:06:18 -0700

> David Miller wrote:
> > The only case that didn't work was due to a limitation in
> > arch interfaces for the new generic smp_call_function() code.
> > It passes a cpumask_t instead of a pointer to one via
> > arch_send_call_function_ipi().
> > 
> > But other than that, the whole sparc64 SMP stuff uses cpumask_t
> > pointers only.
> > 
> > What it comes down to is that you have to do the "self cpu"
> > and other tests in the cross-call dispatch routines themselves,
> > instead of at the top-level working on cpumask_t objects.
> > 
> > Otherwise you have to modify cpumask_t objects and thus pluck
> > them onto the stack where they take up silly amounts of space.
> 
> Yes, I had proposed either modifying, or supplementing a new
> smp_call function to pass the cpumask_t as a pointer (similar
> to set_cpus_allowed_ptr.)  But an ABI change such as this was
> not well received at the time.

What it seems to come down to is that any cpumask_t not inside of
a dynamically allocated object should be marked const.

And that is something we can enforce at compile time.

Linus has just suggested dynamically allocating cpumask_t's
for such cases but I don't see that as the fix either.

Just mark them const and enforce that cpumask_t objects can only
be modified when they appear in dynamically allocated objects.

You really don't need to modify the ones that passed around functions
anyways.  The only code that wants to change bits in these things is
the cpu cross-call dispatch stuff, and that cpu choice logic can just
live where it belongs down in the cross-call dispatch code.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 11:47:01AM -0700, Linus Torvalds wrote:
> 
> 
> On Tue, 26 Aug 2008, Adrian Bunk wrote:
> > 
> > I added "-fno-inline-functions-called-once -fno-early-inlining" to 
> > KBUILD_CFLAGS, and (with gcc 4.3) that increased the size of my kernel 
> > image by 2%.
> 
> Btw, did you check with just "-fno-inline-functions-called-once"?
> 
> The -fearly-inlining decisions _should_ be mostly right. If gcc sees early 
> that a function is so small (even without any constant propagation etc) 
> that it can be inlined, it's probably right. 
> 
> The inline-functions-called-once thing is what causes even big functions 
> to be inlined, and that's where you find the big downsides too (eg the 
> stack usage).

-fno-inline-functions-called-once alone costs me nearly 1% in code size.

And I'd expect it to become more with "-fwhole-program --combine".


If you think we have too many stacksize problems I'd suggest to consider 
removing the choice of 4k stacks on i386, sh and m68knommu instead of 
using -fno-inline-functions-called-once:

Now that 32bit x86 is no longer used for extreme highend configurations 
the only serious usecase for 4k stacks are AFAIK space savings on 
embedded archs.

4k stacks have caused us much pain [1], and the cases where gcc inlined 
too much were the easy ones.

I'm not saying that I'd like removing the choice of 4k stacks, but if we 
want to reduce the number of stack related problems that's IMHO the 
better alternative.


> 			Linus

cu
Adrian

[1] AFAIR some callpaths in the kernel are still too big

BTW: In case anyone wonders about why I suggest removing 4k stacks:
     My position is that 4k stacks should either be enabled 
     unconditionally or no longer offered at all.
     And if we remove 4k stacks from 32bit x86 it's no longer 
     realistically maintainable for other architectures.

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Adrian Bunk wrote:
> 
> If you think we have too many stacksize problems I'd suggest to consider 
> removing the choice of 4k stacks on i386, sh and m68knommu instead of 
> using -fno-inline-functions-called-once:

Don't be silly. That makes the problem _worse_.

We're much better off with a 1% code-size reduction than forcing big 
stacks on people. The 4kB stack option is also a good way of saying "if it 
works with this, then 8kB is certainly safe".

And embedded people (the ones that might care about 1% code size) are the 
ones that would also want smaller stacks even more!

		Linus

Re: e1000 horridness (was Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected)

[Jeff Kirsher]

On Tue, Aug 26, 2008 at 1:14 PM, Kok, Auke <auke-jan.h.kok@intel.com> wrote:
> Linus Torvalds wrote:
>>
>> On Tue, 26 Aug 2008, Jeff Garzik wrote:
>>> e1000_check_options builds a struct (singular) on the stack, really... struct
>>> e1000_option is reasonably small.
>>
>> No it doesn't.
>>
>> Look a bit more closely.
>>
>> It builds a struct (singular) MANY MANY times. It also then builds up a
>> huge e1000_opt_list[] array, even though it is const and should be static
>> (and const).
>>
>> I know. I wrote a patch to FIX it.
>
> totally cool patch afaics - if I still maintained this driver I'd have this tested
> and merged right away :)
>
> I suppose Jeff Kirsher is already doing so right now

You suppose correctly.
.
>
> I suppose that he'll have to look at the other Intel ethernet drivers as well :)
>
> Jeff, please add my:
>
> Reveiewed-by: Auke Kok <auke-jan.h.kok@intel.com>
>

Will do.

-- 
Cheers,
Jeff

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Tue, Aug 26, 2008 at 5:04 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:

> And embedded people (the ones that might care about 1% code size) are the
> ones that would also want smaller stacks even more!

This is something I never understood - embedded devices are not going
to run more than a few processes and 4K*(Few Processes)
 IMHO is not worth a saving now a days even in embedded world given
falling memory prices. Or do I misunderstand?

Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[David VomLehn]

Parag Warudkar wrote:
> On Tue, Aug 26, 2008 at 5:04 PM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> 
>> And embedded people (the ones that might care about 1% code size) are the
>> ones that would also want smaller stacks even more!
> 
> This is something I never understood - embedded devices are not going
> to run more than a few processes and 4K*(Few Processes)
>  IMHO is not worth a saving now a days even in embedded world given
> falling memory prices. Or do I misunderstand?

Embedded applications span a huge range of sizes, from the very small devices to 
which you refer, to quite complex devices. The cable settop boxes we develop have 
over a hundred interrupt sources, typically run 250-300 threads, and have 192+ 
MiB of memory. For all that, we are very cost sensitive and are under constant 
pressure to come up with reliable ways to save memory.

> Parag
--
David VomLehn

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 02:04:57PM -0700, Linus Torvalds wrote:
> 
> 
> On Tue, 26 Aug 2008, Adrian Bunk wrote:
> > 
> > If you think we have too many stacksize problems I'd suggest to consider 
> > removing the choice of 4k stacks on i386, sh and m68knommu instead of 
> > using -fno-inline-functions-called-once:
> 
> Don't be silly. That makes the problem _worse_.
> 
> We're much better off with a 1% code-size reduction than forcing big 
> stacks on people. The 4kB stack option is also a good way of saying "if it 
> works with this, then 8kB is certainly safe".
>...

You implicitely assume both would solve the same problem.

While 4kB stacks are something we anyway never got 100% working, the 
cases where gcc inlining functions causes a critical increase in stack 
usage are usually not that hard to find, and once found the fix is 
trivial.

We should anyway monitor stack usages better since we have frequent 
programming errors in this area, and problems caused by gcc can this
way be detected en passant.

You have a good point that aiming at 4kB makes 8kB a very safe choice.

But I do not think the problem you'd solve with 
-fno-inline-functions-called-once is big enough to warrant the size 
increase it causes.

> 		Linus

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 04:00:33PM -0700, David VomLehn wrote:
> Parag Warudkar wrote:
>> On Tue, Aug 26, 2008 at 5:04 PM, Linus Torvalds
>> <torvalds@linux-foundation.org> wrote:
>>
>>> And embedded people (the ones that might care about 1% code size) are the
>>> ones that would also want smaller stacks even more!
>>
>> This is something I never understood - embedded devices are not going
>> to run more than a few processes and 4K*(Few Processes)
>>  IMHO is not worth a saving now a days even in embedded world given
>> falling memory prices. Or do I misunderstand?
>
> Embedded applications span a huge range of sizes, from the very small 
> devices to which you refer, to quite complex devices. The cable settop 
> boxes we develop have over a hundred interrupt sources, typically run 
> 250-300 threads, and have 192+ MiB of memory. For all that, we are very 
> cost sensitive and are under constant pressure to come up with reliable 
> ways to save memory.

As you say correctly the term "embedded" gets used for many different 
devices.

And if you have 192+ MiB of memory you have so much that all these 
kernel size discussions don't really matter.

> David VomLehn

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Parag Warudkar wrote:
> 
> This is something I never understood - embedded devices are not going
> to run more than a few processes and 4K*(Few Processes)
>  IMHO is not worth a saving now a days even in embedded world given
> falling memory prices. Or do I misunderstand?

Well, by that argument, 1% of kernel size doesn't matter either..

1% of a kernel for an embedded device is roughly 10-30kB or so depending 
on how small you make the configuration. 

If that matters, then so should the difference of 3-8 processes' kernel 
stack usage when you have a 4k/8k stack choice.

And they _all_ will have at least 3-8 processes on them. Even the simplest 
ones will tend to have many more.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Wed, 27 Aug 2008, Adrian Bunk wrote:
> > 
> > We're much better off with a 1% code-size reduction than forcing big 
> > stacks on people. The 4kB stack option is also a good way of saying "if it 
> > works with this, then 8kB is certainly safe".
> 
> You implicitely assume both would solve the same problem.

I'm just saying that your logic doesn't hold water.

If we can save kernel stack usage, then a 1% increase in kernel size is 
more than worth it.

> While 4kB stacks are something we anyway never got 100% working

What? Don't be silly. 

Linux _historically_ always used 4kB stacks.

No, they are likely not usable on x86-64, but dammit, they should be more 
than usable on x86-32 still.

> But I do not think the problem you'd solve with 
> -fno-inline-functions-called-once is big enough to warrant the size 
> increase it causes.

You continually try to see the inlining as a single solution to one 
problem (debuggability, stack, whatever).

The biggest problem with gcc inlining has always been that it has been 
_unpredictable_. It causes problems in many different ways. It has caused 
stability issues due to gcc versions doing random things. It causes the 
stack expansion. It makes stack traces harder for debugging, etc.

If it was any one thing, I wouldn't care. But it's exactly the fact that 
it causes all these problems in different areas.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 04:51:52PM -0700, Linus Torvalds wrote:
> 
> 
> On Wed, 27 Aug 2008, Adrian Bunk wrote:
> > > 
> > > We're much better off with a 1% code-size reduction than forcing big 
> > > stacks on people. The 4kB stack option is also a good way of saying "if it 
> > > works with this, then 8kB is certainly safe".
> > 
> > You implicitely assume both would solve the same problem.
> 
> I'm just saying that your logic doesn't hold water.
> 
> If we can save kernel stack usage, then a 1% increase in kernel size is 
> more than worth it.

>From some tests the size increase seems to become bigger for smaller 
kernels, but I don't have any really good data.


An interesting question is why most of our architectures for embedded 
devices only offer bigger stacks:

The only architectures offering a 4kB stacks option are:
- m68knommu
- sh
- 32bit x86

The following architectures that are used in embedded devices 
always use 8kB stacks (or bigger) in your tree:
- arm
- avr32
- blackfin
- cris
- frv
- h8300
- m32r
- m68k
- mips
- mn10300 (has an #ifdef CONFIG_4KSTACKS but no kconfig option)
- powerpc
- xtensa


> > While 4kB stacks are something we anyway never got 100% working
> 
> What? Don't be silly. 
> 
> Linux _historically_ always used 4kB stacks.
> 
> No, they are likely not usable on x86-64, but dammit, they should be more 
> than usable on x86-32 still.


When did we get callpaths like like nfs+xfs+md+scsi reliably 
working with 4kB stacks on x86-32?


>...
> 			Linus

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Wed, 27 Aug 2008, Adrian Bunk wrote:
> 
> When did we get callpaths like like nfs+xfs+md+scsi reliably 
> working with 4kB stacks on x86-32?

XFS may never have been usable, but the rest, sure.

And you seem to be making this whole argument an excuse to SUCK, adn an 
excuse to let gcc crap even more on our stack space.

Why?

Why aren't you saying that we should be able to do better? Instead, you 
seem to asking us to do even worse than we do now?

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Greg Ungerer]

Linus Torvalds wrote:
> On Tue, 26 Aug 2008, Parag Warudkar wrote:
>> This is something I never understood - embedded devices are not going
>> to run more than a few processes and 4K*(Few Processes)
>>  IMHO is not worth a saving now a days even in embedded world given
>> falling memory prices. Or do I misunderstand?
> 
> Well, by that argument, 1% of kernel size doesn't matter either..
> 
> 1% of a kernel for an embedded device is roughly 10-30kB or so depending 
> on how small you make the configuration. 
> 
> If that matters, then so should the difference of 3-8 processes' kernel 
> stack usage when you have a 4k/8k stack choice.
> 
> And they _all_ will have at least 3-8 processes on them. Even the simplest 
> ones will tend to have many more.

I have some simple devices (network access/routers) with 8MB of RAM,
at power up not really being configured to do anything running 25
processes. (Heck there is over 10 kernel processes running!). Configure
some interfaces and services and that will easily push past 40.
I'd be happy with a 160k saving :-)

The init memory being freed at the end of the kernel boot is 88k,
4k stacks could save more than that.

Regards
Greg


------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
Secure Computing Corporation                PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Tue, Aug 26, 2008 at 7:47 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:

> If that matters, then so should the difference of 3-8 processes' kernel
> stack usage when you have a 4k/8k stack choice.

The savings part -financial ones- are not always realizable with the
way memory is priced/sized/fitted.
Savings in few Mb of Kernel stack are not necessarily going to allow
getting rid of a single memory chip of 64M or so.
Either that or embedded manufacturing/configurations are different
than the desktop world.

(If my device has 2 memory slots and my user space requires 100Mb
including kernel memory - I anyways have to put in 64Mx2 there to take
advantage of mass manufactured, general purpose memory - so no big
deal if I saved 1.2Mb in Kernel stack or not. And savings of 64Mb
Kernel memory are not feasible anyways to allow user space to work
with 64Mb.)

On the other hand reducing  user space memory usage on those devices
(not counting savings from kernel stack size) is a way more attractive
option.

And although you said in your later reply that Linux x86 with 4K
stacks should be more than usable - my experiences running a untainted
desktop/file server with 4K stack have been always disastrous XFS or
not.  It _might_ work for some well defined workloads but you would
not want to risk 4K stacks otherwise.

I understand the having 4K stack option as a non-default for very
specific workloads is a good idea but apart from that I think no one
else seems to bother with reducing stack sizes (by no one I mean other
OSes.)

Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Tue, Aug 26, 2008 at 8:53 PM, Greg Ungerer <gerg@snapgear.com> wrote:

> I have some simple devices (network access/routers) with 8MB of RAM,
> at power up not really being configured to do anything running 25
> processes. (Heck there is over 10 kernel processes running!). Configure
> some interfaces and services and that will easily push past 40.
> I'd be happy with a 160k saving :-)
>

So you really need to run all 25 processes on that 8Mb box?
(For reference even the NGW100 development board comes with 16Mb RAM).

Even if you do need those all 25 processes on the 8Mb box, fixing the
memory usage of those user space hogs is lot better than trying to
save 160Kb in kernel stacks.
Last I looked, user space wasn't particularly frugal with memory usage.

Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Greg Ungerer]

Parag Warudkar wrote:
> On Tue, Aug 26, 2008 at 8:53 PM, Greg Ungerer <gerg@snapgear.com> wrote:
> 
>> I have some simple devices (network access/routers) with 8MB of RAM,
>> at power up not really being configured to do anything running 25
>> processes. (Heck there is over 10 kernel processes running!). Configure
>> some interfaces and services and that will easily push past 40.
>> I'd be happy with a 160k saving :-)
>>
> 
> So you really need to run all 25 processes on that 8Mb box?

Yes, of course. Considerable effort has been put into running
a minimal set of processes (that still for fills the required function
set of this device).


> (For reference even the NGW100 development board comes with 16Mb RAM).

Lots of development boards are fitted with lots of RAM.

And the pressure will still be on in _real_ products to reduce
the RAM footprint as much as possible. There are exceptions but
generally less is cheaper. Simple economics really.


> Even if you do need those all 25 processes on the 8Mb box, fixing the
> memory usage of those user space hogs is lot better than trying to
> save 160Kb in kernel stacks.

Yep, been done too. You don't squeeze a lot into these smaller
devices without looking at everything in it.


> Last I looked, user space wasn't particularly frugal with memory usage.

Then you haven't looked in the right places :-)

There are plenty of choices for making things small in user space.
Simple stuff like using uClibc, busybox, etc.

In this specific example things like /bin/init is 10k, /bin/inetd
is 10k, /bin/crond is 11k, etc. (Ofcourse it is a shared uClibc setup,
uClibc is ~300k). And XIP can help out here too.

Regards
Greg



------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
Secure Computing Corporation                PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Parag Warudkar wrote:
>
> And although you said in your later reply that Linux x86 with 4K
> stacks should be more than usable - my experiences running a untainted
> desktop/file server with 4K stack have been always disastrous XFS or
> not.  It _might_ work for some well defined workloads but you would
> not want to risk 4K stacks otherwise.

Umm. How long?

4kB used to be the _only_ choice. And no, there weren't even irq stacks. 
So that 4kB was not just the whole kernel call-chain, it was also all the 
irq nesting above it.

And yes, we've gotten much worse over time, and no, I can't really suggest 
going back to that in general. The code bloat has certainly been 
accompanied by a stack bloat too.

But part of it is definitely gcc. Some versions of gcc used to be 
absolutely _horrid_ when it came to stack usage, especially with some 
flags, and especially with the crazy inlining that module-at-a-time 
caused.

But I'd be really happy if some embedded people tried to take some of that 
bloat back, and aim for 4kB stacks. Because it's definitely not 
unrealistic. At least it _shouldn't_ be. And a lot of the cases of us 
having structures on the stack is actually not worth it, and tends to be 
about being lazy rather than anything else.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Tue, Aug 26, 2008 at 9:31 PM, Greg Ungerer <gerg@snapgear.com> wrote:

>
> And the pressure will still be on in _real_ products to reduce
> the RAM footprint as much as possible. There are exceptions but
> generally less is cheaper. Simple economics really.

Well, sure  - but the industry as a whole seems to have gone the other
way - do more with more at the similar or lower price points!
By that definition of less is better we should try and make the kernel
memory pageable (or has someone already done that?) - Windows does it,
by default ;)

Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Tue, Aug 26, 2008 at 9:49 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
>
> On Tue, 26 Aug 2008, Parag Warudkar wrote:
>>
>> And although you said in your later reply that Linux x86 with 4K
>> stacks should be more than usable - my experiences running a untainted
>> desktop/file server with 4K stack have been always disastrous XFS or
>> not.  It _might_ work for some well defined workloads but you would
>> not want to risk 4K stacks otherwise.
>
> Umm. How long?
>

IIRC the last I tried 4K stacks with x86 was on 2.6.21 - Fedora 7
kernel, around June 07 time frame.
The oops included a ugly and long call trace that I still remember.

> And a lot of the cases of us
> having structures on the stack is actually not worth it, and tends to be
> about being lazy rather than anything else.

What about deep call chains? The problem with the uptake of 4K stacks
seems to be that is not reliably provable that it will work under all
circumstances.

Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 26 Aug 2008, Parag Warudkar wrote:
> 
> What about deep call chains? The problem with the uptake of 4K stacks
> seems to be that is not reliably provable that it will work under all
> circumstances.

Umm. Neither is 8k stacks. Nobody "proved" anything.

But yes, some subsystems have insanely deep call chains. And yes, things 
like the VFS recursion (for symlinks) makes that deeper yet for 
filesystems, although only on the lookup path. And that is exactly the 
kind of thing that can exacerbate the problem of the compiler artificially 
making for a bigger stack footprint of a function (*).

For things like the VFS layer, right now we allow a nesting level of 8, I 
think. If I remember correctly, it was 5 historically. Part of raising 
that depth, though, was that we actually moved the recursive part into 
fs/namei.c, and the nesting stack-depth was something pretty damn small 
when the filesystem used "follow_link" properly and let the VFS do it for 
it (ie the callchain to actually look up the link could be deep, but it 
would not recurse back, and instead just return a pointer, so that the 
actual _recursive_ part was just __do_follow_link() and is just a few 
words on the stack).

So yes, we do have some deep callchains, but they tend to be pretty well 
managed for _good_ code. The problems tend to be the areas with lots of 
indirection layers, and yeah, XFS, MD and ACPI all have those kinds of 
things.

In an embdedded world, many of those should be a non-issue, though. 

			Linus

(*) ie the function that _is_ on the deep chain doesn't actually need much 
of a stack footprint at all itself, but it may call a helper function that 
is _not_ in the deep chain, and if it gets inlined it may give its 
excessive stack footprint to the deep chain - and this is _exactly_ the 
problem that happened with inlining "load_module()".

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Paul Mackerras]

Linus Torvalds writes:

> 4kB used to be the _only_ choice. And no, there weren't even irq stacks. 
> So that 4kB was not just the whole kernel call-chain, it was also all the 
> irq nesting above it.

I think your memory is failing you.  In 2.4 and earlier, the kernel
stack was 8kB minus the size of the task_struct, which sat at the
start of the 8kB.  For instance, from include/asm-i386/processor.h for
2.4.29:

#define THREAD_SIZE (2*PAGE_SIZE)
#define alloc_task_struct() ((struct task_struct *) __get_free_pages(GFP_KERNEL,1))
#define free_task_struct(p) free_pages((unsigned long) (p), 1)

Paul.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Nick Piggin]

On Wednesday 27 August 2008 06:01, Mike Travis wrote:
> Dave Jones wrote:
> ...
>
> > But yes, for this to be even remotely feasible, there has to be a
> > negligable performance cost associated with it, which right now, we
> > clearly don't have. Given that the number of people running 4096 CPU
> > boxes even in a few years time will still be tiny, punishing the common
> > case is obviously absurd.
> >
> > 	Dave
>
> I did do some fairly extensive benchmarking between configs of NR_CPUS =
> 128 and 4096 and most performance hits were in the neighborhood of < 5% on
> systems with 8 cpus and 4GB of memory (our most common test system).

5% is a pretty nasty performance hit... what sort of benchmarks are we
talking about here?

I just made some pretty crazy changes to the VM to get "only" around 5
or so % performance improvement in some workloads.

What places are making heavy use of cpumasks that causes such a slowdown?
Hopefully callers can mostly be improved so they don't need to use cpumasks
for common cases.

Until then, it would be kind of sad for a distro to ship a generic x86
kernel and lose 5% performance because it is set to 4096 CPUs...

But if I misunderstand and you're talking about specific microbenchmarks to
find the worst case for huge cpumasks, then I take that back.


> [But 
> changing cpumask_t's to be pointers instead of values will likely increase
> this.]  I've tried to be very sensitive to this issue with all my previous
> changes, so convincing the distros to set NR_CPUS=4096 would be as painless
> for them as possible. ;-)
>
> Btw, huge count cpu systems I don't think are that far away.  I believe the
> nextgen Larabbee chips will be geared towards HPC applications [instead of
> just GFX apps], and putting 4 of these chips on a motherboard would add up
> to 512 cpu threads (1024 if they support hyperthreading.)

It would be quite interesting if they make them cache coherent / MP capable.
Will they be?

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[David Miller]

From: Nick Piggin <nickpiggin@yahoo.com.au>
Date: Wed, 27 Aug 2008 16:54:32 +1000

> 5% is a pretty nasty performance hit... what sort of benchmarks are we
> talking about here?
> 
> I just made some pretty crazy changes to the VM to get "only" around 5
> or so % performance improvement in some workloads.
> 
> What places are making heavy use of cpumasks that causes such a slowdown?
> Hopefully callers can mostly be improved so they don't need to use cpumasks
> for common cases.

It's almost certainly from the cross-call dispatch call chain.

As just one example, just to do a TLB flush mm->cpu_vm_mask probably
gets passed around as an aggregate two or three times on the way down
to the APIC programming code on x86.  That's two or three 512 byte
copies on the stack :)

Look at the sparc64 SMP code for how I solved the problem there.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Nick Piggin]

On Wednesday 27 August 2008 17:05, David Miller wrote:
> From: Nick Piggin <nickpiggin@yahoo.com.au>
> Date: Wed, 27 Aug 2008 16:54:32 +1000
>
> > 5% is a pretty nasty performance hit... what sort of benchmarks are we
> > talking about here?
> >
> > I just made some pretty crazy changes to the VM to get "only" around 5
> > or so % performance improvement in some workloads.
> >
> > What places are making heavy use of cpumasks that causes such a slowdown?
> > Hopefully callers can mostly be improved so they don't need to use
> > cpumasks for common cases.
>
> It's almost certainly from the cross-call dispatch call chain.
>
> As just one example, just to do a TLB flush mm->cpu_vm_mask probably
> gets passed around as an aggregate two or three times on the way down
> to the APIC programming code on x86.  That's two or three 512 byte
> copies on the stack :)

Yeah, I see. That's stupid isn't it? (Well, I guess it was completely
sane when cpumasks were word sized ;))

Hopefully that accounts for a significant chunk...

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan Cox]

> You have a good point that aiming at 4kB makes 8kB a very safe choice.

Not really no - we use separate IRQ stacks in 4K but not 8K mode on
x86-32. That means you've actually got no more space if you are unlucky
with the timing of events. The 8K mode is merely harder to debug.

If 4K stacks really are not safe then x86-32 really really needs to
switch to using IRQ stacks in 8K stack mode as well.

Alan

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan Cox]

> What about deep call chains? The problem with the uptake of 4K stacks
> seems to be that is not reliably provable that it will work under all
> circumstances.

On x86-32 with 8K stacks your IRQ paths share them so that is even harder
to prove (not that you can prove any of them) and the bugs are more
obscure and random.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Bernd Petrovitsch]

On Tue, 2008-08-26 at 18:54 -0400, Parag Warudkar wrote:
> On Tue, Aug 26, 2008 at 5:04 PM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> 
> > And embedded people (the ones that might care about 1% code size) are the
> > ones that would also want smaller stacks even more!
> 
> This is something I never understood - embedded devices are not going
> to run more than a few processes and 4K*(Few Processes)
>  IMHO is not worth a saving now a days even in embedded world given
> falling memory prices. Or do I misunderstand?

Falling prices are no reason to increase the amount of available RAM (or
other hardware).
Especially if you (intend to) build >1E5 devices - where every Euro
counts.

	Bernd
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Bernd Petrovitsch]

On Tue, 2008-08-26 at 22:16 -0400, Parag Warudkar wrote:
[...]
> Well, sure  - but the industry as a whole seems to have gone the other

"The industry as a whole" doesn't exist on that low level. You can't
compare the laptop and/or desktop computer market (where one may buy
today hardware that runs in 3 years with the next generation/release of
the OS and applications) with the e.g. "WLAN router" market where - from
the commercial point of view - every Euro counts (and where the
requirements for the lifetime of the device are long frozen before the
thing gets in a shop).

> way - do more with more at the similar or lower price points!
> By that definition of less is better we should try and make the kernel
> memory pageable (or has someone already done that?) - Windows does it,

That doesn't help as in really small devices (like WLAN routers, cable
modems, etc.) you run without any means of paging/swapping. And even
binaries/read-only files are not necessarily executable in place (but
must be loaded into RAM). So you can't flush these pages.

And pageable kernel memory doesn't come for free - even if one only
counts the increased code and it's complexity.

> by default ;)

Which is more a sign that it is probably a very bad idea.

	Bernd
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[David Miller]

From: Nick Piggin <nickpiggin@yahoo.com.au>
Date: Wed, 27 Aug 2008 17:47:14 +1000

> Yeah, I see. That's stupid isn't it? (Well, I guess it was completely
> sane when cpumasks were word sized ;))
> 
> Hopefully that accounts for a significant chunk...

There is a lot of indirect costs that are hard to see as well.

Two things a lot of these cross-call dispatch paths do is:

1) Clear self-cpu

2) AND with cpus_online

#1 can normally be a simple bit clear, but some places can also
implement this with something like "cpus_andn(X, cpumask_of_cpu(cpu))"

It's simply easier to move those two things down to the bottom of
the APIC programming code, they just loop over the cpumask doing
an expensive APIC I/O operation anyways, might as well overlap it
with these "skip self-cpu" and "skip not-online cpus" checks.

And oh yeah we get the stack wastage fixed too, isn't what what we
were talking about? :-)

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Bernd Petrovitsch]

On Tue, 2008-08-26 at 20:58 -0400, Parag Warudkar wrote:
[...]
> The savings part -financial ones- are not always realizable with the
> way memory is priced/sized/fitted.
> Savings in few Mb of Kernel stack are not necessarily going to allow
> getting rid of a single memory chip of 64M or so.

No, but you can put an additional service(s) on it and sales people have
one (or two or ....) line more for their sales brochures.

> Either that or embedded manufacturing/configurations are different
> than the desktop world.

They are different. Think of running the complete system acting as a
bridge, router and/or firewall (Kernel early 2.4 though) from 4MB flash
in 32MB RAM and - listing the outside visible services - having a
command-line interface, web-GUI (implying a http server) and and a
(net-)SNMP agent on it.
Running a glibc without thread support is win there (implying that there
is no thread support available on that device).

> (If my device has 2 memory slots and my user space requires 100Mb
> including kernel memory - I anyways have to put in 64Mx2 there to take
> advantage of mass manufactured, general purpose memory - so no big
> deal if I saved 1.2Mb in Kernel stack or not. And savings of 64Mb
> Kernel memory are not feasible anyways to allow user space to work
> with 64Mb.)

As soon as product management realizes that there is space left on the
device, they get new ideas and/or customer requirements to run more
services on that device.

> On the other hand reducing  user space memory usage on those devices
> (not counting savings from kernel stack size) is a way more attractive
> option.

There is no question if save space here or there. You save it - sooner
or later - on all fronts. Period.

> And although you said in your later reply that Linux x86 with 4K
> stacks should be more than usable - my experiences running a untainted
> desktop/file server with 4K stack have been always disastrous XFS or
> not.  It _might_ work for some well defined workloads but you would
> not want to risk 4K stacks otherwise.

The embedded world of really small devices usually doesn't run XFS (or
ext? or reiser* of jfs or NFS or ...) or stacks block devices on files
or .....

> I understand the having 4K stack option as a non-default for very
> specific workloads is a good idea but apart from that I think no one
> else seems to bother with reducing stack sizes (by no one I mean other
> OSes.)

They probably gave the idea pretty soon because you need to
rework/improve large parts of the kernel + drivers (and that has two
major problems - it consumes a lot of man power for "no new features and
everything must be completely tested again"[0] and it adds new risks).
And that is practically impossible if one sells "stable driver APIs" for
3rd party (commercial) drivers because these must be changed too.

	Bernd

[0]: Let alone if you (or your customers) need certificates from some
     governmental agencys.
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Arjan van de Ven]

Paul Mackerras wrote:
> Linus Torvalds writes:
> 
>> 4kB used to be the _only_ choice. And no, there weren't even irq stacks. 
>> So that 4kB was not just the whole kernel call-chain, it was also all the 
>> irq nesting above it.
> 
> I think your memory is failing you.  In 2.4 and earlier, the kernel
> stack was 8kB minus the size of the task_struct, which sat at the
> start of the 8kB.  For instance, from include/asm-i386/processor.h for
> 2.4.29:

but was shared with interrupts; so out of the 6Kb left, you had still really only 4Kb for user context stack

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 05:28:37PM -0700, Linus Torvalds wrote:
> 
> 
> On Wed, 27 Aug 2008, Adrian Bunk wrote:
> > 
> > When did we get callpaths like like nfs+xfs+md+scsi reliably 
> > working with 4kB stacks on x86-32?
> 
> XFS may never have been usable, but the rest, sure.
> 
> And you seem to be making this whole argument an excuse to SUCK, adn an 
> excuse to let gcc crap even more on our stack space.
> 
> Why?
> 
> Why aren't you saying that we should be able to do better? Instead, you 
> seem to asking us to do even worse than we do now?

My main point is:
- getting 4kB stacks working reliably is a hard task
- having an eye on gcc increasing the stack usage, and fixing it if
  required, is relatively easy

If we should be able to do better at getting (and keeping) 4kB stacks 
working, then coping with possible inlining problems caused by gcc
should not be a big problem for us.

> 			Linus

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Tue, Aug 26, 2008 at 06:49:19PM -0700, Linus Torvalds wrote:
>...
> But part of it is definitely gcc. Some versions of gcc used to be 
> absolutely _horrid_ when it came to stack usage, especially with some 
> flags, and especially with the crazy inlining that module-at-a-time 
> caused.
>...

That was gcc 3.4.

And due to that we disable unit-at-a-time for gcc 3.4 on 32bit x86.

> 			Linus

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Wed, Aug 27, 2008 at 4:25 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>> You have a good point that aiming at 4kB makes 8kB a very safe choice.
>
> Not really no - we use separate IRQ stacks in 4K but not 8K mode on
> x86-32. That means you've actually got no more space if you are unlucky
> with the timing of events. The 8K mode is merely harder to debug.
>

By your logic though, XFS on x86 should work fine with 4K stacks -
many will attest that it does not and blows up due to stack issues.

I have first hand experiences of things blowing up with deep call
chains when using 4K stacks where 8K worked just fine on same
workload.

So there is definitely some other problem with 4K stacks.

Thanks
Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Wed, Aug 27, 2008 at 5:00 AM, Bernd Petrovitsch <bernd@firmix.at> wrote:

>
> They probably gave the idea pretty soon because you need to
> rework/improve large parts of the kernel + drivers (and that has two
> major problems - it consumes a lot of man power for "no new features and
> everything must be completely tested again"[0] and it adds new risks).
> And that is practically impossible if one sells "stable driver APIs" for
> 3rd party (commercial) drivers because these must be changed too.
>

But not many embedded Linux arches support 4K stacks like Adrian
pointed out earlier.
So the same (lot of man power requirement) would apply to Linux.

Sure it will be good - but how reasonable it is to attempt it and how
reliably it will work under all conceived loads - those are the
questions.

Thanks

Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Bernd Petrovitsch]

On Wed, 2008-08-27 at 08:56 -0400, Parag Warudkar wrote:
> On Wed, Aug 27, 2008 at 5:00 AM, Bernd Petrovitsch <bernd@firmix.at> wrote:
> > They probably gave the idea pretty soon because you need to
> > rework/improve large parts of the kernel + drivers (and that has two
> > major problems - it consumes a lot of man power for "no new features and
> > everything must be completely tested again"[0] and it adds new risks).
> > And that is practically impossible if one sells "stable driver APIs" for
> > 3rd party (commercial) drivers because these must be changed too.
> 
> But not many embedded Linux arches support 4K stacks like Adrian

What is an "embedded Linux arch"?
Personally I encountered i386, ARM, MIPS and PPC in the embedded world.

> pointed out earlier.
> So the same (lot of man power requirement) would apply to Linux.

Of course. Look at the amount of work done by lots of people in that
area (including stack frame size reductions) and on-going discussions.

> Sure it will be good - but how reasonable it is to attempt it and how
> reliably it will work under all conceived loads - those are the
> questions.

If you "develop" an embedded system (which is partly system integration
of existing apps) to be installed in the field, you don't have that many
conceivable work loads compared to a desktop/server system. And you have
a fixed list of drivers and applications.
A usual approach is to run stress tests on several (or all)
subsystems/services/... in parallel and if the device survives it
functioning correctly, it is at least good enough.

	Bernd
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Alan Cox]

> By your logic though, XFS on x86 should work fine with 4K stacks -
> many will attest that it does not and blows up due to stack issues.
> 
> I have first hand experiences of things blowing up with deep call
> chains when using 4K stacks where 8K worked just fine on same
> workload.
> 
> So there is definitely some other problem with 4K stacks.

Nothing of the sort. If it blows up with a 4K stack it will almost
certainly blow up with an 8K stack *eventually* - when a heavy stack usage
coincides with a heavy stack using IRQ handler.

You won't catch it in simple testing, you won't catch it in trivial
simulation and it'll be incredibly hard to reproduce. Not the kind of bug
you want in a production system really. IRQ stacks make things much more
predictable.

Alan

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Nick Piggin wrote:
> On Wednesday 27 August 2008 06:01, Mike Travis wrote:
>> Dave Jones wrote:
>> ...
>>
>>> But yes, for this to be even remotely feasible, there has to be a
>>> negligable performance cost associated with it, which right now, we
>>> clearly don't have. Given that the number of people running 4096 CPU
>>> boxes even in a few years time will still be tiny, punishing the common
>>> case is obviously absurd.
>>>
>>> 	Dave
>> I did do some fairly extensive benchmarking between configs of NR_CPUS =
>> 128 and 4096 and most performance hits were in the neighborhood of < 5% on
>> systems with 8 cpus and 4GB of memory (our most common test system).
> 
> 5% is a pretty nasty performance hit... what sort of benchmarks are we
> talking about here?

It's been a while now, I should go back and check my notes.  Many of the
BM's did not have any changes.  I believe the ones that were right on the
edge of paging were affected by the fact that less memory was available.
> 
> I just made some pretty crazy changes to the VM to get "only" around 5
> or so % performance improvement in some workloads.
> 
> What places are making heavy use of cpumasks that causes such a slowdown?
> Hopefully callers can mostly be improved so they don't need to use cpumasks
> for common cases.

That's another study I did, and it seemed that maybe 95% of the functions
would not be affected by passing pointers to cpumasks instead of the cpumasks
themselves, because the data was processed by a cpu_xxx function that
uses a pointer.  Most commonly was to create a temp cpumask, using
cpus_and(temp_mask, callers_mask, cpu_online_map);  The speedup to use nr_cpu_ids
instead of NR_CPUS in the traversal functions helped quite a bit.  Using this
same method in the cpus_xxx functions would further speed up things.  (As
well as only allocating the cpumask sized by nr_cpu_ids instead of NR_CPUS
as the current cpumask_t definition specifies.)

> 
> Until then, it would be kind of sad for a distro to ship a generic x86
> kernel and lose 5% performance because it is set to 4096 CPUs...
> 
> But if I misunderstand and you're talking about specific microbenchmarks to
> find the worst case for huge cpumasks, then I take that back.

Yes, I was (at the time) trying to determine how many of the cpumask functions
were actually in play by user tasks, so I was zeroing in on those (cpusets,
rescheds, etc.)

> 
> 
>> [But 
>> changing cpumask_t's to be pointers instead of values will likely increase
>> this.]  I've tried to be very sensitive to this issue with all my previous
>> changes, so convincing the distros to set NR_CPUS=4096 would be as painless
>> for them as possible. ;-)
>>
>> Btw, huge count cpu systems I don't think are that far away.  I believe the
>> nextgen Larabbee chips will be geared towards HPC applications [instead of
>> just GFX apps], and putting 4 of these chips on a motherboard would add up
>> to 512 cpu threads (1024 if they support hyperthreading.)
> 
> It would be quite interesting if they make them cache coherent / MP capable.
> Will they be?

There's not been a lot of info available yet, but I think the 128 cores will
share at least an L2 cache + memory controller.  How the APIC's interact is
also another big question.  And most likely some standard system controller
CPU will be needed, but that could be a tiny VIA processor... ;-)

Thanks,
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

David Miller wrote:
> From: Nick Piggin <nickpiggin@yahoo.com.au>
> Date: Wed, 27 Aug 2008 16:54:32 +1000
> 
>> 5% is a pretty nasty performance hit... what sort of benchmarks are we
>> talking about here?
>>
>> I just made some pretty crazy changes to the VM to get "only" around 5
>> or so % performance improvement in some workloads.
>>
>> What places are making heavy use of cpumasks that causes such a slowdown?
>> Hopefully callers can mostly be improved so they don't need to use cpumasks
>> for common cases.
> 
> It's almost certainly from the cross-call dispatch call chain.
> 
> As just one example, just to do a TLB flush mm->cpu_vm_mask probably
> gets passed around as an aggregate two or three times on the way down
> to the APIC programming code on x86.  That's two or three 512 byte
> copies on the stack :)
> 
> Look at the sparc64 SMP code for how I solved the problem there.

I will, thanks!

Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

David Miller wrote:
> From: Nick Piggin <nickpiggin@yahoo.com.au>
> Date: Wed, 27 Aug 2008 17:47:14 +1000
> 
>> Yeah, I see. That's stupid isn't it? (Well, I guess it was completely
>> sane when cpumasks were word sized ;))
>>
>> Hopefully that accounts for a significant chunk...
> 
> There is a lot of indirect costs that are hard to see as well.
> 
> Two things a lot of these cross-call dispatch paths do is:
> 
> 1) Clear self-cpu
> 
> 2) AND with cpus_online
> 
> #1 can normally be a simple bit clear, but some places can also
> implement this with something like "cpus_andn(X, cpumask_of_cpu(cpu))"
> 
> It's simply easier to move those two things down to the bottom of
> the APIC programming code, they just loop over the cpumask doing
> an expensive APIC I/O operation anyways, might as well overlap it
> with these "skip self-cpu" and "skip not-online cpus" checks.
> 
> And oh yeah we get the stack wastage fixed too, isn't what what we
> were talking about? :-)

Yes, the most time consuming part was determining whether a kmalloc
could safely be used in the context of the function, and what to
do about the out-of-memory problem.  Pushing that down to something
like:  for_each_cpu_thats_online(cpu, *maskptr) would remove the need for
many of the temp masks.  A simple if (cpu != me) would take care of
excluding self.  It might have better interaction with cpu hotplug
as well, since the online map would be checked just before the call
to that cpu is made.

Thanks,
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Wed, 27 Aug 2008, Paul Mackerras wrote:
> 
> I think your memory is failing you.  In 2.4 and earlier, the kernel
> stack was 8kB minus the size of the task_struct, which sat at the
> start of the 8kB.

Yup, you're right.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jamie Lokier]

Bernd Petrovitsch wrote:
> If you "develop" an embedded system (which is partly system integration
> of existing apps) to be installed in the field, you don't have that many
> conceivable work loads compared to a desktop/server system. And you have
> a fixed list of drivers and applications.

Hah!  Not in my line of embedded device.

32MB no-MMU ARM boards which people run new things and attach new
devices to rather often - without making new hardware.  Volume's too
low per individual application to get new hardware designed and made.

I'm seriously thinking of forwarding porting the 4 year old firmware
from 2.4.26 to 2.6.current, just to get new drivers and capabilities.
Backporting is tedious, so's feeling wretchedly far from the mainline
world.

> A usual approach is to run stress tests on several (or all)
> subsystems/services/... in parallel and if the device survives it
> functioning correctly, it is at least good enough.

Per application.

Some little devices run hundreds of different applications and
customers expect to customise, script themselves, and attach different
devices (over USB).  The next customer in the chain expects the bits
you supplied to work in a variety of unexpected situations, even when
you advise that it probably won't do that.

Much like desktop/server Linux, but on a small device where silly
little things like 'create a process' are a stress for the dear little
thing.

(My biggest lesson: insist on an MMU next time!)

-- Jamie

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Paul Mundt]

On Wed, Aug 27, 2008 at 02:58:30PM +0300, Adrian Bunk wrote:
> On Tue, Aug 26, 2008 at 05:28:37PM -0700, Linus Torvalds wrote:
> > On Wed, 27 Aug 2008, Adrian Bunk wrote:
> > > 
> > > When did we get callpaths like like nfs+xfs+md+scsi reliably 
> > > working with 4kB stacks on x86-32?
> > 
> > XFS may never have been usable, but the rest, sure.
> > 
> > And you seem to be making this whole argument an excuse to SUCK, adn an 
> > excuse to let gcc crap even more on our stack space.
> > 
> > Why?
> > 
> > Why aren't you saying that we should be able to do better? Instead, you 
> > seem to asking us to do even worse than we do now?
> 
> My main point is:
> - getting 4kB stacks working reliably is a hard task
> - having an eye on gcc increasing the stack usage, and fixing it if
>   required, is relatively easy
> 
> If we should be able to do better at getting (and keeping) 4kB stacks 
> working, then coping with possible inlining problems caused by gcc
> should not be a big problem for us.
> 
Out of the architectures you've mentioned for 4k stacks, they also tend
to do IRQ stacks, which is something you seem to have overlooked.

In addition to that, debugging the runaway stack users on 4k tends to be
easier anyways since you end up blowing the stack a lot sooner. On sh
we've had pretty good luck with it, though most of our users are using
fairly deterministic workloads and continually profiling the footprint.
Anything that runs away or uses an insane amount of stack space needs to
be fixed well before that anyways, so catching it sooner is always
preferable. I imagine the same case is true for m68knommu (even sans IRQ
stacks).

Things might be more sensitive on x86, but it's certainly not something
that's a huge problem for the various embedded platforms to wire up,
whether they want to go the IRQ stack route or not.

In any event, lack of support for something on embedded architectures in
the kernel is more often due to apathy/utter indifference on the part of
the architecture maintainer rather than being indicative of any intrinsic
difficulty in supporting the thing in question. Most new "features" on the
lesser maintained architectures tend to end up there either out of peer
pressure or copying-and-pasting accidents rather than any sort of design.
;-)

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jamie Lokier]

Linus Torvalds wrote:
> > Most LOCs of the kernel are not written by people like you or Al Viro or 
> > David Miller, and the average kernel developer is unlikely to do it as 
> > good as gcc.
> 
> Sure. But we do have tools. We do have checkstack.pl, it's just that it 
> hasn't been an issue in a long time, so I suspect many people didn't even 
> _realize_ we have it, and I certainly can attest to the fact that even 
> people who remember it - like me - don't actually tend to run it all that 
> often.

Sounds like what's really desired here isn't more worry and
unpredictability, but for GCC+Binutils to gain the ability to
calculate the stack depth over all callchains (doesn't have to be
exact, just an upper bound; annotate recursions) in a way that's good
enough to do on every compile, complain if a depth is exceeded
statically (or it can't be proven), and to gain the
architecture-independent option "optimise to reduce stack usage".

> > BTW:
> > I just ran checkstack on a (roughly) allyesconfig kernel, and we have a 
> > new driver that allocates "unsigned char recvbuf[1500];" on the stack...
> 
> Yeah, it's _way_ too easy to do bad things.

In my userspace code, I have macros tmp_alloc and tmp_free.  They must
be matched in the same function:

     unsigned char * recvbuf = tmp_alloc(1500);
     ....
     tmp_free(recvbuf);

When stack is plentiful, it maps to alloca() which is roughly
equivalent to using a stack variable.

When stack is constrained (as it is on my little devices), that maps
to xmalloc/free.  The kernel equivalent would be kmalloc GFP_ATOMIC
(perhaps).

With different macros to mine, it may be possible to map small
fixed-size requests exactly onto local variables, and large ones to
kmalloc().  A stab at it (not tested):

    #define LOCAL_ALLOC_THRESHOLD     128

    #define LOCAL_ALLOC(type, ptr)                                        \
        __typeof__(type) __attribute__((__unused__)) ptr##_local_struct;  \
        __typeof__(type) * ptr =                                          \
              ((__builtin_constant_p(sizeof(type))                        \
                && sizeof(type) <= LOCAL_ALLOC_THRESHOLD)                 \
               ? &ptr##_local_struct : kmalloc(sizeof(type), GFP_ATOMIC))

    #define LOCAL_FREE(ptr)                           \
        ((__builtin_constant_p(sizeof (*(ptr)))       \
          && sizeof(*(ptr)) <= LOCAL_ALLOC_THRESHOLD) \
         ? (void) 0 : kfree(ptr))

Would that be useful in the kernel?

I'm thinking if it were a commonly used pattern for temporary buffers,
unknown structures and arrays of macro-determined size, the "new
driver" author would be less likely to accidentally drop a big object
on the stack.

Obviously it would be nicer for GCC to code such a thing
automatically, but that really is wishful thinking.

-- Jamie

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Parag Warudkar]

On Wed, Aug 27, 2008 at 9:21 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>> By your logic though, XFS on x86 should work fine with 4K stacks -
>> many will attest that it does not and blows up due to stack issues.
>>
>> I have first hand experiences of things blowing up with deep call
>> chains when using 4K stacks where 8K worked just fine on same
>> workload.
>>
>> So there is definitely some other problem with 4K stacks.
>
> Nothing of the sort. If it blows up with a 4K stack it will almost
> certainly blow up with an 8K stack *eventually* - when a heavy stack usage
> coincides with a heavy stack using IRQ handler.
>
> You won't catch it in simple testing, you won't catch it in trivial
> simulation and it'll be incredibly hard to reproduce. Not the kind of bug
> you want in a production system really. IRQ stacks make things much more
> predictable.


I see - so if I end up having a workload on 8k where heavy stack using
IRQs and deep kernel call chains come at the same time - even 8K will
blow up.
So 4K will blow too except that it doesn't require IRQs also to use
heavy stack, just XFS is good enough :)

It then seems like the IRQs using lot of stack is not so much of a
problem in the current kernel as much as deeper call chains and stack
usage of normal non-irq path code is.
So 8k makes it possible for the deeper call chains of non-irq path to
survive since they get better part of the 8K to themselves and IRQs
can do with less almost always.

At least that's what I can derive from the fact that we do not have
lots of reports of 8K stack blowing up.

Thanks

Parag

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Bernd Petrovitsch]

On Wed, 2008-08-27 at 16:48 +0100, Jamie Lokier wrote:
> Bernd Petrovitsch wrote:
> > If you "develop" an embedded system (which is partly system integration
> > of existing apps) to be installed in the field, you don't have that many
> > conceivable work loads compared to a desktop/server system. And you have
> > a fixed list of drivers and applications.
> 
> Hah!  Not in my line of embedded device.
> 
> 32MB no-MMU ARM boards which people run new things and attach new
> devices to rather often - without making new hardware.  Volume's too
> low per individual application to get new hardware designed and made.

Yes, you may have several products on the same hardware with somewhat
differing requirements (or not). But that is much less than a general
purpose system IMHO.

> I'm seriously thinking of forwarding porting the 4 year old firmware
> from 2.4.26 to 2.6.current, just to get new drivers and capabilities.

That sounds reasonable (and I never meant maintaining the old system
infinitely. Actually once the thing is shipped it usually enters deep
maintenance mode and the next is more a fork from the old).

> Backporting is tedious, so's feeling wretchedly far from the mainline
> world.

ACK. But that also depends on amount local changes (and sorry, but not
all locally necessary patches would be accepted in mainline in any way).

> > A usual approach is to run stress tests on several (or all)
> > subsystems/services/... in parallel and if the device survives it
> > functioning correctly, it is at least good enough.
> 
> Per application.
> 
> Some little devices run hundreds of different applications and
> customers expect to customise, script themselves, and attach different
> devices (over USB).  The next customer in the chain expects the bits
> you supplied to work in a variety of unexpected situations, even when
> you advise that it probably won't do that.

Basically their problem. Yes, "they" actually think they get a Linux
system where they can do everything and it simply works.

Oh, that's obviously not a usual "WLAN-router style" of product (where
you are not expected to actually login on a console or per ssh).

> Much like desktop/server Linux, but on a small device where silly
> little things like 'create a process' are a stress for the dear little
> thing.
> 
> (My biggest lesson: insist on an MMU next time!)

ACK. We avoid MMU-less hardware too - especially since there is enough
hardware with a MMU around.

	Bernd
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Thu, Aug 28, 2008 at 01:00:52AM +0900, Paul Mundt wrote:
> On Wed, Aug 27, 2008 at 02:58:30PM +0300, Adrian Bunk wrote:
> > On Tue, Aug 26, 2008 at 05:28:37PM -0700, Linus Torvalds wrote:
> > > On Wed, 27 Aug 2008, Adrian Bunk wrote:
> > > > 
> > > > When did we get callpaths like like nfs+xfs+md+scsi reliably 
> > > > working with 4kB stacks on x86-32?
> > > 
> > > XFS may never have been usable, but the rest, sure.
> > > 
> > > And you seem to be making this whole argument an excuse to SUCK, adn an 
> > > excuse to let gcc crap even more on our stack space.
> > > 
> > > Why?
> > > 
> > > Why aren't you saying that we should be able to do better? Instead, you 
> > > seem to asking us to do even worse than we do now?
> > 
> > My main point is:
> > - getting 4kB stacks working reliably is a hard task
> > - having an eye on gcc increasing the stack usage, and fixing it if
> >   required, is relatively easy
> > 
> > If we should be able to do better at getting (and keeping) 4kB stacks 
> > working, then coping with possible inlining problems caused by gcc
> > should not be a big problem for us.
> > 
> Out of the architectures you've mentioned for 4k stacks, they also tend
> to do IRQ stacks, which is something you seem to have overlooked.

No, I am aware of that, and on i386 IRQ stacks are only used with
4kB stacks.

On i386 it is effectively a step from 6kB to 4kB.

> In addition to that, debugging the runaway stack users on 4k tends to be
> easier anyways since you end up blowing the stack a lot sooner. On sh
> we've had pretty good luck with it, though most of our users are using
> fairly deterministic workloads and continually profiling the footprint.
> Anything that runs away or uses an insane amount of stack space needs to
> be fixed well before that anyways, so catching it sooner is always
> preferable. I imagine the same case is true for m68knommu (even sans IRQ
> stacks).

CONFIG_DEBUG_STACKOVERFLOW should give you the same information, and if
wanted with an arbitrary limit.

> Things might be more sensitive on x86, but it's certainly not something
> that's a huge problem for the various embedded platforms to wire up,
> whether they want to go the IRQ stack route or not.

How many platforms use 4kB stacks on sh?

Only 1 out of 34 defconfigs uses it.

Are there any numbers for real life usage.

> In any event, lack of support for something on embedded architectures in
> the kernel is more often due to apathy/utter indifference on the part of
> the architecture maintainer rather than being indicative of any intrinsic
> difficulty in supporting the thing in question. Most new "features" on the
> lesser maintained architectures tend to end up there either out of peer
> pressure or copying-and-pasting accidents rather than any sort of design.
> ;-)

arm or powerpc aren't exactly lesser maintained architectures.

4kB has shown to be a hard to achieve limit. After more than 4 years in 
mainline being available on i386 there are still cases where 4kB are not 
enough.

IMHO there seems to currently be a mismatch between it's maintainance 
cost and the actual number of users. That's in my opinion the main 
problem with it, no matter in which direction it gets resolved.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jamie Lokier]

Bernd Petrovitsch wrote:
> > 32MB no-MMU ARM boards which people run new things and attach new
> > devices to rather often - without making new hardware.  Volume's too
> > low per individual application to get new hardware designed and made.
> 
> Yes, you may have several products on the same hardware with somewhat
> differing requirements (or not). But that is much less than a general
> purpose system IMHO.

It is, but the idea that small embedded systems go through a 'all
components are known, drivers are known, test and if it passes it's
shippable' does not always apply.

> > I'm seriously thinking of forwarding porting the 4 year old firmware
> > from 2.4.26 to 2.6.current, just to get new drivers and capabilities.
> 
> That sounds reasonable (and I never meant maintaining the old system
> infinitely.

Sounds reasonable, but it's vetoed for anticipated time and cost,
compared with backporting on demand.  Fair enough, since 2.6.current
doesn't support ARM no-MMU last I heard ('soon'?).

On the other hand, the 2.6 anti-fragmentation patches, including
latest SLUB stuff, ironically meant to help big machines, sound really
appealing for my current problem and totally unrealistic to
backport...

> ACK. We avoid MMU-less hardware too - especially since there is enough
> hardware with a MMU around.

I can't emphasise enough how much difference MMU makes to Linux userspace.

It's practically: MMU = standard Linux (with less RAM), have everything.
No-MMU = lots of familiar 'Linux' things not available or break.

-- Jamie

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Bernd Petrovitsch]

On Mit, 2008-08-27 at 18:51 +0100, Jamie Lokier wrote:
> Bernd Petrovitsch wrote:
[...]
> It is, but the idea that small embedded systems go through a 'all
> components are known, drivers are known, test and if it passes it's
> shippable' does not always apply.

Not always but often enough. And yes, there is ARM-based embedded
hardware with 1GB Flash-RAM and 128MB RAM.

> > > I'm seriously thinking of forwarding porting the 4 year old firmware
> > > from 2.4.26 to 2.6.current, just to get new drivers and capabilities.
> > 
> > That sounds reasonable (and I never meant maintaining the old system
> > infinitely.
> 
> Sounds reasonable, but it's vetoed for anticipated time and cost,

That is to be expected;-)

[....]
> > ACK. We avoid MMU-less hardware too - especially since there is enough
> > hardware with a MMU around.
> 
> I can't emphasise enough how much difference MMU makes to Linux userspace.
> 
> It's practically: MMU = standard Linux (with less RAM), have everything.
> No-MMU = lots of familiar 'Linux' things not available or break.

ACK. And tell that a customer that everything is more effort and more
risk and not just "simply cross-compile it as it runs on my desktop
too".

	Bernd
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Peter Osterlund]

Linus Torvalds <torvalds@linux-foundation.org> writes:

> On Sat, 23 Aug 2008, Rafael J. Wysocki wrote:
>> 
>> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11401
>> Subject		: pktcdvd: BUG, NULL pointer dereference in pkt_ioctl, bisected
>> Submitter	: Laurent Riffard <laurent.riffard@free.fr>
>> Date		: 2008-08-22 08:16 (2 days old)
>
> This one looks irritating.
>
> It's bisected to 5b6155ee70e9c4d2ad7e6f514c8eee06e2711c3a ("pktcdvd: push 
> BKL down into driver"), but the problem goes deeper than that.
...
> Grr.
...
> Double grr.
...
> Hmm?
>
> We need to fix this.

Why not just revert the offending change and try again during the next
merge window, assuming someone has figured out an acceptable way to
handle this mess by then?

-- 
Peter Osterlund - petero2@telia.com
http://web.telia.com/~u89404340

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Wed, 27 Aug 2008, Peter Osterlund wrote:
> 
> Why not just revert the offending change and try again during the next
> merge window, assuming someone has figured out an acceptable way to
> handle this mess by then?

Well,, for 2.6.27 that's what we'll have to do. But there's actually a 
real problem here - the unlocked ioctl's (which we _should_ prefer) have a 
strictly weaker and worse interface. I also wonder if any other 
block_ioctl users were converted..

Anyway, I'll take your email as an ack for the revert.

		Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Wed, 27 Aug 2008, Linus Torvalds wrote:
>
> I also wonder if any other block_ioctl users were converted..

Well, doing

	git log -p v2.6.26.. -Sunlocked_ioctl

and looking for blkdev_ioctl, that does seem to be the only one. So 
hopefully no other case like this is lurking, although it is possible that 
non-block areas have similar issues.

			Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Alan Cox]

> >
> > We need to fix this.
> 
> Why not just revert the offending change and try again during the next
> merge window, assuming someone has figured out an acceptable way to
> handle this mess by then?

Easier just to fix it. Its a case of building everything until it
compiles with the prototype change. Almost all stuff  will just take the
argument initially and not use it.

Anyone else plan to do it or shall I hit all the x86 cases and post a
patch ?

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Alan Cox]

> Btw, why is unlocked_ioctl returning "long"? Does anybody depend on that 
> too? That's another difference between the "unlocked" and the traditional 
> version..

I don't know - a lot of syscall returns got defined as long and I guess
someone thought propogating the right type was a good diea ?
> 
> As to the "x86 cases", I think you should try to hit them all. Doing a 
> "git grep unlocked_ioctl" gets 185 entries, and it looks like only 
> something like 8 of them are non-x86 (3 in the arch/ directory, five in 
> s390 drivers).
> 
> Of course, some of them may be drivers that aren't available on x86 for 
> other reasons (ie the ARM embedded stuff), but regardless..
> 
> Anyway, the pure size of that patch makes me suspect that we might as well 
> leave it until the next merge window, but if you do it and it's obviously 
> totally mechanical, I'd be likely to just let it slip in early.

I'll take a crack at it tomorrow - but if its 185 entries then it
probably wants to go into -next instead.

Alan

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Wed, 27 Aug 2008, Alan Cox wrote:
> 
> Easier just to fix it. Its a case of building everything until it
> compiles with the prototype change. Almost all stuff  will just take the
> argument initially and not use it.
> 
> Anyone else plan to do it or shall I hit all the x86 cases and post a
> patch ?

Well, I alrady reverted it, but if you actually fix unlocked_ioctl() to 
have the same calling convention as regular ioctl() then a lot of the 
noise from ioctl conversion goes away, and all that remains is literally 
just the BKL part.

Btw, why is unlocked_ioctl returning "long"? Does anybody depend on that 
too? That's another difference between the "unlocked" and the traditional 
version..

As to the "x86 cases", I think you should try to hit them all. Doing a 
"git grep unlocked_ioctl" gets 185 entries, and it looks like only 
something like 8 of them are non-x86 (3 in the arch/ directory, five in 
s390 drivers).

Of course, some of them may be drivers that aren't available on x86 for 
other reasons (ie the ARM embedded stuff), but regardless..

Anyway, the pure size of that patch makes me suspect that we might as well 
leave it until the next merge window, but if you do it and it's obviously 
totally mechanical, I'd be likely to just let it slip in early.

		Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[David Miller]

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 27 Aug 2008 15:38:16 -0700 (PDT)

> Btw, why is unlocked_ioctl returning "long"? Does anybody depend on that 
> too? That's another difference between the "unlocked" and the traditional 
> version..

The return values want to be "long" sign extended all the way back
down to syscall dispatch, I think this is just an effort to add
some consistency here so that the int --> long extension eventually
can be eliminated once unlocked_ioctl is the only case left.

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Alexey Dobriyan]

On Wed, Aug 27, 2008 at 03:38:16PM -0700, Linus Torvalds wrote:
> On Wed, 27 Aug 2008, Alan Cox wrote:
> > 
> > Easier just to fix it. Its a case of building everything until it
> > compiles with the prototype change. Almost all stuff  will just take the
> > argument initially and not use it.
> > 
> > Anyone else plan to do it or shall I hit all the x86 cases and post a
> > patch ?
> 
> Well, I alrady reverted it, but if you actually fix unlocked_ioctl() to 
> have the same calling convention as regular ioctl() then a lot of the 
> noise from ioctl conversion goes away, and all that remains is literally 
> just the BKL part.
> 
> Btw, why is unlocked_ioctl returning "long"? Does anybody depend on that 
> too? That's another difference between the "unlocked" and the traditional 
> version..
> 
> As to the "x86 cases", I think you should try to hit them all. Doing a 
> "git grep unlocked_ioctl" gets 185 entries, and it looks like only 
> something like 8 of them are non-x86 (3 in the arch/ directory, five in 
> s390 drivers).
> 
> Of course, some of them may be drivers that aren't available on x86 for 
> other reasons (ie the ARM embedded stuff), but regardless..
> 
> Anyway, the pure size of that patch makes me suspect that we might as well 
> leave it until the next merge window, but if you do it and it's obviously 
> totally mechanical, I'd be likely to just let it slip in early.

Anybody doing this, don't forget to actually use "inode" instead of all those
dereferences:

	struct inode *inode = filp->f_path.dentry->d_inode;

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Wed, 27 Aug 2008, Alan Cox wrote:
> 
> I'll take a crack at it tomorrow - but if its 185 entries then it
> probably wants to go into -next instead.

Being more careful.. This:

	git grep 'unlocked_ioctl.*=' |
		sed 's/^.*=[ 	]*\([_a-zA-Z0-9]*\).*$/\1/' |
		uniq | wc

says that ther are 160 distinct cases. I'm not sure it catches everything 
exactly, but it will be reasonably close, at least.

I wonder if I could essentially automate something to do the conversion..

		Linus

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Wed, 27 Aug 2008, Linus Torvalds wrote:
> 
> I wonder if I could essentially automate something to do the conversion..

Hmm. compat_ioctl() actually has exactly the same issue. Damn.

So you can't just add the new argument, you also have to _pass_ the 
argument in the compat_ioctl handlers to the non-compat ones.

		Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Greg Ungerer]

Jamie Lokier wrote:
> Bernd Petrovitsch wrote:
>>> 32MB no-MMU ARM boards which people run new things and attach new
>>> devices to rather often - without making new hardware.  Volume's too
>>> low per individual application to get new hardware designed and made.
>> Yes, you may have several products on the same hardware with somewhat
>> differing requirements (or not). But that is much less than a general
>> purpose system IMHO.
> 
> It is, but the idea that small embedded systems go through a 'all
> components are known, drivers are known, test and if it passes it's
> shippable' does not always apply.
> 
>>> I'm seriously thinking of forwarding porting the 4 year old firmware
>>> from 2.4.26 to 2.6.current, just to get new drivers and capabilities.
>> That sounds reasonable (and I never meant maintaining the old system
>> infinitely.
> 
> Sounds reasonable, but it's vetoed for anticipated time and cost,
> compared with backporting on demand.  Fair enough, since 2.6.current
> doesn't support ARM no-MMU last I heard ('soon'?).
> 
> On the other hand, the 2.6 anti-fragmentation patches, including
> latest SLUB stuff, ironically meant to help big machines, sound really
> appealing for my current problem and totally unrealistic to
> backport...
> 
>> ACK. We avoid MMU-less hardware too - especially since there is enough
>> hardware with a MMU around.
> 
> I can't emphasise enough how much difference MMU makes to Linux userspace.
> 
> It's practically: MMU = standard Linux (with less RAM), have everything.
> No-MMU = lots of familiar 'Linux' things not available or break.

And lots of things work in the usual way...

Of course the flip side is that for people who have platforms
without MMU they can run something more than the mostly "toy"
like operating systems typically available. There are plenty of
problem domains that the non-MMU limitations are not a problem for.
(Yours doesn't sound like one of them :-)

Regards
Greg


------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
Secure Computing Corporation                PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Greg Ungerer]

Jamie Lokier wrote:
> Bernd Petrovitsch wrote:
>> If you "develop" an embedded system (which is partly system integration
>> of existing apps) to be installed in the field, you don't have that many
>> conceivable work loads compared to a desktop/server system. And you have
>> a fixed list of drivers and applications.
> 
> Hah!  Not in my line of embedded device.
> 
> 32MB no-MMU ARM boards which people run new things and attach new
> devices to rather often - without making new hardware.  Volume's too
> low per individual application to get new hardware designed and made.
> 
> I'm seriously thinking of forwarding porting the 4 year old firmware
> from 2.4.26 to 2.6.current, just to get new drivers and capabilities.
> Backporting is tedious, so's feeling wretchedly far from the mainline
> world.
> 
>> A usual approach is to run stress tests on several (or all)
>> subsystems/services/... in parallel and if the device survives it
>> functioning correctly, it is at least good enough.
> 
> Per application.
> 
> Some little devices run hundreds of different applications and
> customers expect to customise, script themselves, and attach different
> devices (over USB).  The next customer in the chain expects the bits
> you supplied to work in a variety of unexpected situations, even when
> you advise that it probably won't do that.
> 
> Much like desktop/server Linux, but on a small device where silly
> little things like 'create a process' are a stress for the dear little
> thing.
> 
> (My biggest lesson: insist on an MMU next time!)

But given you have hardware you can't change would you choose
to not run Linux, even with the limitations of non-MMU?

Hell no :-)

Regards
Greg


------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
Secure Computing Corporation                PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Paul Mundt]

On Wed, Aug 27, 2008 at 08:35:44PM +0300, Adrian Bunk wrote:
> On Thu, Aug 28, 2008 at 01:00:52AM +0900, Paul Mundt wrote:
> > On Wed, Aug 27, 2008 at 02:58:30PM +0300, Adrian Bunk wrote:
> > In addition to that, debugging the runaway stack users on 4k tends to be
> > easier anyways since you end up blowing the stack a lot sooner. On sh
> > we've had pretty good luck with it, though most of our users are using
> > fairly deterministic workloads and continually profiling the footprint.
> > Anything that runs away or uses an insane amount of stack space needs to
> > be fixed well before that anyways, so catching it sooner is always
> > preferable. I imagine the same case is true for m68knommu (even sans IRQ
> > stacks).
> 
> CONFIG_DEBUG_STACKOVERFLOW should give you the same information, and if
> wanted with an arbitrary limit.
> 
In some cases, yes. In the CONFIG_DEBUG_STACKOVERFLOW case the check is
only performed from do_IRQ(), which is sporadic at best, especially on
tickless. While it catches some things, it's not a complete solution in
and of iteslf.

In addition to this, there are even fewer platforms that support it than
there are platforms that do 4k stacks. At first glance, it looks like
it's only m32r, powerpc, sh, x86, and xtensa. Others support the Kconfig
option, but don't seem to realize that it's not an option that the kernel
does anything with by itself, and so don't actually do anything (ie,
FRV).

> > Things might be more sensitive on x86, but it's certainly not something
> > that's a huge problem for the various embedded platforms to wire up,
> > whether they want to go the IRQ stack route or not.
> 
> How many platforms use 4kB stacks on sh?
> 
> Only 1 out of 34 defconfigs uses it.
> 
The defconfigs tend to enable as much random stuff as people are
interested in for development and testing purposes. Most of these end up
being reference boards and are the basis for products, rather than
shipping products themselves. In the latter case, everything is gradually
tightened down, and 4k stack utilization in that case is the norm, rather
than the exception.

> > In any event, lack of support for something on embedded architectures in
> > the kernel is more often due to apathy/utter indifference on the part of
> > the architecture maintainer rather than being indicative of any intrinsic
> > difficulty in supporting the thing in question. Most new "features" on the
> > lesser maintained architectures tend to end up there either out of peer
> > pressure or copying-and-pasting accidents rather than any sort of design.
> > ;-)
> 
> arm or powerpc aren't exactly lesser maintained architectures.
> 
Indeed, which is why I find it bizarre that you would even bother
applying what was said to those platforms. Specifically I was referring
to the embedded platforms that don't do 4k stacks today. The fact they
don't support them today has much less to do with 4k being an
unattainable limit as it does with people simply not bothering to
implement it on their platform.

> IMHO there seems to currently be a mismatch between it's maintainance 
> cost and the actual number of users. That's in my opinion the main 
> problem with it, no matter in which direction it gets resolved.
> 
Perhaps that's true on x86, but in general I take issue with that. On sh
we've had to do very little maintenance for it and most shipping products
are using it today (at least on MMU-Linux, we don't bother with it on
nommu). Most of the problems we ran in to with 4k stacks tended to be
stuff that we wanted to fix for 8k anyways. I suspect that this case is
true for the other embedded platforms also.

Note that on sh we also conditionalize IRQ stacks separately, so while
they are often used together, it's possible to use 4k stacks without
resorting to IRQ stacks (as m68knommu also seems to do).

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Linus Torvalds]

On Wed, 27 Aug 2008, Linus Torvalds wrote:
> 
> Hmm. compat_ioctl() actually has exactly the same issue. Damn.
> 
> So you can't just add the new argument, you also have to _pass_ the 
> argument in the compat_ioctl handlers to the non-compat ones.

What the hell. Here's a test patch. A largish part of it was generated 
through a stupid script that basically did a number of grep + 'sed' on a 
lot of files, and then the rest was fixed up manually after running "make 
allmodconfig".

I'm not going to guarantee anything, but it gets close. A starting point 
for somebody else, and considering that it is

 208 files changed, 370 insertions(+), 376 deletions(-)

this is definitely linux-next material.

The extra deletions are mainly because the passing of "inode" as an 
argument means that some functions don't need to look it up manually any 
more.

And yeah, I changed the return type to "int". There's no way the kernel 
can validly return anything bigger than that anyway. And this way all the 
ioctl functions have the same type, no confusion.

TOTALLY UNTESTED apart from the fact that it compiles.

			Linus

---
 arch/mips/sibyte/common/sb_tbprof.c   |    2 +-
 arch/parisc/kernel/perf.c             |    4 +-
 arch/sparc/kernel/apc.c               |    2 +-
 arch/x86/kernel/apm_32.c              |    2 +-
 arch/x86/kernel/cpu/mcheck/mce_64.c   |    2 +-
 arch/x86/kernel/cpu/mtrr/if.c         |    3 +-
 block/bsg.c                           |    2 +-
 block/compat_ioctl.c                  |   18 +++++++++++-----
 block/ioctl.c                         |    3 +-
 drivers/block/DAC960.c                |    2 +-
 drivers/block/cciss.c                 |    4 +-
 drivers/block/loop.c                  |    3 +-
 drivers/block/paride/pt.c             |    4 +-
 drivers/char/agp/agp.h                |    2 +-
 drivers/char/agp/compat_ioctl.c       |    2 +-
 drivers/char/agp/frontend.c           |    2 +-
 drivers/char/ds1302.c                 |    2 +-
 drivers/char/dsp56k.c                 |    2 +-
 drivers/char/efirtc.c                 |    4 +-
 drivers/char/ip2/ip2main.c            |    6 ++--
 drivers/char/ip27-rtc.c               |    4 +-
 drivers/char/ipmi/ipmi_devintf.c      |    2 +-
 drivers/char/mmtimer.c                |    4 +-
 drivers/char/mwave/mwavedd.c          |    4 +-
 drivers/char/pcmcia/cm4000_cs.c       |    3 +-
 drivers/char/ppdev.c                  |    2 +-
 drivers/char/random.c                 |    2 +-
 drivers/char/rio/rio_linux.c          |    4 +-
 drivers/char/rtc.c                    |    4 +-
 drivers/char/sx.c                     |    4 +-
 drivers/char/tty_io.c                 |   14 +++++-------
 drivers/char/viotape.c                |    2 +-
 drivers/firewire/fw-cdev.c            |    8 +++---
 drivers/gpu/drm/i915/i915_drv.h       |    2 +-
 drivers/gpu/drm/i915/i915_ioc32.c     |    2 +-
 drivers/gpu/drm/mga/mga_drv.h         |    2 +-
 drivers/gpu/drm/mga/mga_ioc32.c       |    2 +-
 drivers/gpu/drm/r128/r128_drv.h       |    2 +-
 drivers/gpu/drm/r128/r128_ioc32.c     |    2 +-
 drivers/gpu/drm/radeon/radeon_drv.h   |    2 +-
 drivers/gpu/drm/radeon/radeon_ioc32.c |    2 +-
 drivers/hid/hidraw.c                  |    3 +-
 drivers/hid/usbhid/hiddev.c           |    6 ++--
 drivers/i2c/i2c-dev.c                 |    2 +-
 drivers/ieee1394/dv1394.c             |   20 +++++++++---------
 drivers/ieee1394/raw1394.c            |    4 +-
 drivers/ieee1394/video1394.c          |   34 ++++++++++++++++----------------
 drivers/infiniband/core/user_mad.c    |    4 +-
 drivers/input/evdev.c                 |    4 +-
 drivers/input/joydev.c                |    4 +-
 drivers/input/misc/uinput.c           |    2 +-
 drivers/md/dm-ioctl.c                 |    6 ++--
 drivers/media/video/compat_ioctl32.c  |   26 ++++++++++++------------
 drivers/message/fusion/mptctl.c       |    8 +++---
 drivers/message/i2o/i2o_config.c      |    2 +-
 drivers/misc/phantom.c                |    6 ++--
 drivers/misc/sgi-gru/grufile.c        |    2 +-
 drivers/net/ppp_generic.c             |    2 +-
 drivers/pci/proc.c                    |    2 +-
 drivers/rtc/rtc-dev.c                 |    2 +-
 drivers/s390/block/dasd_int.h         |    2 +-
 drivers/s390/char/tape_char.c         |    2 +-
 drivers/s390/char/vmcp.c              |    2 +-
 drivers/s390/cio/chsc_sch.c           |    2 +-
 drivers/s390/crypto/zcrypt_api.c      |    4 +-
 drivers/s390/scsi/zfcp_cfdc.c         |    2 +-
 drivers/sbus/char/cpwatchdog.c        |    2 +-
 drivers/sbus/char/display7seg.c       |    2 +-
 drivers/sbus/char/openprom.c          |    2 +-
 drivers/scsi/aacraid/linit.c          |    2 +-
 drivers/scsi/ch.c                     |    6 ++--
 drivers/scsi/dpt_i2o.c                |    7 +----
 drivers/scsi/megaraid/megaraid_mm.c   |   10 ++++----
 drivers/scsi/megaraid/megaraid_sas.c  |   10 ++++----
 drivers/scsi/osst.c                   |    2 +-
 drivers/scsi/sd.c                     |    2 +-
 drivers/scsi/sg.c                     |    2 +-
 drivers/scsi/st.c                     |    4 +-
 drivers/spi/spidev.c                  |    4 +-
 drivers/telephony/ixj.c               |    2 +-
 drivers/usb/class/usblp.c             |    2 +-
 drivers/usb/gadget/inode.c            |    6 ++--
 drivers/usb/gadget/printer.c          |    4 +-
 drivers/usb/misc/iowarrior.c          |    2 +-
 drivers/usb/misc/rio500.c             |    2 +-
 drivers/usb/misc/sisusbvga/sisusb.c   |   10 ++++----
 drivers/usb/misc/usblcd.c             |    2 +-
 drivers/video/fbmem.c                 |    4 +--
 drivers/watchdog/acquirewdt.c         |    2 +-
 drivers/watchdog/advantechwdt.c       |    2 +-
 drivers/watchdog/alim1535_wdt.c       |    2 +-
 drivers/watchdog/alim7101_wdt.c       |    2 +-
 drivers/watchdog/ar7_wdt.c            |    2 +-
 drivers/watchdog/at32ap700x_wdt.c     |    2 +-
 drivers/watchdog/at91rm9200_wdt.c     |    2 +-
 drivers/watchdog/bfin_wdt.c           |    2 +-
 drivers/watchdog/booke_wdt.c          |    2 +-
 drivers/watchdog/cpu5wdt.c            |    2 +-
 drivers/watchdog/davinci_wdt.c        |    2 +-
 drivers/watchdog/ep93xx_wdt.c         |    2 +-
 drivers/watchdog/eurotechwdt.c        |    2 +-
 drivers/watchdog/hpwdt.c              |    2 +-
 drivers/watchdog/i6300esb.c           |    2 +-
 drivers/watchdog/iTCO_wdt.c           |    2 +-
 drivers/watchdog/ib700wdt.c           |    2 +-
 drivers/watchdog/ibmasr.c             |    2 +-
 drivers/watchdog/indydog.c            |    2 +-
 drivers/watchdog/iop_wdt.c            |    2 +-
 drivers/watchdog/it8712f_wdt.c        |    2 +-
 drivers/watchdog/ixp2000_wdt.c        |    2 +-
 drivers/watchdog/ixp4xx_wdt.c         |    2 +-
 drivers/watchdog/ks8695_wdt.c         |    2 +-
 drivers/watchdog/machzwd.c            |    2 +-
 drivers/watchdog/mixcomwd.c           |    2 +-
 drivers/watchdog/mpc5200_wdt.c        |    2 +-
 drivers/watchdog/mpc8xxx_wdt.c        |    2 +-
 drivers/watchdog/mpcore_wdt.c         |    2 +-
 drivers/watchdog/mtx-1_wdt.c          |    2 +-
 drivers/watchdog/mv64x60_wdt.c        |    2 +-
 drivers/watchdog/omap_wdt.c           |    2 +-
 drivers/watchdog/pc87413_wdt.c        |    2 +-
 drivers/watchdog/pcwd.c               |    2 +-
 drivers/watchdog/pcwd_pci.c           |    2 +-
 drivers/watchdog/pcwd_usb.c           |    2 +-
 drivers/watchdog/pnx4008_wdt.c        |    2 +-
 drivers/watchdog/rm9k_wdt.c           |    4 +-
 drivers/watchdog/s3c2410_wdt.c        |    2 +-
 drivers/watchdog/sa1100_wdt.c         |    2 +-
 drivers/watchdog/sb_wdog.c            |    2 +-
 drivers/watchdog/sbc60xxwdt.c         |    2 +-
 drivers/watchdog/sbc7240_wdt.c        |    2 +-
 drivers/watchdog/sbc_epx_c3.c         |    2 +-
 drivers/watchdog/sc1200wdt.c          |    2 +-
 drivers/watchdog/sc520_wdt.c          |    2 +-
 drivers/watchdog/scx200_wdt.c         |    2 +-
 drivers/watchdog/shwdt.c              |    2 +-
 drivers/watchdog/smsc37b787_wdt.c     |    2 +-
 drivers/watchdog/softdog.c            |    2 +-
 drivers/watchdog/txx9wdt.c            |    2 +-
 drivers/watchdog/w83627hf_wdt.c       |    2 +-
 drivers/watchdog/w83697hf_wdt.c       |    2 +-
 drivers/watchdog/w83877f_wdt.c        |    2 +-
 drivers/watchdog/w83977f_wdt.c        |    2 +-
 drivers/watchdog/wafer5823wdt.c       |    2 +-
 drivers/watchdog/wdrtas.c             |    2 +-
 drivers/watchdog/wdt.c                |    2 +-
 drivers/watchdog/wdt285.c             |    2 +-
 drivers/watchdog/wdt977.c             |    2 +-
 drivers/watchdog/wdt_pci.c            |    2 +-
 fs/bad_inode.c                        |    4 +-
 fs/block_dev.c                        |    7 +++++-
 fs/cifs/cifsfs.h                      |    2 +-
 fs/cifs/ioctl.c                       |    3 +-
 fs/compat_ioctl.c                     |    3 +-
 fs/ext2/ext2.h                        |    4 +-
 fs/ext2/ioctl.c                       |    7 ++---
 fs/ext3/ioctl.c                       |    3 +-
 fs/ext4/ext4.h                        |    4 +-
 fs/ext4/ioctl.c                       |    7 ++---
 fs/fat/dir.c                          |    3 +-
 fs/gfs2/ops_file.c                    |    2 +-
 fs/inotify_user.c                     |    2 +-
 fs/ioctl.c                            |    8 +++---
 fs/jffs2/ioctl.c                      |    2 +-
 fs/jffs2/os-linux.h                   |    2 +-
 fs/jfs/ioctl.c                        |    7 ++---
 fs/jfs/jfs_inode.h                    |    4 +-
 fs/ncpfs/ioctl.c                      |    3 +-
 fs/ocfs2/ioctl.c                      |    7 ++---
 fs/ocfs2/ioctl.h                      |    4 +-
 fs/pipe.c                             |    3 +-
 fs/proc/inode.c                       |   14 ++++++------
 fs/reiserfs/ioctl.c                   |    3 +-
 fs/ubifs/ioctl.c                      |    7 ++---
 fs/ubifs/ubifs.h                      |    4 +-
 fs/xfs/linux-2.6/xfs_file.c           |    8 +++---
 fs/xfs/linux-2.6/xfs_ioctl32.c        |    6 +++-
 fs/xfs/linux-2.6/xfs_ioctl32.h        |    4 +-
 include/linux/ext3_fs.h               |    2 +-
 include/linux/fs.h                    |   10 ++++----
 include/linux/ncp_fs.h                |    2 +-
 include/linux/reiserfs_fs.h           |    2 +-
 include/linux/tty.h                   |    2 +-
 include/linux/wanrouter.h             |    2 +-
 include/media/v4l2-ioctl.h            |    2 +-
 kernel/power/user.c                   |    2 +-
 net/irda/irnet/irnet_ppp.c            |    3 +-
 net/irda/irnet/irnet_ppp.h            |    5 ++-
 net/socket.c                          |    8 +++---
 net/wanrouter/wanmain.c               |    3 +-
 sound/core/control.c                  |    2 +-
 sound/core/control_compat.c           |    4 +-
 sound/core/hwdep.c                    |    2 +-
 sound/core/hwdep_compat.c             |    4 +-
 sound/core/info.c                     |    2 +-
 sound/core/init.c                     |    2 +-
 sound/core/oss/mixer_oss.c            |    2 +-
 sound/core/oss/pcm_oss.c              |    2 +-
 sound/core/pcm_compat.c               |    2 +-
 sound/core/pcm_native.c               |    4 +-
 sound/core/rawmidi.c                  |    2 +-
 sound/core/rawmidi_compat.c           |    4 +-
 sound/core/seq/oss/seq_oss.c          |    6 ++--
 sound/core/seq/seq_clientmgr.c        |    2 +-
 sound/core/seq/seq_compat.c           |    2 +-
 sound/core/timer.c                    |    2 +-
 sound/core/timer_compat.c             |    4 +-
 virt/kvm/kvm_main.c                   |    8 +++---
 208 files changed, 370 insertions(+), 376 deletions(-)

diff --git a/arch/mips/sibyte/common/sb_tbprof.c b/arch/mips/sibyte/common/sb_tbprof.c
index 66e3e3f..5419f85 100644
--- a/arch/mips/sibyte/common/sb_tbprof.c
+++ b/arch/mips/sibyte/common/sb_tbprof.c
@@ -507,7 +507,7 @@ static ssize_t sbprof_tb_read(struct file *filp, char *buf,
 	return count;
 }
 
-static long sbprof_tb_ioctl(struct file *filp,
+static int sbprof_tb_ioctl(struct inode *inode, struct file *filp,
 			    unsigned int command,
 			    unsigned long arg)
 {
diff --git a/arch/parisc/kernel/perf.c b/arch/parisc/kernel/perf.c
index f696f57..6d98acc 100644
--- a/arch/parisc/kernel/perf.c
+++ b/arch/parisc/kernel/perf.c
@@ -198,7 +198,7 @@ static int perf_open(struct inode *inode, struct file *file);
 static ssize_t perf_read(struct file *file, char __user *buf, size_t cnt, loff_t *ppos);
 static ssize_t perf_write(struct file *file, const char __user *buf, size_t count, 
 	loff_t *ppos);
-static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+static int perf_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 static void perf_start_counters(void);
 static int perf_stop_counters(uint32_t *raddr);
 static const struct rdr_tbl_ent * perf_rdr_get_entry(uint32_t rdr_num);
@@ -442,7 +442,7 @@ static void perf_patch_images(void)
  * must be running on the processor that you wish to change.
  */
 
-static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int perf_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	long error_start;
 	uint32_t raddr[4];
diff --git a/arch/sparc/kernel/apc.c b/arch/sparc/kernel/apc.c
index 5267d48..d49a35a 100644
--- a/arch/sparc/kernel/apc.c
+++ b/arch/sparc/kernel/apc.c
@@ -85,7 +85,7 @@ static int apc_release(struct inode *inode, struct file *f)
 	return 0;
 }
 
-static long apc_ioctl(struct file *f, unsigned int cmd, unsigned long __arg)
+static int apc_ioctl(struct inode *inode, struct file *f, unsigned int cmd, unsigned long __arg)
 {
 	__u8 inarg, __user *arg;
 
diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index 9ee24e6..329e4c5 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -1460,7 +1460,7 @@ static unsigned int do_poll(struct file *fp, poll_table *wait)
 	return 0;
 }
 
-static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
+static int do_ioctl(struct inode *inode, struct file *filp, u_int cmd, u_long arg)
 {
 	struct apm_user *as;
 	int ret;
diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c
index 726a5fc..91f970f 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -645,7 +645,7 @@ static unsigned int mce_poll(struct file *file, poll_table *wait)
 	return 0;
 }
 
-static long mce_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+static int mce_ioctl(struct inode *inode, struct file *f, unsigned int cmd, unsigned long arg)
 {
 	int __user *p = (int __user *)arg;
 
diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c
index 84c480b..d6b053b 100644
--- a/arch/x86/kernel/cpu/mtrr/if.c
+++ b/arch/x86/kernel/cpu/mtrr/if.c
@@ -145,8 +145,7 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos)
 	return -EINVAL;
 }
 
-static long
-mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
+static int mtrr_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long __arg)
 {
 	int err = 0;
 	mtrr_type type;
diff --git a/block/bsg.c b/block/bsg.c
index 0aae8d7..1ec2e02 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -872,7 +872,7 @@ static unsigned int bsg_poll(struct file *file, poll_table *wait)
 	return mask;
 }
 
-static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int bsg_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct bsg_device *bd = file->private_data;
 	int __user *uarg = (int __user *) arg;
diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index c23177e..2c32818 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -709,7 +709,7 @@ static int compat_blkdev_driver_ioctl(struct inode *inode, struct file *file,
 	}
 
 	if (disk->fops->unlocked_ioctl)
-		return disk->fops->unlocked_ioctl(file, cmd, arg);
+		return disk->fops->unlocked_ioctl(inode, file, cmd, arg);
 
 	if (disk->fops->ioctl) {
 		lock_kernel();
@@ -773,10 +773,16 @@ static int compat_blkdev_locked_ioctl(struct inode *inode, struct file *file,
 	return -ENOIOCTLCMD;
 }
 
-/* Most of the generic ioctls are handled in the normal fallback path.
-   This assumes the blkdev's low level compat_ioctl always returns
-   ENOIOCTLCMD for unknown ioctls. */
-long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+/*
+ * Most of the generic ioctls are handled in the normal fallback path.
+ * This assumes the blkdev's low level compat_ioctl always returns
+ * ENOIOCTLCMD for unknown ioctls.
+ *
+ * NOTE! We ignore the on-disk inode that was passed as
+ * an argument, and use the "f_mapping->host" inode for
+ * all block ioctls!
+ */
+int compat_blkdev_ioctl(struct inode *unused, struct file *file, unsigned cmd, unsigned long arg)
 {
 	int ret = -ENOIOCTLCMD;
 	struct inode *inode = file->f_mapping->host;
@@ -806,7 +812,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 	ret = compat_blkdev_locked_ioctl(inode, file, bdev, cmd, arg);
 	/* FIXME: why do we assume -> compat_ioctl needs the BKL? */
 	if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
-		ret = disk->fops->compat_ioctl(file, cmd, arg);
+		ret = disk->fops->compat_ioctl(inode, file, cmd, arg);
 	unlock_kernel();
 
 	if (ret != -ENOIOCTLCMD)
diff --git a/block/ioctl.c b/block/ioctl.c
index 77185e5..a85824e 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -204,8 +204,9 @@ int blkdev_driver_ioctl(struct inode *inode, struct file *file,
 			struct gendisk *disk, unsigned cmd, unsigned long arg)
 {
 	int ret;
+
 	if (disk->fops->unlocked_ioctl)
-		return disk->fops->unlocked_ioctl(file, cmd, arg);
+		return disk->fops->unlocked_ioctl(inode, file, cmd, arg);
 
 	if (disk->fops->ioctl) {
 		lock_kernel();
diff --git a/drivers/block/DAC960.c b/drivers/block/DAC960.c
index a002a38..972539d 100644
--- a/drivers/block/DAC960.c
+++ b/drivers/block/DAC960.c
@@ -6628,7 +6628,7 @@ static void DAC960_DestroyProcEntries(DAC960_Controller_T *Controller)
  * DAC960_gam_ioctl is the ioctl function for performing RAID operations.
 */
 
-static long DAC960_gam_ioctl(struct file *file, unsigned int Request,
+static int DAC960_gam_ioctl(struct inode *inode, struct file *file, unsigned int Request,
 						unsigned long Argument)
 {
   long ErrorCode = 0;
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index b73116e..67404dd 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -192,7 +192,7 @@ static void cciss_procinit(int i)
 #endif				/* CONFIG_PROC_FS */
 
 #ifdef CONFIG_COMPAT
-static long cciss_compat_ioctl(struct file *f, unsigned cmd, unsigned long arg);
+static int cciss_compat_ioctl(struct inode *inode, struct file *f, unsigned cmd, unsigned long arg);
 #endif
 
 static struct block_device_operations cciss_fops = {
@@ -618,7 +618,7 @@ static int cciss_ioctl32_passthru(struct file *f, unsigned cmd,
 static int cciss_ioctl32_big_passthru(struct file *f, unsigned cmd,
 				      unsigned long arg);
 
-static long cciss_compat_ioctl(struct file *f, unsigned cmd, unsigned long arg)
+static int cciss_compat_ioctl(struct inode *inode, struct file *f, unsigned cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case CCISS_GETPCIINFO:
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index d3a25b0..bfa4f44 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1292,9 +1292,8 @@ loop_get_status_compat(struct loop_device *lo,
 	return err;
 }
 
-static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int lo_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	struct loop_device *lo = inode->i_bdev->bd_disk->private_data;
 	int err;
 
diff --git a/drivers/block/paride/pt.c b/drivers/block/paride/pt.c
index 673b8b2..5a6fe4a 100644
--- a/drivers/block/paride/pt.c
+++ b/drivers/block/paride/pt.c
@@ -190,7 +190,7 @@ module_param_array(drive3, int, NULL, 0);
 #define ATAPI_LOG_SENSE		0x4d
 
 static int pt_open(struct inode *inode, struct file *file);
-static long pt_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+static int pt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 static int pt_release(struct inode *inode, struct file *file);
 static ssize_t pt_read(struct file *filp, char __user *buf,
 		       size_t count, loff_t * ppos);
@@ -690,7 +690,7 @@ out:
 	return err;
 }
 
-static long pt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int pt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct pt_unit *tape = file->private_data;
 	struct mtop __user *p = (void __user *)arg;
diff --git a/drivers/char/agp/agp.h b/drivers/char/agp/agp.h
index 4bada0e..acdeee0 100644
--- a/drivers/char/agp/agp.h
+++ b/drivers/char/agp/agp.h
@@ -313,7 +313,7 @@ extern const struct aper_size_info_16 agp3_generic_sizes[];
 extern int agp_off;
 extern int agp_try_unsupported_boot;
 
-long compat_agp_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+int compat_agp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 
 /* Chipset independant registers (from AGP Spec) */
 #define AGP_APBASE	0x10
diff --git a/drivers/char/agp/compat_ioctl.c b/drivers/char/agp/compat_ioctl.c
index 58c57cb..abd8974 100644
--- a/drivers/char/agp/compat_ioctl.c
+++ b/drivers/char/agp/compat_ioctl.c
@@ -202,7 +202,7 @@ static int compat_agpioc_unbind_wrap(struct agp_file_private *priv, void __user
 	return agp_unbind_memory(memory);
 }
 
-long compat_agp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int compat_agp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct agp_file_private *curr_priv = file->private_data;
 	int ret_val = -ENOTTY;
diff --git a/drivers/char/agp/frontend.c b/drivers/char/agp/frontend.c
index a96f319..0a2d134 100644
--- a/drivers/char/agp/frontend.c
+++ b/drivers/char/agp/frontend.c
@@ -971,7 +971,7 @@ int agpioc_chipset_flush_wrap(struct agp_file_private *priv)
 	return 0;
 }
 
-static long agp_ioctl(struct file *file,
+static int agp_ioctl(struct inode *inode, struct file *file,
 		     unsigned int cmd, unsigned long arg)
 {
 	struct agp_file_private *curr_priv = file->private_data;
diff --git a/drivers/char/ds1302.c b/drivers/char/ds1302.c
index c5e67a6..95aac80 100644
--- a/drivers/char/ds1302.c
+++ b/drivers/char/ds1302.c
@@ -154,7 +154,7 @@ static unsigned char days_in_mo[] =
 
 /* ioctl that supports RTC_RD_TIME and RTC_SET_TIME (read and set time/date). */
 
-static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	unsigned long flags;
 
diff --git a/drivers/char/dsp56k.c b/drivers/char/dsp56k.c
index ca7c72a..e4866bc 100644
--- a/drivers/char/dsp56k.c
+++ b/drivers/char/dsp56k.c
@@ -303,7 +303,7 @@ static ssize_t dsp56k_write(struct file *file, const char __user *buf, size_t co
 	}
 }
 
-static long dsp56k_ioctl(struct file *file, unsigned int cmd,
+static int dsp56k_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 			 unsigned long arg)
 {
 	int dev = iminor(file->f_path.dentry->d_inode) & 0x0f;
diff --git a/drivers/char/efirtc.c b/drivers/char/efirtc.c
index 34d15d5..3131dc0 100644
--- a/drivers/char/efirtc.c
+++ b/drivers/char/efirtc.c
@@ -51,7 +51,7 @@
 
 static DEFINE_SPINLOCK(efi_rtc_lock);
 
-static long efi_rtc_ioctl(struct file *file, unsigned int cmd,
+static int efi_rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg);
 
 #define is_leap(year) \
@@ -146,7 +146,7 @@ convert_from_efi_time(efi_time_t *eft, struct rtc_time *wtime)
 	}
 }
 
-static long efi_rtc_ioctl(struct file *file, unsigned int cmd,
+static int efi_rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 
diff --git a/drivers/char/ip2/ip2main.c b/drivers/char/ip2/ip2main.c
index 689f9dc..5ac4c8d 100644
--- a/drivers/char/ip2/ip2main.c
+++ b/drivers/char/ip2/ip2main.c
@@ -203,7 +203,7 @@ static int set_serial_info(i2ChanStrPtr, struct serial_struct __user *);
 
 static ssize_t ip2_ipl_read(struct file *, char __user *, size_t, loff_t *);
 static ssize_t ip2_ipl_write(struct file *, const char __user *, size_t, loff_t *);
-static long ip2_ipl_ioctl(struct file *, UINT, ULONG);
+static int ip2_ipl_ioctl(struct inode *inode, struct file *, UINT, ULONG);
 static int ip2_ipl_open(struct inode *, struct file *);
 
 static int DumpTraceBuffer(char __user *, int);
@@ -2845,8 +2845,8 @@ ip2_ipl_write(struct file *pFile, const char __user *pData, size_t count, loff_t
 /*                                                                            */
 /*                                                                            */
 /******************************************************************************/
-static long
-ip2_ipl_ioctl (struct file *pFile, UINT cmd, ULONG arg )
+static int
+ip2_ipl_ioctl(struct inode *inode, struct file *pFile, UINT cmd, ULONG arg )
 {
 	unsigned int iplminor = iminor(pFile->f_path.dentry->d_inode);
 	int rc = 0;
diff --git a/drivers/char/ip27-rtc.c b/drivers/char/ip27-rtc.c
index ec9d044..f85a353 100644
--- a/drivers/char/ip27-rtc.c
+++ b/drivers/char/ip27-rtc.c
@@ -47,7 +47,7 @@
 #include <asm/sn/sn0/hub.h>
 #include <asm/sn/sn_private.h>
 
-static long rtc_ioctl(struct file *filp, unsigned int cmd,
+static int rtc_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 			unsigned long arg);
 
 static int rtc_read_proc(char *page, char **start, off_t off,
@@ -76,7 +76,7 @@ static unsigned long epoch = 1970;	/* year corresponding to 0x00	*/
 static const unsigned char days_in_mo[] =
 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
 
-static long rtc_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int rtc_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 
 	struct rtc_time wtime;
diff --git a/drivers/char/ipmi/ipmi_devintf.c b/drivers/char/ipmi/ipmi_devintf.c
index 64e1c16..02a8511 100644
--- a/drivers/char/ipmi/ipmi_devintf.c
+++ b/drivers/char/ipmi/ipmi_devintf.c
@@ -762,7 +762,7 @@ static long put_compat_ipmi_recv(struct ipmi_recv *p64,
 /*
  * Handle compatibility ioctls
  */
-static long compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
+static int compat_ipmi_ioctl(struct inode *inode, struct file *filep, unsigned int cmd,
 			      unsigned long arg)
 {
 	int rc;
diff --git a/drivers/char/mmtimer.c b/drivers/char/mmtimer.c
index 918711a..e2b2463 100644
--- a/drivers/char/mmtimer.c
+++ b/drivers/char/mmtimer.c
@@ -58,7 +58,7 @@ extern unsigned long sn_rtc_cycles_per_second;
 
 #define rtc_time()              (*RTC_COUNTER_ADDR)
 
-static long mmtimer_ioctl(struct file *file, unsigned int cmd,
+static int mmtimer_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg);
 static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma);
 
@@ -365,7 +365,7 @@ restart:
  * %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it
  * in the address specified by @arg.
  */
-static long mmtimer_ioctl(struct file *file, unsigned int cmd,
+static int mmtimer_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	int ret = 0;
diff --git a/drivers/char/mwave/mwavedd.c b/drivers/char/mwave/mwavedd.c
index 4f8d67f..41a3af0 100644
--- a/drivers/char/mwave/mwavedd.c
+++ b/drivers/char/mwave/mwavedd.c
@@ -86,7 +86,7 @@ module_param(mwave_uart_io, int, 0);
 
 static int mwave_open(struct inode *inode, struct file *file);
 static int mwave_close(struct inode *inode, struct file *file);
-static long mwave_ioctl(struct file *filp, unsigned int iocmd,
+static int mwave_ioctl(struct inode *inode, struct file *filp, unsigned int iocmd,
 							unsigned long ioarg);
 
 MWAVE_DEVICE_DATA mwave_s_mdd;
@@ -119,7 +119,7 @@ static int mwave_close(struct inode *inode, struct file *file)
 	return retval;
 }
 
-static long mwave_ioctl(struct file *file, unsigned int iocmd,
+static int mwave_ioctl(struct inode *inode, struct file *file, unsigned int iocmd,
 							unsigned long ioarg)
 {
 	unsigned int retval = 0;
diff --git a/drivers/char/pcmcia/cm4000_cs.c b/drivers/char/pcmcia/cm4000_cs.c
index f070ae7..f556c56 100644
--- a/drivers/char/pcmcia/cm4000_cs.c
+++ b/drivers/char/pcmcia/cm4000_cs.c
@@ -1406,11 +1406,10 @@ static void stop_monitor(struct cm4000_dev *dev)
 	DEBUGP(3, dev, "<- stop_monitor\n");
 }
 
-static long cmm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int cmm_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	struct cm4000_dev *dev = filp->private_data;
 	unsigned int iobase = dev->p_dev->io.BasePort1;
-	struct inode *inode = filp->f_path.dentry->d_inode;
 	struct pcmcia_device *link;
 	int size;
 	int rc;
diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c
index bee39fd..fafcc15 100644
--- a/drivers/char/ppdev.c
+++ b/drivers/char/ppdev.c
@@ -633,7 +633,7 @@ static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	return 0;
 }
 
-static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int pp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	long ret;
 	lock_kernel();
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 1838aa3..93e26d0 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1061,7 +1061,7 @@ static ssize_t random_write(struct file *file, const char __user *buffer,
 	return (ssize_t)count;
 }
 
-static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+static int random_ioctl(struct inode *inode, struct file *f, unsigned int cmd, unsigned long arg)
 {
 	int size, ent_count;
 	int __user *p = (int __user *)arg;
diff --git a/drivers/char/rio/rio_linux.c b/drivers/char/rio/rio_linux.c
index a8f68a3..1fad0e4 100644
--- a/drivers/char/rio/rio_linux.c
+++ b/drivers/char/rio/rio_linux.c
@@ -179,7 +179,7 @@ static int rio_set_real_termios(void *ptr);
 static void rio_hungup(void *ptr);
 static void rio_close(void *ptr);
 static int rio_chars_in_buffer(void *ptr);
-static long rio_fw_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
+static int rio_fw_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg);
 static int rio_init_drivers(void);
 
 static void my_hd(void *addr, int len);
@@ -560,7 +560,7 @@ static void rio_close(void *ptr)
 
 
 
-static long rio_fw_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int rio_fw_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	int rc = 0;
 	func_enter();
diff --git a/drivers/char/rtc.c b/drivers/char/rtc.c
index f53d4d0..3bb7b51 100644
--- a/drivers/char/rtc.c
+++ b/drivers/char/rtc.c
@@ -142,7 +142,7 @@ static DEFINE_TIMER(rtc_irq_timer, rtc_dropped_irq, 0, 0);
 static ssize_t rtc_read(struct file *file, char __user *buf,
 			size_t count, loff_t *ppos);
 
-static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 static void rtc_get_rtc_time(struct rtc_time *rtc_tm);
 
 #ifdef RTC_IRQ
@@ -717,7 +717,7 @@ static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel)
 			    &wtime, sizeof wtime) ? -EFAULT : 0;
 }
 
-static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	long ret;
 	lock_kernel();
diff --git a/drivers/char/sx.c b/drivers/char/sx.c
index c385206..54d0c48 100644
--- a/drivers/char/sx.c
+++ b/drivers/char/sx.c
@@ -286,7 +286,7 @@ static void sx_close(void *ptr);
 static int sx_chars_in_buffer(void *ptr);
 static int sx_init_board(struct sx_board *board);
 static int sx_init_portstructs(int nboards, int nports);
-static long sx_fw_ioctl(struct file *filp, unsigned int cmd,
+static int sx_fw_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 						unsigned long arg);
 static int sx_init_drivers(void);
 
@@ -1686,7 +1686,7 @@ static int do_memtest_w(struct sx_board *board, int min, int max)
 }
 #endif
 
-static long sx_fw_ioctl(struct file *filp, unsigned int cmd,
+static int sx_fw_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 							unsigned long arg)
 {
 	long rc = 0;
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index daeb8f7..835658b 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -150,9 +150,9 @@ ssize_t redirected_tty_write(struct file *, const char __user *,
 static unsigned int tty_poll(struct file *, poll_table *);
 static int tty_open(struct inode *, struct file *);
 static int tty_release(struct inode *, struct file *);
-long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+int tty_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 #ifdef CONFIG_COMPAT
-static long tty_compat_ioctl(struct file *file, unsigned int cmd,
+static int tty_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 				unsigned long arg);
 #else
 #define tty_compat_ioctl NULL
@@ -785,13 +785,13 @@ static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait)
 	return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM;
 }
 
-static long hung_up_tty_ioctl(struct file *file, unsigned int cmd,
+static int hung_up_tty_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 		unsigned long arg)
 {
 	return cmd == TIOCSPGRP ? -ENOTTY : -EIO;
 }
 
-static long hung_up_tty_compat_ioctl(struct file *file,
+static int hung_up_tty_compat_ioctl(struct inode *inode, struct file *file,
 				     unsigned int cmd, unsigned long arg)
 {
 	return cmd == TIOCSPGRP ? -ENOTTY : -EIO;
@@ -2941,13 +2941,12 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int
 /*
  * Split this up, as gcc can choke on it otherwise..
  */
-long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int tty_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct tty_struct *tty, *real_tty;
 	void __user *p = (void __user *)arg;
 	int retval;
 	struct tty_ldisc *ld;
-	struct inode *inode = file->f_dentry->d_inode;
 
 	tty = (struct tty_struct *)file->private_data;
 	if (tty_paranoia_check(tty, inode, "tty_ioctl"))
@@ -3075,10 +3074,9 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 }
 
 #ifdef CONFIG_COMPAT
-static long tty_compat_ioctl(struct file *file, unsigned int cmd,
+static int tty_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 				unsigned long arg)
 {
-	struct inode *inode = file->f_dentry->d_inode;
 	struct tty_struct *tty = file->private_data;
 	struct tty_ldisc *ld;
 	int retval = -ENOIOCTLCMD;
diff --git a/drivers/char/viotape.c b/drivers/char/viotape.c
index 7a70a40..649b50e 100644
--- a/drivers/char/viotape.c
+++ b/drivers/char/viotape.c
@@ -678,7 +678,7 @@ free_op:
 	return ret;
 }
 
-static long viotap_unlocked_ioctl(struct file *file,
+static int viotap_unlocked_ioctl(struct inode *inode, struct file *file,
 		unsigned int cmd, unsigned long arg)
 {
 	long rc;
diff --git a/drivers/firewire/fw-cdev.c b/drivers/firewire/fw-cdev.c
index 2e6d584..c7b1e3d 100644
--- a/drivers/firewire/fw-cdev.c
+++ b/drivers/firewire/fw-cdev.c
@@ -916,8 +916,8 @@ dispatch_ioctl(struct client *client, unsigned int cmd, void __user *arg)
 	return 0;
 }
 
-static long
-fw_device_op_ioctl(struct file *file,
+static int
+fw_device_op_ioctl(struct inode *inode, struct file *file,
 		   unsigned int cmd, unsigned long arg)
 {
 	struct client *client = file->private_data;
@@ -929,8 +929,8 @@ fw_device_op_ioctl(struct file *file,
 }
 
 #ifdef CONFIG_COMPAT
-static long
-fw_device_op_compat_ioctl(struct file *file,
+static int
+fw_device_op_compat_ioctl(struct inode *inode, struct file *file,
 			  unsigned int cmd, unsigned long arg)
 {
 	struct client *client = file->private_data;
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index d7326d9..ecc9ce6 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -216,7 +216,7 @@ extern void i915_driver_lastclose(struct drm_device * dev);
 extern void i915_driver_preclose(struct drm_device *dev,
 				 struct drm_file *file_priv);
 extern int i915_driver_device_is_agp(struct drm_device * dev);
-extern long i915_compat_ioctl(struct file *filp, unsigned int cmd,
+extern int i915_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 			      unsigned long arg);
 
 /* i915_irq.c */
diff --git a/drivers/gpu/drm/i915/i915_ioc32.c b/drivers/gpu/drm/i915/i915_ioc32.c
index 1fe68a2..f8f623e 100644
--- a/drivers/gpu/drm/i915/i915_ioc32.c
+++ b/drivers/gpu/drm/i915/i915_ioc32.c
@@ -199,7 +199,7 @@ drm_ioctl_compat_t *i915_compat_ioctls[] = {
  * \param arg user argument.
  * \return zero on success or negative number on failure.
  */
-long i915_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int i915_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	unsigned int nr = DRM_IOCTL_NR(cmd);
 	drm_ioctl_compat_t *fn = NULL;
diff --git a/drivers/gpu/drm/mga/mga_drv.h b/drivers/gpu/drm/mga/mga_drv.h
index f6ebd24..dfe6cd7 100644
--- a/drivers/gpu/drm/mga/mga_drv.h
+++ b/drivers/gpu/drm/mga/mga_drv.h
@@ -187,7 +187,7 @@ extern irqreturn_t mga_driver_irq_handler(DRM_IRQ_ARGS);
 extern void mga_driver_irq_preinstall(struct drm_device * dev);
 extern void mga_driver_irq_postinstall(struct drm_device * dev);
 extern void mga_driver_irq_uninstall(struct drm_device * dev);
-extern long mga_compat_ioctl(struct file *filp, unsigned int cmd,
+extern int mga_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 			     unsigned long arg);
 
 #define mga_flush_write_combine()	DRM_WRITEMEMORYBARRIER()
diff --git a/drivers/gpu/drm/mga/mga_ioc32.c b/drivers/gpu/drm/mga/mga_ioc32.c
index 30d0047..b5d0826 100644
--- a/drivers/gpu/drm/mga/mga_ioc32.c
+++ b/drivers/gpu/drm/mga/mga_ioc32.c
@@ -208,7 +208,7 @@ drm_ioctl_compat_t *mga_compat_ioctls[] = {
  * \param arg user argument.
  * \return zero on success or negative number on failure.
  */
-long mga_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int mga_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	unsigned int nr = DRM_IOCTL_NR(cmd);
 	drm_ioctl_compat_t *fn = NULL;
diff --git a/drivers/gpu/drm/r128/r128_drv.h b/drivers/gpu/drm/r128/r128_drv.h
index 011105e..e145952 100644
--- a/drivers/gpu/drm/r128/r128_drv.h
+++ b/drivers/gpu/drm/r128/r128_drv.h
@@ -159,7 +159,7 @@ extern void r128_driver_lastclose(struct drm_device * dev);
 extern void r128_driver_preclose(struct drm_device * dev,
 				 struct drm_file *file_priv);
 
-extern long r128_compat_ioctl(struct file *filp, unsigned int cmd,
+extern int r128_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 			      unsigned long arg);
 
 /* Register definitions, register access macros and drmAddMap constants
diff --git a/drivers/gpu/drm/r128/r128_ioc32.c b/drivers/gpu/drm/r128/r128_ioc32.c
index d3cb676..f242fdb 100644
--- a/drivers/gpu/drm/r128/r128_ioc32.c
+++ b/drivers/gpu/drm/r128/r128_ioc32.c
@@ -198,7 +198,7 @@ drm_ioctl_compat_t *r128_compat_ioctls[] = {
  * \param arg user argument.
  * \return zero on success or negative number on failure.
  */
-long r128_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int r128_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	unsigned int nr = DRM_IOCTL_NR(cmd);
 	drm_ioctl_compat_t *fn = NULL;
diff --git a/drivers/gpu/drm/radeon/radeon_drv.h b/drivers/gpu/drm/radeon/radeon_drv.h
index 0993816..4b55abd 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.h
+++ b/drivers/gpu/drm/radeon/radeon_drv.h
@@ -401,7 +401,7 @@ extern void radeon_driver_preclose(struct drm_device * dev, struct drm_file *fil
 extern void radeon_driver_postclose(struct drm_device * dev, struct drm_file * filp);
 extern void radeon_driver_lastclose(struct drm_device * dev);
 extern int radeon_driver_open(struct drm_device * dev, struct drm_file * filp_priv);
-extern long radeon_compat_ioctl(struct file *filp, unsigned int cmd,
+extern int radeon_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 				unsigned long arg);
 
 /* r300_cmdbuf.c */
diff --git a/drivers/gpu/drm/radeon/radeon_ioc32.c b/drivers/gpu/drm/radeon/radeon_ioc32.c
index 56decda..6b518cb 100644
--- a/drivers/gpu/drm/radeon/radeon_ioc32.c
+++ b/drivers/gpu/drm/radeon/radeon_ioc32.c
@@ -401,7 +401,7 @@ drm_ioctl_compat_t *radeon_compat_ioctls[] = {
  * \param arg user argument.
  * \return zero on success or negative number on failure.
  */
-long radeon_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int radeon_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	unsigned int nr = DRM_IOCTL_NR(cmd);
 	drm_ioctl_compat_t *fn = NULL;
diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
index c40f040..0a15260 100644
--- a/drivers/hid/hidraw.c
+++ b/drivers/hid/hidraw.c
@@ -217,10 +217,9 @@ static int hidraw_release(struct inode * inode, struct file * file)
 	return 0;
 }
 
-static long hidraw_ioctl(struct file *file, unsigned int cmd,
+static int hidraw_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	unsigned int minor = iminor(inode);
 	long ret = 0;
 	/* FIXME: What stops hidraw_table going NULL */
diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index 842e9ed..0b08caf 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c
@@ -544,7 +544,7 @@ static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd,
 	return len;
 }
 
-static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct hiddev_list *list = file->private_data;
 	struct hiddev *hiddev = list->hiddev;
@@ -761,9 +761,9 @@ static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 }
 
 #ifdef CONFIG_COMPAT
-static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int hiddev_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
-	return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+	return hiddev_ioctl(inode, file, cmd, (unsigned long)compat_ptr(arg));
 }
 #endif
 
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index af4491f..98ec3d2 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -367,7 +367,7 @@ static noinline int i2cdev_ioctl_smbus(struct i2c_client *client,
 	return res;
 }
 
-static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int i2cdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct i2c_client *client = (struct i2c_client *)file->private_data;
 	unsigned long funcs;
diff --git a/drivers/ieee1394/dv1394.c b/drivers/ieee1394/dv1394.c
index b6eb2cf..a8bdc2c 100644
--- a/drivers/ieee1394/dv1394.c
+++ b/drivers/ieee1394/dv1394.c
@@ -158,7 +158,7 @@ static void it_tasklet_func(unsigned long data);
 static void ir_tasklet_func(unsigned long data);
 
 #ifdef CONFIG_COMPAT
-static long dv1394_compat_ioctl(struct file *file, unsigned int cmd,
+static int dv1394_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 			       unsigned long arg);
 #endif
 
@@ -1533,7 +1533,7 @@ static ssize_t dv1394_read(struct file *file,  char __user *buffer, size_t count
 
 /*** DEVICE IOCTL INTERFACE ************************************************/
 
-static long dv1394_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int dv1394_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct video_card *video = file_to_video_card(file);
 	unsigned long flags;
@@ -2457,7 +2457,7 @@ struct dv1394_status32 {
 
 /* RED-PEN: this should use compat_alloc_userspace instead */
 
-static int handle_dv1394_init(struct file *file, unsigned int cmd, unsigned long arg)
+static int handle_dv1394_init(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct dv1394_init32 dv32;
 	struct dv1394_init dv;
@@ -2480,13 +2480,13 @@ static int handle_dv1394_init(struct file *file, unsigned int cmd, unsigned long
 
 	old_fs = get_fs();
 	set_fs(KERNEL_DS);
-	ret = dv1394_ioctl(file, DV1394_IOC_INIT, (unsigned long)&dv);
+	ret = dv1394_ioctl(inode, file, DV1394_IOC_INIT, (unsigned long)&dv);
 	set_fs(old_fs);
 
 	return ret;
 }
 
-static int handle_dv1394_get_status(struct file *file, unsigned int cmd, unsigned long arg)
+static int handle_dv1394_get_status(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct dv1394_status32 dv32;
 	struct dv1394_status dv;
@@ -2498,7 +2498,7 @@ static int handle_dv1394_get_status(struct file *file, unsigned int cmd, unsigne
 
 	old_fs = get_fs();
 	set_fs(KERNEL_DS);
-	ret = dv1394_ioctl(file, DV1394_IOC_GET_STATUS, (unsigned long)&dv);
+	ret = dv1394_ioctl(inode, file, DV1394_IOC_GET_STATUS, (unsigned long)&dv);
 	set_fs(old_fs);
 
 	if (!ret) {
@@ -2523,7 +2523,7 @@ static int handle_dv1394_get_status(struct file *file, unsigned int cmd, unsigne
 
 
 
-static long dv1394_compat_ioctl(struct file *file, unsigned int cmd,
+static int dv1394_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 			       unsigned long arg)
 {
 	switch (cmd) {
@@ -2532,12 +2532,12 @@ static long dv1394_compat_ioctl(struct file *file, unsigned int cmd,
 	case DV1394_IOC_WAIT_FRAMES:
 	case DV1394_IOC_RECEIVE_FRAMES:
 	case DV1394_IOC_START_RECEIVE:
-		return dv1394_ioctl(file, cmd, arg);
+		return dv1394_ioctl(inode, file, cmd, arg);
 
 	case DV1394_IOC32_INIT:
-		return handle_dv1394_init(file, cmd, arg);
+		return handle_dv1394_init(inode, file, cmd, arg);
 	case DV1394_IOC32_GET_STATUS:
-		return handle_dv1394_get_status(file, cmd, arg);
+		return handle_dv1394_get_status(inode, file, cmd, arg);
 	default:
 		return -ENOIOCTLCMD;
 	}
diff --git a/drivers/ieee1394/raw1394.c b/drivers/ieee1394/raw1394.c
index 6fa9e4a..6cf46fa 100644
--- a/drivers/ieee1394/raw1394.c
+++ b/drivers/ieee1394/raw1394.c
@@ -2656,7 +2656,7 @@ static long do_raw1394_ioctl(struct file *file, unsigned int cmd,
 	return -EINVAL;
 }
 
-static long raw1394_ioctl(struct file *file, unsigned int cmd,
+static int raw1394_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	long ret;
@@ -2717,7 +2717,7 @@ static long raw1394_read_cycle_timer32(struct file_info *fi, void __user * uaddr
 	return err;
 }
 
-static long raw1394_compat_ioctl(struct file *file,
+static int raw1394_compat_ioctl(struct inode *inode, struct file *file,
 				 unsigned int cmd, unsigned long arg)
 {
 	struct file_info *fi = file->private_data;
diff --git a/drivers/ieee1394/video1394.c b/drivers/ieee1394/video1394.c
index 25db6e6..ed4eb78 100644
--- a/drivers/ieee1394/video1394.c
+++ b/drivers/ieee1394/video1394.c
@@ -716,7 +716,7 @@ static inline unsigned video1394_buffer_state(struct dma_iso_ctx *d,
 	return ret;
 }
 
-static long video1394_ioctl(struct file *file,
+static int video1394_ioctl(struct inode *inode, struct file *file,
 			    unsigned int cmd, unsigned long arg)
 {
 	struct file_ctx *ctx = (struct file_ctx *)file->private_data;
@@ -1272,7 +1272,7 @@ static int video1394_release(struct inode *inode, struct file *file)
 }
 
 #ifdef CONFIG_COMPAT
-static long video1394_compat_ioctl(struct file *f, unsigned cmd, unsigned long arg);
+static int video1394_compat_ioctl(struct inode *inode, struct file *f, unsigned cmd, unsigned long arg);
 #endif
 
 static struct cdev video1394_cdev;
@@ -1386,7 +1386,7 @@ struct video1394_wait32 {
 	struct compat_timeval filltime;
 };
 
-static int video1394_wr_wait32(struct file *file, unsigned int cmd, unsigned long arg)
+static int video1394_wr_wait32(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
         struct video1394_wait32 __user *argp = (void __user *)arg;
         struct video1394_wait32 wait32;
@@ -1405,11 +1405,11 @@ static int video1394_wr_wait32(struct file *file, unsigned int cmd, unsigned lon
         old_fs = get_fs();
         set_fs(KERNEL_DS);
         if (cmd == VIDEO1394_IOC32_LISTEN_WAIT_BUFFER)
-		ret = video1394_ioctl(file,
+		ret = video1394_ioctl(inode, file,
 				      VIDEO1394_IOC_LISTEN_WAIT_BUFFER,
 				      (unsigned long) &wait);
         else
-		ret = video1394_ioctl(file,
+		ret = video1394_ioctl(inode, file,
 				      VIDEO1394_IOC_LISTEN_POLL_BUFFER,
 				      (unsigned long) &wait);
         set_fs(old_fs);
@@ -1427,7 +1427,7 @@ static int video1394_wr_wait32(struct file *file, unsigned int cmd, unsigned lon
         return ret;
 }
 
-static int video1394_w_wait32(struct file *file, unsigned int cmd, unsigned long arg)
+static int video1394_w_wait32(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
         struct video1394_wait32 wait32;
         struct video1394_wait wait;
@@ -1445,11 +1445,11 @@ static int video1394_w_wait32(struct file *file, unsigned int cmd, unsigned long
         old_fs = get_fs();
         set_fs(KERNEL_DS);
         if (cmd == VIDEO1394_IOC32_LISTEN_QUEUE_BUFFER)
-		ret = video1394_ioctl(file,
+		ret = video1394_ioctl(inode, file,
 				      VIDEO1394_IOC_LISTEN_QUEUE_BUFFER,
 				      (unsigned long) &wait);
         else
-		ret = video1394_ioctl(file,
+		ret = video1394_ioctl(inode, file,
 				      VIDEO1394_IOC_TALK_WAIT_BUFFER,
 				      (unsigned long) &wait);
         set_fs(old_fs);
@@ -1457,33 +1457,33 @@ static int video1394_w_wait32(struct file *file, unsigned int cmd, unsigned long
         return ret;
 }
 
-static int video1394_queue_buf32(struct file *file, unsigned int cmd, unsigned long arg)
+static int video1394_queue_buf32(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
         return -EFAULT;   /* ??? was there before. */
 
-	return video1394_ioctl(file,
+	return video1394_ioctl(inode, file,
 				VIDEO1394_IOC_TALK_QUEUE_BUFFER, arg);
 }
 
-static long video1394_compat_ioctl(struct file *f, unsigned cmd, unsigned long arg)
+static int video1394_compat_ioctl(struct inode *inode, struct file *f, unsigned cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case VIDEO1394_IOC_LISTEN_CHANNEL:
 	case VIDEO1394_IOC_UNLISTEN_CHANNEL:
 	case VIDEO1394_IOC_TALK_CHANNEL:
 	case VIDEO1394_IOC_UNTALK_CHANNEL:
-		return video1394_ioctl(f, cmd, arg);
+		return video1394_ioctl(inode, f, cmd, arg);
 
 	case VIDEO1394_IOC32_LISTEN_QUEUE_BUFFER:
-		return video1394_w_wait32(f, cmd, arg);
+		return video1394_w_wait32(inode, f, cmd, arg);
 	case VIDEO1394_IOC32_LISTEN_WAIT_BUFFER:
-		return video1394_wr_wait32(f, cmd, arg);
+		return video1394_wr_wait32(inode, f, cmd, arg);
 	case VIDEO1394_IOC_TALK_QUEUE_BUFFER:
-		return video1394_queue_buf32(f, cmd, arg);
+		return video1394_queue_buf32(inode, f, cmd, arg);
 	case VIDEO1394_IOC32_TALK_WAIT_BUFFER:
-		return video1394_w_wait32(f, cmd, arg);
+		return video1394_w_wait32(inode, f, cmd, arg);
 	case VIDEO1394_IOC32_LISTEN_POLL_BUFFER:
-		return video1394_wr_wait32(f, cmd, arg);
+		return video1394_wr_wait32(inode, f, cmd, arg);
 	default:
 		return -ENOIOCTLCMD;
 	}
diff --git a/drivers/infiniband/core/user_mad.c b/drivers/infiniband/core/user_mad.c
index 268a2d2..6cd0bc3 100644
--- a/drivers/infiniband/core/user_mad.c
+++ b/drivers/infiniband/core/user_mad.c
@@ -743,7 +743,7 @@ static long ib_umad_enable_pkey(struct ib_umad_file *file)
 	return ret;
 }
 
-static long ib_umad_ioctl(struct file *filp, unsigned int cmd,
+static int ib_umad_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 			  unsigned long arg)
 {
 	switch (cmd) {
@@ -759,7 +759,7 @@ static long ib_umad_ioctl(struct file *filp, unsigned int cmd,
 }
 
 #ifdef CONFIG_COMPAT
-static long ib_umad_compat_ioctl(struct file *filp, unsigned int cmd,
+static int ib_umad_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 				 unsigned long arg)
 {
 	switch (cmd) {
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index 3524bef..9fd8fa9 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -888,13 +888,13 @@ static long evdev_ioctl_handler(struct file *file, unsigned int cmd,
 	return retval;
 }
 
-static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int evdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0);
 }
 
 #ifdef CONFIG_COMPAT
-static long evdev_ioctl_compat(struct file *file,
+static int evdev_ioctl_compat(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
 	return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1);
diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c
index 65d7077..d4db145 100644
--- a/drivers/input/joydev.c
+++ b/drivers/input/joydev.c
@@ -555,7 +555,7 @@ static int joydev_ioctl_common(struct joydev *joydev,
 }
 
 #ifdef CONFIG_COMPAT
-static long joydev_compat_ioctl(struct file *file,
+static int joydev_compat_ioctl(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
 	struct joydev_client *client = file->private_data;
@@ -622,7 +622,7 @@ static long joydev_compat_ioctl(struct file *file,
 }
 #endif /* CONFIG_COMPAT */
 
-static long joydev_ioctl(struct file *file,
+static int joydev_ioctl(struct inode *inode, struct file *file,
 			 unsigned int cmd, unsigned long arg)
 {
 	struct joydev_client *client = file->private_data;
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index 223d56d..a37877e 100644
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -455,7 +455,7 @@ static int uinput_release(struct inode *inode, struct file *file)
 	__ret;						\
 })
 
-static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int uinput_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int			retval;
 	struct uinput_device	*udev;
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index b262c00..c21cbdc 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1470,15 +1470,15 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
 	return r;
 }
 
-static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
+static int dm_ctl_ioctl(struct inode *inode, struct file *file, uint command, ulong u)
 {
 	return (long)ctl_ioctl(command, (struct dm_ioctl __user *)u);
 }
 
 #ifdef CONFIG_COMPAT
-static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
+static int dm_compat_ctl_ioctl(struct inode *inode, struct file *file, uint command, ulong u)
 {
-	return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
+	return dm_ctl_ioctl(inode, file, command, (ulong) compat_ptr(u));
 }
 #else
 #define dm_compat_ctl_ioctl NULL
diff --git a/drivers/media/video/compat_ioctl32.c b/drivers/media/video/compat_ioctl32.c
index bd5d9de..7eacc2d 100644
--- a/drivers/media/video/compat_ioctl32.c
+++ b/drivers/media/video/compat_ioctl32.c
@@ -110,15 +110,15 @@ struct video_window32 {
 };
 #endif
 
-static int native_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int native_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int ret = -ENOIOCTLCMD;
 
 	if (file->f_op->unlocked_ioctl)
-		ret = file->f_op->unlocked_ioctl(file, cmd, arg);
+		ret = file->f_op->unlocked_ioctl(inode, file, cmd, arg);
 	else if (file->f_op->ioctl) {
 		lock_kernel();
-		ret = file->f_op->ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
+		ret = file->f_op->ioctl(inode, file, cmd, arg);
 		unlock_kernel();
 	}
 
@@ -549,7 +549,7 @@ enum {
 	MaxClips = (~0U-sizeof(struct video_window))/sizeof(struct video_clip)
 };
 
-static int do_set_window(struct file *file, unsigned int cmd, unsigned long arg)
+static int do_set_window(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct video_window32 __user *up = compat_ptr(arg);
 	struct video_window __user *vw;
@@ -607,11 +607,11 @@ static int do_set_window(struct file *file, unsigned int cmd, unsigned long arg)
 		}
 	}
 
-	return native_ioctl(file, VIDIOCSWIN, (unsigned long)vw);
+	return native_ioctl(inode, file, VIDIOCSWIN, (unsigned long)vw);
 }
 #endif
 
-static int do_video_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int do_video_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	union {
 #ifdef CONFIG_VIDEO_V4L1_COMPAT
@@ -754,12 +754,12 @@ static int do_video_ioctl(struct file *file, unsigned int cmd, unsigned long arg
 		goto out;
 
 	if(compatible_arg)
-		err = native_ioctl(file, realcmd, (unsigned long)up);
+		err = native_ioctl(inode, file, realcmd, (unsigned long)up);
 	else {
 		mm_segment_t old_fs = get_fs();
 
 		set_fs(KERNEL_DS);
-		err = native_ioctl(file, realcmd, (unsigned long) &karg);
+		err = native_ioctl(inode, file, realcmd, (unsigned long) &karg);
 		set_fs(old_fs);
 	}
 	if(err == 0) {
@@ -827,7 +827,7 @@ out:
 	return err;
 }
 
-long v4l_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg)
+int v4l_compat_ioctl32(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int ret = -ENOIOCTLCMD;
 
@@ -837,7 +837,7 @@ long v4l_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg)
 	switch (cmd) {
 #ifdef CONFIG_VIDEO_V4L1_COMPAT
 	case VIDIOCSWIN32:
-		ret = do_set_window(file, cmd, arg);
+		ret = do_set_window(inode, file, cmd, arg);
 		break;
 	case VIDIOCGTUNER32:
 	case VIDIOCSTUNER32:
@@ -885,7 +885,7 @@ long v4l_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg)
 	case VIDIOC_S_INPUT32:
 	case VIDIOC_TRY_FMT32:
 	case VIDIOC_S_HW_FREQ_SEEK:
-		ret = do_video_ioctl(file, cmd, arg);
+		ret = do_video_ioctl(inode, file, cmd, arg);
 		break;
 
 #ifdef CONFIG_VIDEO_V4L1_COMPAT
@@ -913,7 +913,7 @@ long v4l_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg)
 	case _IOR('v' , BASE_VIDIOCPRIVATE+5, int):
 	case _IOR('v' , BASE_VIDIOCPRIVATE+6, int):
 	case _IOR('v' , BASE_VIDIOCPRIVATE+7, int):
-		ret = native_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+		ret = native_ioctl(inode, file, cmd, (unsigned long)compat_ptr(arg));
 		break;
 #endif
 	default:
@@ -922,7 +922,7 @@ long v4l_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg)
 	return ret;
 }
 #else
-long v4l_compat_ioctl32(struct file *file, unsigned int cmd, unsigned long arg)
+int v4l_compat_ioctl32(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	return -ENOIOCTLCMD;
 }
diff --git a/drivers/message/fusion/mptctl.c b/drivers/message/fusion/mptctl.c
index f5233f3..3d20a3c 100644
--- a/drivers/message/fusion/mptctl.c
+++ b/drivers/message/fusion/mptctl.c
@@ -116,7 +116,7 @@ static int  mptctl_probe(struct pci_dev *, const struct pci_device_id *);
 static void mptctl_remove(struct pci_dev *);
 
 #ifdef CONFIG_COMPAT
-static long compat_mpctl_ioctl(struct file *f, unsigned cmd, unsigned long arg);
+static int compat_mpctl_ioctl(struct inode *inode, struct file *f, unsigned cmd, unsigned long arg);
 #endif
 /*
  * Private function calls.
@@ -652,8 +652,8 @@ __mptctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	return ret;
 }
 
-static long
-mptctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int
+mptctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	long ret;
 	lock_kernel();
@@ -2818,7 +2818,7 @@ compat_mpt_command(struct file *filp, unsigned int cmd,
 	return ret;
 }
 
-static long compat_mpctl_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+static int compat_mpctl_ioctl(struct inode *inode, struct file *f, unsigned int cmd, unsigned long arg)
 {
 	long ret;
 	lock_kernel();
diff --git a/drivers/message/i2o/i2o_config.c b/drivers/message/i2o/i2o_config.c
index 4238de9..442cdb3 100644
--- a/drivers/message/i2o/i2o_config.c
+++ b/drivers/message/i2o/i2o_config.c
@@ -746,7 +746,7 @@ out:
 	return rcode;
 }
 
-static long i2o_cfg_compat_ioctl(struct file *file, unsigned cmd,
+static int i2o_cfg_compat_ioctl(struct inode *inode, struct file *file, unsigned cmd,
 				 unsigned long arg)
 {
 	int ret;
diff --git a/drivers/misc/phantom.c b/drivers/misc/phantom.c
index daf5856..4902f28 100644
--- a/drivers/misc/phantom.c
+++ b/drivers/misc/phantom.c
@@ -83,7 +83,7 @@ static int phantom_status(struct phantom_device *dev, unsigned long newstat)
  * File ops
  */
 
-static long phantom_ioctl(struct file *file, unsigned int cmd,
+static int phantom_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 		unsigned long arg)
 {
 	struct phantom_device *dev = file->private_data;
@@ -195,14 +195,14 @@ static long phantom_ioctl(struct file *file, unsigned int cmd,
 }
 
 #ifdef CONFIG_COMPAT
-static long phantom_compat_ioctl(struct file *filp, unsigned int cmd,
+static int phantom_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 		unsigned long arg)
 {
 	if (_IOC_NR(cmd) <= 3 && _IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
 		cmd &= ~(_IOC_SIZEMASK << _IOC_SIZESHIFT);
 		cmd |= sizeof(void *) << _IOC_SIZESHIFT;
 	}
-	return phantom_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
+	return phantom_ioctl(inode, filp, cmd, (unsigned long)compat_ptr(arg));
 }
 #else
 #define phantom_compat_ioctl NULL
diff --git a/drivers/misc/sgi-gru/grufile.c b/drivers/misc/sgi-gru/grufile.c
index 23c91f5..fb6d7ad 100644
--- a/drivers/misc/sgi-gru/grufile.c
+++ b/drivers/misc/sgi-gru/grufile.c
@@ -233,7 +233,7 @@ static long gru_get_chiplet_status(unsigned long arg)
  *
  * Called to update file attributes via IOCTL calls.
  */
-static long gru_file_unlocked_ioctl(struct file *file, unsigned int req,
+static int gru_file_unlocked_ioctl(struct inode *inode, struct file *file, unsigned int req,
 				    unsigned long arg)
 {
 	int err = -EBADRQC;
diff --git a/drivers/net/ppp_generic.c b/drivers/net/ppp_generic.c
index ddccc07..3ec394d 100644
--- a/drivers/net/ppp_generic.c
+++ b/drivers/net/ppp_generic.c
@@ -547,7 +547,7 @@ static int get_filter(void __user *arg, struct sock_filter **p)
 }
 #endif /* CONFIG_PPP_FILTER */
 
-static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int ppp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct ppp_file *pf = file->private_data;
 	struct ppp *ppp;
diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
index e1098c3..db5903f 100644
--- a/drivers/pci/proc.c
+++ b/drivers/pci/proc.c
@@ -201,7 +201,7 @@ struct pci_filp_private {
 	int write_combine;
 };
 
-static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
+static int proc_bus_pci_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 			       unsigned long arg)
 {
 	const struct proc_dir_entry *dp = PDE(file->f_dentry->d_inode);
diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c
index f118252..ac41969 100644
--- a/drivers/rtc/rtc-dev.c
+++ b/drivers/rtc/rtc-dev.c
@@ -203,7 +203,7 @@ static unsigned int rtc_dev_poll(struct file *file, poll_table *wait)
 	return (data != 0) ? (POLLIN | POLLRDNORM) : 0;
 }
 
-static long rtc_dev_ioctl(struct file *file,
+static int rtc_dev_ioctl(struct inode *inode, struct file *file,
 		unsigned int cmd, unsigned long arg)
 {
 	int err = 0;
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 31ecaa4..ab20e29 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -611,7 +611,7 @@ void dasd_destroy_partitions(struct dasd_block *);
 
 /* externals in dasd_ioctl.c */
 int  dasd_ioctl(struct inode *, struct file *, unsigned int, unsigned long);
-long dasd_compat_ioctl(struct file *, unsigned int, unsigned long);
+int dasd_compat_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 
 /* externals in dasd_proc.c */
 int dasd_proc_init(void);
diff --git a/drivers/s390/char/tape_char.c b/drivers/s390/char/tape_char.c
index be0ce22..5b42a1f 100644
--- a/drivers/s390/char/tape_char.c
+++ b/drivers/s390/char/tape_char.c
@@ -37,7 +37,7 @@ static int tapechar_open(struct inode *,struct file *);
 static int tapechar_release(struct inode *,struct file *);
 static int tapechar_ioctl(struct inode *, struct file *, unsigned int,
 			  unsigned long);
-static long tapechar_compat_ioctl(struct file *, unsigned int,
+static int tapechar_compat_ioctl(struct inode *inode, struct file *, unsigned int,
 			  unsigned long);
 
 static const struct file_operations tape_fops =
diff --git a/drivers/s390/char/vmcp.c b/drivers/s390/char/vmcp.c
index 09e7d9b..3de2abe 100644
--- a/drivers/s390/char/vmcp.c
+++ b/drivers/s390/char/vmcp.c
@@ -138,7 +138,7 @@ vmcp_write(struct file *file, const char __user *buff, size_t count,
  * let userspace to change the response size, if userspace expects a bigger
  * response
  */
-static long vmcp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int vmcp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct vmcp_session *session;
 	int temp;
diff --git a/drivers/s390/cio/chsc_sch.c b/drivers/s390/cio/chsc_sch.c
index 91ca87a..6a0904e 100644
--- a/drivers/s390/cio/chsc_sch.c
+++ b/drivers/s390/cio/chsc_sch.c
@@ -737,7 +737,7 @@ out_free:
 	return ret;
 }
 
-static long chsc_ioctl(struct file *filp, unsigned int cmd,
+static int chsc_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 		       unsigned long arg)
 {
 	CHSC_MSG(2, "chsc_ioctl called, cmd=%x\n", cmd);
diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c
index cb22b97..6e82f85 100644
--- a/drivers/s390/crypto/zcrypt_api.c
+++ b/drivers/s390/crypto/zcrypt_api.c
@@ -621,7 +621,7 @@ static long zcrypt_ica_status(struct file *filp, unsigned long arg)
 	return ret;
 }
 
-static long zcrypt_unlocked_ioctl(struct file *filp, unsigned int cmd,
+static int zcrypt_unlocked_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 				  unsigned long arg)
 {
 	int rc;
@@ -872,7 +872,7 @@ static long trans_xcRB32(struct file *filp, unsigned int cmd,
 	return rc;
 }
 
-static long zcrypt_compat_ioctl(struct file *filp, unsigned int cmd,
+static int zcrypt_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 			 unsigned long arg)
 {
 	if (cmd == ICARSAMODEXPO)
diff --git a/drivers/s390/scsi/zfcp_cfdc.c b/drivers/s390/scsi/zfcp_cfdc.c
index ec2abce..de0380f 100644
--- a/drivers/s390/scsi/zfcp_cfdc.c
+++ b/drivers/s390/scsi/zfcp_cfdc.c
@@ -160,7 +160,7 @@ static void zfcp_cfdc_req_to_sense(struct zfcp_cfdc_data *data,
 	       sizeof(req->qtcb->bottom.support.els));
 }
 
-static long zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
+static int zfcp_cfdc_dev_ioctl(struct inode *inode, struct file *file, unsigned int command,
 				unsigned long buffer)
 {
 	struct zfcp_cfdc_data *data;
diff --git a/drivers/sbus/char/cpwatchdog.c b/drivers/sbus/char/cpwatchdog.c
index 23abfdf..1d272b6 100644
--- a/drivers/sbus/char/cpwatchdog.c
+++ b/drivers/sbus/char/cpwatchdog.c
@@ -397,7 +397,7 @@ static int wd_ioctl(struct inode *inode, struct file *file,
 	return(0);
 }
 
-static long wd_compat_ioctl(struct file *file, unsigned int cmd,
+static int wd_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 		unsigned long arg)
 {
 	int rval = -ENOIOCTLCMD;
diff --git a/drivers/sbus/char/display7seg.c b/drivers/sbus/char/display7seg.c
index d8f5c0c..74842f3 100644
--- a/drivers/sbus/char/display7seg.c
+++ b/drivers/sbus/char/display7seg.c
@@ -117,7 +117,7 @@ static int d7s_release(struct inode *inode, struct file *f)
 	return 0;
 }
 
-static long d7s_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int d7s_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	__u8 regs = readb(d7s_regs);
 	__u8 ireg = 0;
diff --git a/drivers/sbus/char/openprom.c b/drivers/sbus/char/openprom.c
index 29dc735..9a37df0 100644
--- a/drivers/sbus/char/openprom.c
+++ b/drivers/sbus/char/openprom.c
@@ -650,7 +650,7 @@ static int openprom_ioctl(struct inode * inode, struct file * file,
 	};
 }
 
-static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
+static int openprom_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 		unsigned long arg)
 {
 	long rval = -ENOTTY;
diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
index 9aa301c..ff0ec51 100644
--- a/drivers/scsi/aacraid/linit.c
+++ b/drivers/scsi/aacraid/linit.c
@@ -751,7 +751,7 @@ static int aac_compat_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
 	return aac_compat_do_ioctl(dev, cmd, (unsigned long)arg);
 }
 
-static long aac_compat_cfg_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+static int aac_compat_cfg_ioctl(struct inode *inode, struct file *file, unsigned cmd, unsigned long arg)
 {
 	if (!capable(CAP_SYS_RAWIO))
 		return -EPERM;
diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index 3c257fe..a9ac914 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -596,7 +596,7 @@ ch_checkrange(scsi_changer *ch, unsigned int type, unsigned int unit)
 	return 0;
 }
 
-static long ch_ioctl(struct file *file,
+static int ch_ioctl(struct inode *inode, struct file *file,
 		    unsigned int cmd, unsigned long arg)
 {
 	scsi_changer *ch = file->private_data;
@@ -843,7 +843,7 @@ struct changer_element_status32 {
 };
 #define CHIOGSTATUS32  _IOW('c', 8,struct changer_element_status32)
 
-static long ch_ioctl_compat(struct file * file,
+static int ch_ioctl_compat(struct inode *inode, struct file * file,
 			    unsigned int cmd, unsigned long arg)
 {
 	scsi_changer *ch = file->private_data;
@@ -858,7 +858,7 @@ static long ch_ioctl_compat(struct file * file,
 	case CHIOINITELEM:
 	case CHIOSVOLTAG:
 		/* compatible */
-		return ch_ioctl(file, cmd, arg);
+		return ch_ioctl(inode, file, cmd, arg);
 	case CHIOGSTATUS32:
 	{
 		struct changer_element_status32 ces32;
diff --git a/drivers/scsi/dpt_i2o.c b/drivers/scsi/dpt_i2o.c
index 1fe0901..0c4e821 100644
--- a/drivers/scsi/dpt_i2o.c
+++ b/drivers/scsi/dpt_i2o.c
@@ -115,7 +115,7 @@ static int hba_count = 0;
 static struct class *adpt_sysfs_class;
 
 #ifdef CONFIG_COMPAT
-static long compat_adpt_ioctl(struct file *, unsigned int, unsigned long);
+static int compat_adpt_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 #endif
 
 static const struct file_operations adpt_fops = {
@@ -2147,14 +2147,11 @@ static int adpt_ioctl(struct inode *inode, struct file *file, uint cmd,
 }
 
 #ifdef CONFIG_COMPAT
-static long compat_adpt_ioctl(struct file *file,
+static int compat_adpt_ioctl(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode;
 	long ret;
  
-	inode = file->f_dentry->d_inode;
- 
 	lock_kernel();
  
 	switch(cmd) {
diff --git a/drivers/scsi/megaraid/megaraid_mm.c b/drivers/scsi/megaraid/megaraid_mm.c
index f680561..e3d9a55 100644
--- a/drivers/scsi/megaraid/megaraid_mm.c
+++ b/drivers/scsi/megaraid/megaraid_mm.c
@@ -44,7 +44,7 @@ static void mraid_mm_free_adp_resources(mraid_mmadp_t *);
 static void mraid_mm_teardown_dma_pools(mraid_mmadp_t *);
 
 #ifdef CONFIG_COMPAT
-static long mraid_mm_compat_ioctl(struct file *, unsigned int, unsigned long);
+static int mraid_mm_compat_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 #endif
 
 MODULE_AUTHOR("LSI Logic Corporation");
@@ -1218,13 +1218,13 @@ mraid_mm_init(void)
  * @cmd		: ioctl command
  * @arg		: user ioctl packet
  */
-static long
-mraid_mm_compat_ioctl(struct file *filep, unsigned int cmd,
-		      unsigned long arg)
+static int
+mraid_mm_compat_ioctl(struct inode *inode, struct file *filep,
+		      unsigned int cmd, unsigned long arg)
 {
 	int err;
 
-	err = mraid_mm_ioctl(NULL, filep, cmd, arg);
+	err = mraid_mm_ioctl(inode, filep, cmd, arg);
 
 	return err;
 }
diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index 97b7633..8bcd1bd 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -3269,8 +3269,8 @@ static int megasas_mgmt_ioctl_aen(struct file *file, unsigned long arg)
 /**
  * megasas_mgmt_ioctl -	char node ioctl entry point
  */
-static long
-megasas_mgmt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int
+megasas_mgmt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case MEGASAS_IOC_FIRMWARE:
@@ -3324,9 +3324,9 @@ static int megasas_mgmt_compat_ioctl_fw(struct file *file, unsigned long arg)
 	return error;
 }
 
-static long
-megasas_mgmt_compat_ioctl(struct file *file, unsigned int cmd,
-			  unsigned long arg)
+static int
+megasas_mgmt_compat_ioctl(struct inode *inode, struct file *file,
+			  unsigned int cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case MEGASAS_IOC_FIRMWARE32:
diff --git a/drivers/scsi/osst.c b/drivers/scsi/osst.c
index 1c79f97..4d6867f 100644
--- a/drivers/scsi/osst.c
+++ b/drivers/scsi/osst.c
@@ -5191,7 +5191,7 @@ out:
 }
 
 #ifdef CONFIG_COMPAT
-static long osst_compat_ioctl(struct file * file, unsigned int cmd_in, unsigned long arg)
+static int osst_compat_ioctl(struct inode *inode, struct file * file, unsigned int cmd_in, unsigned long arg)
 {
 	struct osst_tape *STp = file->private_data;
 	struct scsi_device *sdev = STp->device;
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index e5e7d78..e283650 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -921,7 +921,7 @@ static void sd_rescan(struct device *dev)
  * This gets directly called from VFS. When the ioctl 
  * is not recognized we go back to the other translation paths. 
  */
-static long sd_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int sd_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct block_device *bdev = file->f_path.dentry->d_inode->i_bdev;
 	struct gendisk *disk = bdev->bd_disk;
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 661f9f2..5d4e1aa 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1113,7 +1113,7 @@ sg_ioctl(struct inode *inode, struct file *filp,
 }
 
 #ifdef CONFIG_COMPAT
-static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
+static int sg_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd_in, unsigned long arg)
 {
 	Sg_device *sdp;
 	Sg_fd *sfp;
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index c2bb53e..245c8ba 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -3233,7 +3233,7 @@ static int partition_tape(struct scsi_tape *STp, int size)
 
 
 /* The ioctl command */
-static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
+static int st_ioctl(struct inode *inode, struct file *file, unsigned int cmd_in, unsigned long arg)
 {
 	int i, cmd_nr, cmd_type, bt;
 	int retval = 0;
@@ -3586,7 +3586,7 @@ static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
 }
 
 #ifdef CONFIG_COMPAT
-static long st_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int st_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct scsi_tape *STp = file->private_data;
 	struct scsi_device *sdev = STp->device;
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index e5e0cfe..70b3a16 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -299,8 +299,8 @@ done:
 	return status;
 }
 
-static long
-spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int
+spidev_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	int			err = 0;
 	int			retval = 0;
diff --git a/drivers/telephony/ixj.c b/drivers/telephony/ixj.c
index ec7aeb5..afea51d 100644
--- a/drivers/telephony/ixj.c
+++ b/drivers/telephony/ixj.c
@@ -6661,7 +6661,7 @@ static long do_ixj_ioctl(struct file *file_p, unsigned int cmd, unsigned long ar
 	return retval;
 }
 
-static long ixj_ioctl(struct file *file_p, unsigned int cmd, unsigned long arg)
+static int ixj_ioctl(struct inode *inode, struct file *file_p, unsigned int cmd, unsigned long arg)
 {
 	long ret;
 	lock_kernel();
diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c
index 0647164..0fdca42 100644
--- a/drivers/usb/class/usblp.c
+++ b/drivers/usb/class/usblp.c
@@ -487,7 +487,7 @@ static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait
 	return ret;
 }
 
-static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int usblp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct usblp *usblp = file->private_data;
 	int length, err, i;
diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index f4585d3..c772d34 100644
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -482,7 +482,7 @@ ep_release (struct inode *inode, struct file *fd)
 	return 0;
 }
 
-static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
+static int ep_ioctl(struct inode *inode, struct file *fd, unsigned code, unsigned long value)
 {
 	struct ep_data		*data = fd->private_data;
 	int			status;
@@ -1292,7 +1292,7 @@ out:
        return mask;
 }
 
-static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
+static int dev_ioctl(struct inode *inode, struct file *fd, unsigned code, unsigned long value)
 {
 	struct dev_data		*dev = fd->private_data;
 	struct usb_gadget	*gadget = dev->gadget;
@@ -1300,7 +1300,7 @@ static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
 
 	if (gadget->ops->ioctl) {
 		lock_kernel();
-		ret = gadget->ops->ioctl (gadget, code, value);
+		ret = gadget->ops->ioctl(gadget, code, value);
 		unlock_kernel();
 	}
 	return ret;
diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
index e009008..d02ce89 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -828,8 +828,8 @@ printer_poll(struct file *fd, poll_table *wait)
 	return status;
 }
 
-static long
-printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
+static int
+printer_ioctl(struct inode *inode, struct file *fd, unsigned int code, unsigned long arg)
 {
 	struct printer_dev	*dev = fd->private_data;
 	unsigned long		flags;
diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index a4ef77e..5e3411a 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -473,7 +473,7 @@ exit:
 /**
  *	iowarrior_ioctl
  */
-static long iowarrior_ioctl(struct file *file, unsigned int cmd,
+static int iowarrior_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	struct iowarrior *dev = NULL;
diff --git a/drivers/usb/misc/rio500.c b/drivers/usb/misc/rio500.c
index 248a12a..3ba8ef2 100644
--- a/drivers/usb/misc/rio500.c
+++ b/drivers/usb/misc/rio500.c
@@ -104,7 +104,7 @@ static int close_rio(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long ioctl_rio(struct file *file, unsigned int cmd, unsigned long arg)
+static int ioctl_rio(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct RioCommand rio_cmd;
 	struct rio_usb_data *rio = &rio_instance;
diff --git a/drivers/usb/misc/sisusbvga/sisusb.c b/drivers/usb/misc/sisusbvga/sisusb.c
index 69c34a5..26142aa 100644
--- a/drivers/usb/misc/sisusbvga/sisusb.c
+++ b/drivers/usb/misc/sisusbvga/sisusb.c
@@ -2982,8 +2982,8 @@ sisusb_handle_command(struct sisusb_usb_data *sisusb, struct sisusb_command *y,
 	return retval;
 }
 
-static long
-sisusb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int
+sisusb_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct sisusb_usb_data *sisusb;
 	struct sisusb_info x;
@@ -3058,8 +3058,8 @@ err_out:
 }
 
 #ifdef SISUSB_NEW_CONFIG_COMPAT
-static long
-sisusb_compat_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+static int
+sisusb_compat_ioctl(struct inode *inode, struct file *f, unsigned int cmd, unsigned long arg)
 {
 	long retval;
 
@@ -3067,7 +3067,7 @@ sisusb_compat_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 		case SISUSB_GET_CONFIG_SIZE:
 		case SISUSB_GET_CONFIG:
 		case SISUSB_COMMAND:
-			retval = sisusb_ioctl(f, cmd, arg);
+			retval = sisusb_ioctl(inode, f, cmd, arg);
 			return retval;
 
 		default:
diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c
index 2db4228..3f46226 100644
--- a/drivers/usb/misc/usblcd.c
+++ b/drivers/usb/misc/usblcd.c
@@ -146,7 +146,7 @@ static ssize_t lcd_read(struct file *file, char __user * buffer, size_t count, l
 	return retval;
 }
 
-static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int lcd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct usb_lcd *dev;
 	u16 bcdDevice;
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index 98843c2..aebf6f0 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c
@@ -1223,10 +1223,8 @@ static int fb_get_fscreeninfo(struct inode *inode, struct file *file,
 	return err;
 }
 
-static long
-fb_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int fb_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	int fbidx = iminor(inode);
 	struct fb_info *info = registered_fb[fbidx];
 	struct fb_ops *fb = info->fbops;
diff --git a/drivers/watchdog/acquirewdt.c b/drivers/watchdog/acquirewdt.c
index 6e46a55..7579e79 100644
--- a/drivers/watchdog/acquirewdt.c
+++ b/drivers/watchdog/acquirewdt.c
@@ -145,7 +145,7 @@ static ssize_t acq_write(struct file *file, const char __user *buf,
 	return count;
 }
 
-static long acq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int acq_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int options, retval = -EINVAL;
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/advantechwdt.c b/drivers/watchdog/advantechwdt.c
index a5110f9..518c159 100644
--- a/drivers/watchdog/advantechwdt.c
+++ b/drivers/watchdog/advantechwdt.c
@@ -132,7 +132,7 @@ static ssize_t advwdt_write(struct file *file, const char __user *buf,
 	return count;
 }
 
-static long advwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int advwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int new_timeout;
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/alim1535_wdt.c b/drivers/watchdog/alim1535_wdt.c
index 2a7690e..bde5fbc 100644
--- a/drivers/watchdog/alim1535_wdt.c
+++ b/drivers/watchdog/alim1535_wdt.c
@@ -176,7 +176,7 @@ static ssize_t ali_write(struct file *file, const char __user *data,
  *	we want an extension to enable irq ack monitoring and the like
  */
 
-static long ali_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int ali_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/alim7101_wdt.c b/drivers/watchdog/alim7101_wdt.c
index a045ef8..4c0ef21 100644
--- a/drivers/watchdog/alim7101_wdt.c
+++ b/drivers/watchdog/alim7101_wdt.c
@@ -234,7 +234,7 @@ static int fop_close(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/ar7_wdt.c b/drivers/watchdog/ar7_wdt.c
index 55dcbfe..2dcd13e 100644
--- a/drivers/watchdog/ar7_wdt.c
+++ b/drivers/watchdog/ar7_wdt.c
@@ -240,7 +240,7 @@ static ssize_t ar7_wdt_write(struct file *file, const char *data,
 	return len;
 }
 
-static long ar7_wdt_ioctl(struct file *file,
+static int ar7_wdt_ioctl(struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	static struct watchdog_info ident = {
diff --git a/drivers/watchdog/at32ap700x_wdt.c b/drivers/watchdog/at32ap700x_wdt.c
index e8ae638..aafa445 100644
--- a/drivers/watchdog/at32ap700x_wdt.c
+++ b/drivers/watchdog/at32ap700x_wdt.c
@@ -212,7 +212,7 @@ static struct watchdog_info at32_wdt_info = {
 /*
  * Handle commands from user-space.
  */
-static long at32_wdt_ioctl(struct file *file,
+static int at32_wdt_ioctl(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/at91rm9200_wdt.c b/drivers/watchdog/at91rm9200_wdt.c
index 993e5f5..8658fc7 100644
--- a/drivers/watchdog/at91rm9200_wdt.c
+++ b/drivers/watchdog/at91rm9200_wdt.c
@@ -128,7 +128,7 @@ static struct watchdog_info at91_wdt_info = {
 /*
  * Handle commands from user-space.
  */
-static long at91_wdt_ioctl(struct file *file,
+static int at91_wdt_ioctl(struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/bfin_wdt.c b/drivers/watchdog/bfin_wdt.c
index 31b4225..e82f2ed 100644
--- a/drivers/watchdog/bfin_wdt.c
+++ b/drivers/watchdog/bfin_wdt.c
@@ -248,7 +248,7 @@ static ssize_t bfin_wdt_write(struct file *file, const char __user *data,
  *	Query basic information from the device or ping it, as outlined by the
  *	watchdog API.
  */
-static long bfin_wdt_ioctl(struct file *file,
+static int bfin_wdt_ioctl(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/booke_wdt.c b/drivers/watchdog/booke_wdt.c
index c3b78a7..c5a7ce1 100644
--- a/drivers/watchdog/booke_wdt.c
+++ b/drivers/watchdog/booke_wdt.c
@@ -82,7 +82,7 @@ static struct watchdog_info ident = {
 	.identity = "PowerPC Book-E Watchdog",
 };
 
-static long booke_wdt_ioctl(struct file *file,
+static int booke_wdt_ioctl(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
 	u32 tmp = 0;
diff --git a/drivers/watchdog/cpu5wdt.c b/drivers/watchdog/cpu5wdt.c
index 71f6d7e..feb30cd 100644
--- a/drivers/watchdog/cpu5wdt.c
+++ b/drivers/watchdog/cpu5wdt.c
@@ -148,7 +148,7 @@ static int cpu5wdt_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long cpu5wdt_ioctl(struct file *file, unsigned int cmd,
+static int cpu5wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c
index 2e13602..81f676a 100644
--- a/drivers/watchdog/davinci_wdt.c
+++ b/drivers/watchdog/davinci_wdt.c
@@ -142,7 +142,7 @@ static struct watchdog_info ident = {
 	.identity = "DaVinci Watchdog",
 };
 
-static long davinci_wdt_ioctl(struct file *file,
+static int davinci_wdt_ioctl(struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/ep93xx_wdt.c b/drivers/watchdog/ep93xx_wdt.c
index e9f950f..496a5fa 100644
--- a/drivers/watchdog/ep93xx_wdt.c
+++ b/drivers/watchdog/ep93xx_wdt.c
@@ -135,7 +135,7 @@ static struct watchdog_info ident = {
 	.identity = "EP93xx Watchdog",
 };
 
-static long ep93xx_wdt_ioctl(struct file *file,
+static int ep93xx_wdt_ioctl(struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/eurotechwdt.c b/drivers/watchdog/eurotechwdt.c
index bbd14e3..ecb704d 100644
--- a/drivers/watchdog/eurotechwdt.c
+++ b/drivers/watchdog/eurotechwdt.c
@@ -233,7 +233,7 @@ size_t count, loff_t *ppos)
  * according to their available features.
  */
 
-static long eurwdt_ioctl(struct file *file,
+static int eurwdt_ioctl(struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
index a3765e0..de4a065 100644
--- a/drivers/watchdog/hpwdt.c
+++ b/drivers/watchdog/hpwdt.c
@@ -556,7 +556,7 @@ static struct watchdog_info ident = {
 	.identity = "HP iLO2 HW Watchdog Timer",
 };
 
-static long hpwdt_ioctl(struct file *file, unsigned int cmd,
+static int hpwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 	unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/i6300esb.c b/drivers/watchdog/i6300esb.c
index c13383f..013eb0d 100644
--- a/drivers/watchdog/i6300esb.c
+++ b/drivers/watchdog/i6300esb.c
@@ -256,7 +256,7 @@ static ssize_t esb_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long esb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int esb_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int new_options, retval = -EINVAL;
 	int new_heartbeat;
diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index bfb93bc..4d1015a 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -510,7 +510,7 @@ static ssize_t iTCO_wdt_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long iTCO_wdt_ioctl(struct file *file, unsigned int cmd,
+static int iTCO_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int new_options, retval = -EINVAL;
diff --git a/drivers/watchdog/ib700wdt.c b/drivers/watchdog/ib700wdt.c
index 05a2810..53bf64d 100644
--- a/drivers/watchdog/ib700wdt.c
+++ b/drivers/watchdog/ib700wdt.c
@@ -187,7 +187,7 @@ static ssize_t ibwdt_write(struct file *file, const char __user *buf,
 	return count;
 }
 
-static long ibwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int ibwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int new_margin;
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/ibmasr.c b/drivers/watchdog/ibmasr.c
index b82405c..14a32af 100644
--- a/drivers/watchdog/ibmasr.c
+++ b/drivers/watchdog/ibmasr.c
@@ -270,7 +270,7 @@ static ssize_t asr_write(struct file *file, const char __user *buf,
 	return count;
 }
 
-static long asr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int asr_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	static const struct watchdog_info ident = {
 		.options =	WDIOF_KEEPALIVEPING |
diff --git a/drivers/watchdog/indydog.c b/drivers/watchdog/indydog.c
index 73c9e79..97e8619 100644
--- a/drivers/watchdog/indydog.c
+++ b/drivers/watchdog/indydog.c
@@ -108,7 +108,7 @@ static ssize_t indydog_write(struct file *file, const char *data,
 	return len;
 }
 
-static long indydog_ioctl(struct file *file, unsigned int cmd,
+static int indydog_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int options, retval = -EINVAL;
diff --git a/drivers/watchdog/iop_wdt.c b/drivers/watchdog/iop_wdt.c
index 96eb2cb..91070a7 100644
--- a/drivers/watchdog/iop_wdt.c
+++ b/drivers/watchdog/iop_wdt.c
@@ -130,7 +130,7 @@ static const struct watchdog_info ident = {
 	.identity = "iop watchdog",
 };
 
-static long iop_wdt_ioctl(struct file *file,
+static int iop_wdt_ioctl(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
 	int options;
diff --git a/drivers/watchdog/it8712f_wdt.c b/drivers/watchdog/it8712f_wdt.c
index 2270ee0..a2851a6 100644
--- a/drivers/watchdog/it8712f_wdt.c
+++ b/drivers/watchdog/it8712f_wdt.c
@@ -231,7 +231,7 @@ static ssize_t it8712f_wdt_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long it8712f_wdt_ioctl(struct file *file, unsigned int cmd,
+static int it8712f_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/ixp2000_wdt.c b/drivers/watchdog/ixp2000_wdt.c
index 4f4b35a..4e8c501 100644
--- a/drivers/watchdog/ixp2000_wdt.c
+++ b/drivers/watchdog/ixp2000_wdt.c
@@ -105,7 +105,7 @@ static struct watchdog_info ident = {
 	.identity	= "IXP2000 Watchdog",
 };
 
-static long ixp2000_wdt_ioctl(struct file *file, unsigned int cmd,
+static int ixp2000_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/ixp4xx_wdt.c b/drivers/watchdog/ixp4xx_wdt.c
index 8302ef0..0933442 100644
--- a/drivers/watchdog/ixp4xx_wdt.c
+++ b/drivers/watchdog/ixp4xx_wdt.c
@@ -96,7 +96,7 @@ static struct watchdog_info ident = {
 };
 
 
-static long ixp4xx_wdt_ioctl(struct file *file, unsigned int cmd,
+static int ixp4xx_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/ks8695_wdt.c b/drivers/watchdog/ks8695_wdt.c
index 0b798fd..76b310f 100644
--- a/drivers/watchdog/ks8695_wdt.c
+++ b/drivers/watchdog/ks8695_wdt.c
@@ -152,7 +152,7 @@ static struct watchdog_info ks8695_wdt_info = {
 /*
  * Handle commands from user-space.
  */
-static long ks8695_wdt_ioctl(struct file *file, unsigned int cmd,
+static int ks8695_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/machzwd.c b/drivers/watchdog/machzwd.c
index 2dfc275..fb840c5 100644
--- a/drivers/watchdog/machzwd.c
+++ b/drivers/watchdog/machzwd.c
@@ -303,7 +303,7 @@ static ssize_t zf_write(struct file *file, const char __user *buf, size_t count,
 	return count;
 }
 
-static long zf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int zf_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/mixcomwd.c b/drivers/watchdog/mixcomwd.c
index 407b025..cc1d238 100644
--- a/drivers/watchdog/mixcomwd.c
+++ b/drivers/watchdog/mixcomwd.c
@@ -195,7 +195,7 @@ static ssize_t mixcomwd_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long mixcomwd_ioctl(struct file *file,
+static int mixcomwd_ioctl(struct inode *inode, struct file *file,
 				unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/mpc5200_wdt.c b/drivers/watchdog/mpc5200_wdt.c
index db91892..614bc2c 100644
--- a/drivers/watchdog/mpc5200_wdt.c
+++ b/drivers/watchdog/mpc5200_wdt.c
@@ -94,7 +94,7 @@ static struct watchdog_info mpc5200_wdt_info = {
 	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
 	.identity	= "mpc5200 watchdog on GPT0",
 };
-static long mpc5200_wdt_ioctl(struct file *file, unsigned int cmd,
+static int mpc5200_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	struct mpc5200_wdt *wdt = file->private_data;
diff --git a/drivers/watchdog/mpc8xxx_wdt.c b/drivers/watchdog/mpc8xxx_wdt.c
index 38c588e..243bce7 100644
--- a/drivers/watchdog/mpc8xxx_wdt.c
+++ b/drivers/watchdog/mpc8xxx_wdt.c
@@ -143,7 +143,7 @@ static int mpc8xxx_wdt_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long mpc8xxx_wdt_ioctl(struct file *file, unsigned int cmd,
+static int mpc8xxx_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/mpcore_wdt.c b/drivers/watchdog/mpcore_wdt.c
index 2a9bfa8..91db86e 100644
--- a/drivers/watchdog/mpcore_wdt.c
+++ b/drivers/watchdog/mpcore_wdt.c
@@ -218,7 +218,7 @@ static struct watchdog_info ident = {
 	.identity		= "MPcore Watchdog",
 };
 
-static long mpcore_wdt_ioctl(struct file *file, unsigned int cmd,
+static int mpcore_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	struct mpcore_wdt *wdt = file->private_data;
diff --git a/drivers/watchdog/mtx-1_wdt.c b/drivers/watchdog/mtx-1_wdt.c
index b4b7b0a..fd7f85d 100644
--- a/drivers/watchdog/mtx-1_wdt.c
+++ b/drivers/watchdog/mtx-1_wdt.c
@@ -136,7 +136,7 @@ static int mtx1_wdt_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long mtx1_wdt_ioctl(struct file *file, unsigned int cmd,
+static int mtx1_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/mv64x60_wdt.c b/drivers/watchdog/mv64x60_wdt.c
index acf589d..b3dea2d 100644
--- a/drivers/watchdog/mv64x60_wdt.c
+++ b/drivers/watchdog/mv64x60_wdt.c
@@ -173,7 +173,7 @@ static ssize_t mv64x60_wdt_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long mv64x60_wdt_ioctl(struct file *file,
+static int mv64x60_wdt_ioctl(struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	int timeout;
diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
index 3a11dad..8bbc9bf 100644
--- a/drivers/watchdog/omap_wdt.c
+++ b/drivers/watchdog/omap_wdt.c
@@ -185,7 +185,7 @@ static ssize_t omap_wdt_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long omap_wdt_ioctl(struct file *file, unsigned int cmd,
+static int omap_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	int new_margin;
diff --git a/drivers/watchdog/pc87413_wdt.c b/drivers/watchdog/pc87413_wdt.c
index 484c215..9417f9c 100644
--- a/drivers/watchdog/pc87413_wdt.c
+++ b/drivers/watchdog/pc87413_wdt.c
@@ -397,7 +397,7 @@ static ssize_t pc87413_write(struct file *file, const char __user *data,
  *	querying capabilities and current status.
  */
 
-static long pc87413_ioctl(struct file *file, unsigned int cmd,
+static int pc87413_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	int new_timeout;
diff --git a/drivers/watchdog/pcwd.c b/drivers/watchdog/pcwd.c
index 9e1331a..0f6f9a6 100644
--- a/drivers/watchdog/pcwd.c
+++ b/drivers/watchdog/pcwd.c
@@ -594,7 +594,7 @@ static int pcwd_get_temperature(int *temperature)
  *	/dev/watchdog handling
  */
 
-static long pcwd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int pcwd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int rv;
 	int status;
diff --git a/drivers/watchdog/pcwd_pci.c b/drivers/watchdog/pcwd_pci.c
index 90eb1d4..dae0372 100644
--- a/drivers/watchdog/pcwd_pci.c
+++ b/drivers/watchdog/pcwd_pci.c
@@ -453,7 +453,7 @@ static ssize_t pcipcwd_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long pcipcwd_ioctl(struct file *file, unsigned int cmd,
+static int pcipcwd_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/pcwd_usb.c b/drivers/watchdog/pcwd_usb.c
index c1685c9..68419ee 100644
--- a/drivers/watchdog/pcwd_usb.c
+++ b/drivers/watchdog/pcwd_usb.c
@@ -368,7 +368,7 @@ static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
+static int usb_pcwd_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/pnx4008_wdt.c b/drivers/watchdog/pnx4008_wdt.c
index 0ed8416..44ab680 100644
--- a/drivers/watchdog/pnx4008_wdt.c
+++ b/drivers/watchdog/pnx4008_wdt.c
@@ -173,7 +173,7 @@ static const struct watchdog_info ident = {
 	.identity = "PNX4008 Watchdog",
 };
 
-static long pnx4008_wdt_ioctl(struct inode *inode, struct file *file,
+static int pnx4008_wdt_ioctl(struct inode *inode, struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/rm9k_wdt.c b/drivers/watchdog/rm9k_wdt.c
index f1ae372..384738c 100644
--- a/drivers/watchdog/rm9k_wdt.c
+++ b/drivers/watchdog/rm9k_wdt.c
@@ -55,7 +55,7 @@ static int wdt_gpi_open(struct inode *, struct file *);
 static int wdt_gpi_release(struct inode *, struct file *);
 static ssize_t wdt_gpi_write(struct file *, const char __user *, size_t,
 								loff_t *);
-static long wdt_gpi_ioctl(struct file *, unsigned int, unsigned long);
+static int wdt_gpi_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 static int wdt_gpi_notify(struct notifier_block *, unsigned long, void *);
 static const struct resource *wdt_gpi_get_resource(struct platform_device *,
 						const char *, unsigned int);
@@ -244,7 +244,7 @@ static ssize_t wdt_gpi_write(struct file *f, const char __user *d, size_t s,
 	return s ? 1 : 0;
 }
 
-static long wdt_gpi_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+static int wdt_gpi_ioctl(struct inode *inode, struct file *f, unsigned int cmd, unsigned long arg)
 {
 	long res = -ENOTTY;
 	const long size = _IOC_SIZE(cmd);
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 86d4280..28e9488 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -272,7 +272,7 @@ static const struct watchdog_info s3c2410_wdt_ident = {
 };
 
 
-static long s3c2410wdt_ioctl(struct file *file,	unsigned int cmd,
+static int s3c2410wdt_ioctl(struct inode *inode, struct file *file,	unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/sa1100_wdt.c b/drivers/watchdog/sa1100_wdt.c
index 31a4843..30d2bda 100644
--- a/drivers/watchdog/sa1100_wdt.c
+++ b/drivers/watchdog/sa1100_wdt.c
@@ -86,7 +86,7 @@ static const struct watchdog_info ident = {
 	.identity	= "SA1100/PXA255 Watchdog",
 };
 
-static long sa1100dog_ioctl(struct file *file, unsigned int cmd,
+static int sa1100dog_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/sb_wdog.c b/drivers/watchdog/sb_wdog.c
index 27e526a..55aa97b 100644
--- a/drivers/watchdog/sb_wdog.c
+++ b/drivers/watchdog/sb_wdog.c
@@ -164,7 +164,7 @@ static ssize_t sbwdog_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long sbwdog_ioctl(struct file *file, unsigned int cmd,
+static int sbwdog_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	int ret = -ENOTTY;
diff --git a/drivers/watchdog/sbc60xxwdt.c b/drivers/watchdog/sbc60xxwdt.c
index 3266daa..9507175 100644
--- a/drivers/watchdog/sbc60xxwdt.c
+++ b/drivers/watchdog/sbc60xxwdt.c
@@ -225,7 +225,7 @@ static int fop_close(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/sbc7240_wdt.c b/drivers/watchdog/sbc7240_wdt.c
index 67ddeb1..74d648c 100644
--- a/drivers/watchdog/sbc7240_wdt.c
+++ b/drivers/watchdog/sbc7240_wdt.c
@@ -168,7 +168,7 @@ static const struct watchdog_info ident = {
 };
 
 
-static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case WDIOC_GETSUPPORT:
diff --git a/drivers/watchdog/sbc_epx_c3.c b/drivers/watchdog/sbc_epx_c3.c
index e5e470c..a367d9f 100644
--- a/drivers/watchdog/sbc_epx_c3.c
+++ b/drivers/watchdog/sbc_epx_c3.c
@@ -100,7 +100,7 @@ static ssize_t epx_c3_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long epx_c3_ioctl(struct file *file, unsigned int cmd,
+static int epx_c3_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	int options, retval = -EINVAL;
diff --git a/drivers/watchdog/sc1200wdt.c b/drivers/watchdog/sc1200wdt.c
index 23da3cc..0f57878 100644
--- a/drivers/watchdog/sc1200wdt.c
+++ b/drivers/watchdog/sc1200wdt.c
@@ -182,7 +182,7 @@ static int sc1200wdt_open(struct inode *inode, struct file *file)
 }
 
 
-static long sc1200wdt_ioctl(struct file *file, unsigned int cmd,
+static int sc1200wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 						unsigned long arg)
 {
 	int new_timeout;
diff --git a/drivers/watchdog/sc520_wdt.c b/drivers/watchdog/sc520_wdt.c
index a2b6c10..d2851bf 100644
--- a/drivers/watchdog/sc520_wdt.c
+++ b/drivers/watchdog/sc520_wdt.c
@@ -279,7 +279,7 @@ static int fop_close(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/scx200_wdt.c b/drivers/watchdog/scx200_wdt.c
index 9e19a10..8203518 100644
--- a/drivers/watchdog/scx200_wdt.c
+++ b/drivers/watchdog/scx200_wdt.c
@@ -155,7 +155,7 @@ static ssize_t scx200_wdt_write(struct file *file, const char __user *data,
 	return 0;
 }
 
-static long scx200_wdt_ioctl(struct file *file, unsigned int cmd,
+static int scx200_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/shwdt.c b/drivers/watchdog/shwdt.c
index cdc7138..8eebcb3 100644
--- a/drivers/watchdog/shwdt.c
+++ b/drivers/watchdog/shwdt.c
@@ -338,7 +338,7 @@ static int sh_wdt_mmap(struct file *file, struct vm_area_struct *vma)
  * 	Query basic information from the device or ping it, as outlined by the
  * 	watchdog API.
  */
-static long sh_wdt_ioctl(struct file *file, unsigned int cmd,
+static int sh_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int new_heartbeat;
diff --git a/drivers/watchdog/smsc37b787_wdt.c b/drivers/watchdog/smsc37b787_wdt.c
index 988ff1d..09828f1 100644
--- a/drivers/watchdog/smsc37b787_wdt.c
+++ b/drivers/watchdog/smsc37b787_wdt.c
@@ -423,7 +423,7 @@ static ssize_t wb_smsc_wdt_write(struct file *file, const char __user *data,
 
 /* ioctl => control interface */
 
-static long wb_smsc_wdt_ioctl(struct file *file,
+static int wb_smsc_wdt_ioctl(struct inode *inode, struct file *file,
 					unsigned int cmd, unsigned long arg)
 {
 	int new_timeout;
diff --git a/drivers/watchdog/softdog.c b/drivers/watchdog/softdog.c
index c650464..9a2d3fa 100644
--- a/drivers/watchdog/softdog.c
+++ b/drivers/watchdog/softdog.c
@@ -192,7 +192,7 @@ static ssize_t softdog_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long softdog_ioctl(struct file *file, unsigned int cmd,
+static int softdog_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/txx9wdt.c b/drivers/watchdog/txx9wdt.c
index 6adab77..8184c55 100644
--- a/drivers/watchdog/txx9wdt.c
+++ b/drivers/watchdog/txx9wdt.c
@@ -127,7 +127,7 @@ static ssize_t txx9wdt_write(struct file *file, const char __user *data,
 	return len;
 }
 
-static long txx9wdt_ioctl(struct file *file, unsigned int cmd,
+static int txx9wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/w83627hf_wdt.c b/drivers/watchdog/w83627hf_wdt.c
index 69396ad..9ec4bed 100644
--- a/drivers/watchdog/w83627hf_wdt.c
+++ b/drivers/watchdog/w83627hf_wdt.c
@@ -191,7 +191,7 @@ static ssize_t wdt_write(struct file *file, const char __user *buf,
 	return count;
 }
 
-static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/w83697hf_wdt.c b/drivers/watchdog/w83697hf_wdt.c
index 445d30a..b969baa 100644
--- a/drivers/watchdog/w83697hf_wdt.c
+++ b/drivers/watchdog/w83697hf_wdt.c
@@ -229,7 +229,7 @@ static ssize_t wdt_write(struct file *file, const char __user *buf,
 	return count;
 }
 
-static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/w83877f_wdt.c b/drivers/watchdog/w83877f_wdt.c
index 24587d2..36ed0b2 100644
--- a/drivers/watchdog/w83877f_wdt.c
+++ b/drivers/watchdog/w83877f_wdt.c
@@ -242,7 +242,7 @@ static int fop_close(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/w83977f_wdt.c b/drivers/watchdog/w83977f_wdt.c
index 2525da5..ab029dd 100644
--- a/drivers/watchdog/w83977f_wdt.c
+++ b/drivers/watchdog/w83977f_wdt.c
@@ -377,7 +377,7 @@ static struct watchdog_info ident = {
 	.identity = WATCHDOG_NAME,
 };
 
-static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int status;
 	int new_options, retval = -EINVAL;
diff --git a/drivers/watchdog/wafer5823wdt.c b/drivers/watchdog/wafer5823wdt.c
index 68377ae..06e6cae 100644
--- a/drivers/watchdog/wafer5823wdt.c
+++ b/drivers/watchdog/wafer5823wdt.c
@@ -121,7 +121,7 @@ static ssize_t wafwdt_write(struct file *file, const char __user *buf,
 	return count;
 }
 
-static long wafwdt_ioctl(struct file *file, unsigned int cmd,
+static int wafwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int new_timeout;
diff --git a/drivers/watchdog/wdrtas.c b/drivers/watchdog/wdrtas.c
index 5d3b1a8..823ed73 100644
--- a/drivers/watchdog/wdrtas.c
+++ b/drivers/watchdog/wdrtas.c
@@ -305,7 +305,7 @@ out:
  * wdrtas_ioctl implements the watchdog API ioctls
  */
 
-static long wdrtas_ioctl(struct file *file, unsigned int cmd,
+static int wdrtas_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int __user *argp = (void __user *)arg;
diff --git a/drivers/watchdog/wdt.c b/drivers/watchdog/wdt.c
index deeebb2..cfbba80 100644
--- a/drivers/watchdog/wdt.c
+++ b/drivers/watchdog/wdt.c
@@ -349,7 +349,7 @@ static ssize_t wdt_write(struct file *file, const char __user *buf,
  *	querying capabilities and current status.
  */
 
-static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
 	int __user *p = argp;
diff --git a/drivers/watchdog/wdt285.c b/drivers/watchdog/wdt285.c
index db362c3..e799311 100644
--- a/drivers/watchdog/wdt285.c
+++ b/drivers/watchdog/wdt285.c
@@ -132,7 +132,7 @@ static const struct watchdog_info ident = {
 	.identity	= "Footbridge Watchdog",
 };
 
-static long watchdog_ioctl(struct file *file, unsigned int cmd,
+static int watchdog_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	unsigned int new_margin;
diff --git a/drivers/watchdog/wdt977.c b/drivers/watchdog/wdt977.c
index 60e28d4..348674f 100644
--- a/drivers/watchdog/wdt977.c
+++ b/drivers/watchdog/wdt977.c
@@ -351,7 +351,7 @@ static const struct watchdog_info ident = {
  *      according to their available features.
  */
 
-static long wdt977_ioctl(struct file *file, unsigned int cmd,
+static int wdt977_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int status;
diff --git a/drivers/watchdog/wdt_pci.c b/drivers/watchdog/wdt_pci.c
index ed02bdb..2d6a3e5 100644
--- a/drivers/watchdog/wdt_pci.c
+++ b/drivers/watchdog/wdt_pci.c
@@ -403,7 +403,7 @@ static ssize_t wdtpci_write(struct file *file, const char __user *buf,
  *	querying capabilities and current status.
  */
 
-static long wdtpci_ioctl(struct file *file, unsigned int cmd,
+static int wdtpci_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 							unsigned long arg)
 {
 	int new_heartbeat;
diff --git a/fs/bad_inode.c b/fs/bad_inode.c
index 5f1538c..acb7af1 100644
--- a/fs/bad_inode.c
+++ b/fs/bad_inode.c
@@ -61,13 +61,13 @@ static int bad_file_ioctl (struct inode *inode, struct file *filp,
 	return -EIO;
 }
 
-static long bad_file_unlocked_ioctl(struct file *file, unsigned cmd,
+static int bad_file_unlocked_ioctl(struct inode *inode, struct file *file, unsigned cmd,
 			unsigned long arg)
 {
 	return -EIO;
 }
 
-static long bad_file_compat_ioctl(struct file *file, unsigned int cmd,
+static int bad_file_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 			unsigned long arg)
 {
 	return -EIO;
diff --git a/fs/block_dev.c b/fs/block_dev.c
index aff5421..d1384f0 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1150,8 +1150,13 @@ static int blkdev_close(struct inode * inode, struct file * filp)
 	return blkdev_put(bdev);
 }
 
-static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+static int block_ioctl(struct inode *inode, struct file *file, unsigned cmd, unsigned long arg)
 {
+	/*
+	 * NOTE! We ignore the on-disk inode that was passed as
+	 * an argument, and use the "f_mapping->host" inode for
+	 * all block ioctls!
+	 */
 	return blkdev_ioctl(file->f_mapping->host, file, cmd, arg);
 }
 
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 135c965..f46a281 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -95,7 +95,7 @@ extern int 	cifs_setxattr(struct dentry *, const char *, const void *,
 			size_t, int);
 extern ssize_t	cifs_getxattr(struct dentry *, const char *, void *, size_t);
 extern ssize_t	cifs_listxattr(struct dentry *, char *, size_t);
-extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
+extern int cifs_ioctl(struct inode *inode, struct file *filep, unsigned int cmd, unsigned long arg);
 
 #ifdef CONFIG_CIFS_EXPERIMENTAL
 extern const struct export_operations cifs_export_ops;
diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
index 0088a5b..c6b9fa4 100644
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -30,9 +30,8 @@
 
 #define CIFS_IOC_CHECKUMOUNT _IO(0xCF, 2)
 
-long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
+int cifs_ioctl(struct inode *inode, struct file *filep, unsigned int command, unsigned long arg)
 {
-	struct inode *inode = filep->f_dentry->d_inode;
 	int rc = -ENOTTY; /* strange error - but the precedent */
 	int xid;
 	struct cifs_sb_info *cifs_sb;
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index 5235c67..d3a3093 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -2804,7 +2804,8 @@ asmlinkage long compat_sys_ioctl(unsigned int fd, unsigned int cmd,
 
 	default:
 		if (filp->f_op && filp->f_op->compat_ioctl) {
-			error = filp->f_op->compat_ioctl(filp, cmd, arg);
+			struct inode *inode = filp->f_dentry->d_inode;
+			error = filp->f_op->compat_ioctl(inode, filp, cmd, arg);
 			if (error != -ENOIOCTLCMD)
 				goto out_fput;
 		}
diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index 47d88da..6924f85 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -138,8 +138,8 @@ int __ext2_write_begin(struct file *file, struct address_space *mapping,
 		struct page **pagep, void **fsdata);
 
 /* ioctl.c */
-extern long ext2_ioctl(struct file *, unsigned int, unsigned long);
-extern long ext2_compat_ioctl(struct file *, unsigned int, unsigned long);
+extern int ext2_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
+extern int ext2_compat_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 
 /* namei.c */
 struct dentry *ext2_get_parent(struct dentry *child);
diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
index de876fa..ba84585 100644
--- a/fs/ext2/ioctl.c
+++ b/fs/ext2/ioctl.c
@@ -18,9 +18,8 @@
 #include <asm/uaccess.h>
 
 
-long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int ext2_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
 	struct ext2_inode_info *ei = EXT2_I(inode);
 	unsigned int flags;
 	unsigned short rsv_window_size;
@@ -156,7 +155,7 @@ setflags_out:
 }
 
 #ifdef CONFIG_COMPAT
-long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int ext2_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	/* These are just misnamed, they actually get/put from/to user an int */
 	switch (cmd) {
@@ -175,6 +174,6 @@ long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	default:
 		return -ENOIOCTLCMD;
 	}
-	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
+	return ext2_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
 }
 #endif
diff --git a/fs/ext3/ioctl.c b/fs/ext3/ioctl.c
index 0d0c701..7cf4617 100644
--- a/fs/ext3/ioctl.c
+++ b/fs/ext3/ioctl.c
@@ -294,9 +294,8 @@ group_add_out:
 }
 
 #ifdef CONFIG_COMPAT
-long ext3_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int ext3_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	int ret;
 
 	/* These are just misnamed, they actually get/put from/to user an int */
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 2950032..4bee000 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1079,8 +1079,8 @@ extern int ext4_block_truncate_page(handle_t *handle,
 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct page *page);
 
 /* ioctl.c */
-extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
-extern long ext4_compat_ioctl (struct file *, unsigned int, unsigned long);
+extern int ext4_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
+extern int ext4_compat_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 
 /* migrate.c */
 extern int ext4_ext_migrate(struct inode *, struct file *, unsigned int,
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 7a6c2f1..f72db70 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -18,9 +18,8 @@
 #include "ext4_jbd2.h"
 #include "ext4.h"
 
-long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int ext4_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	unsigned int flags;
 	unsigned short rsv_window_size;
@@ -275,7 +274,7 @@ setversion_out:
 }
 
 #ifdef CONFIG_COMPAT
-long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int ext4_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	/* These are just misnamed, they actually get/put from/to user an int */
 	switch (cmd) {
@@ -316,6 +315,6 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	default:
 		return -ENOIOCTLCMD;
 	}
-	return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
+	return ext4_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
 }
 #endif
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index cd4a016..32c94b1 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -796,10 +796,9 @@ static int fat_dir_ioctl(struct inode *inode, struct file *filp,
 
 FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
 
-static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
+static int fat_compat_dir_ioctl(struct inode *inode, struct file *filp, unsigned cmd,
 				 unsigned long arg)
 {
-	struct inode *inode = filp->f_path.dentry->d_inode;
 	struct compat_dirent __user *d1 = compat_ptr(arg);
 	int short_only, both;
 
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
index e9a366d..b7bf87c 100644
--- a/fs/gfs2/ops_file.c
+++ b/fs/gfs2/ops_file.c
@@ -289,7 +289,7 @@ static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
 	return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA);
 }
 
-static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int gfs2_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	switch(cmd) {
 	case FS_IOC_GETFLAGS:
diff --git a/fs/inotify_user.c b/fs/inotify_user.c
index 6024942..9cfde4e 100644
--- a/fs/inotify_user.c
+++ b/fs/inotify_user.c
@@ -533,7 +533,7 @@ static int inotify_release(struct inode *ignored, struct file *file)
 	return 0;
 }
 
-static long inotify_ioctl(struct file *file, unsigned int cmd,
+static int inotify_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 			  unsigned long arg)
 {
 	struct inotify_device *dev;
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 7db32b3..2adb993 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -31,20 +31,20 @@
 static long vfs_ioctl(struct file *filp, unsigned int cmd,
 		      unsigned long arg)
 {
+	struct inode *inode;
 	int error = -ENOTTY;
 
 	if (!filp->f_op)
 		goto out;
 
+	inode = filp->f_path.dentry->d_inode;
 	if (filp->f_op->unlocked_ioctl) {
-		error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
+		error = filp->f_op->unlocked_ioctl(inode, filp, cmd, arg);
 		if (error == -ENOIOCTLCMD)
 			error = -EINVAL;
-		goto out;
 	} else if (filp->f_op->ioctl) {
 		lock_kernel();
-		error = filp->f_op->ioctl(filp->f_path.dentry->d_inode,
-					  filp, cmd, arg);
+		error = filp->f_op->ioctl(inode, filp, cmd, arg);
 		unlock_kernel();
 	}
 
diff --git a/fs/jffs2/ioctl.c b/fs/jffs2/ioctl.c
index 9d41f43..80aa967 100644
--- a/fs/jffs2/ioctl.c
+++ b/fs/jffs2/ioctl.c
@@ -12,7 +12,7 @@
 #include <linux/fs.h>
 #include "nodelist.h"
 
-long jffs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int jffs2_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	/* Later, this will provide for lsattr.jffs2 and chattr.jffs2, which
 	   will include compression support etc. */
diff --git a/fs/jffs2/os-linux.h b/fs/jffs2/os-linux.h
index 5e194a5..7ef2c62 100644
--- a/fs/jffs2/os-linux.h
+++ b/fs/jffs2/os-linux.h
@@ -167,7 +167,7 @@ int jffs2_fsync(struct file *, struct dentry *, int);
 int jffs2_do_readpage_unlock (struct inode *inode, struct page *pg);
 
 /* ioctl.c */
-long jffs2_ioctl(struct file *, unsigned int, unsigned long);
+int jffs2_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 
 /* symlink.c */
 extern const struct inode_operations jffs2_symlink_inode_operations;
diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
index afe222b..0fdf047 100644
--- a/fs/jfs/ioctl.c
+++ b/fs/jfs/ioctl.c
@@ -52,9 +52,8 @@ static long jfs_map_ext2(unsigned long flags, int from)
 }
 
 
-long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int jfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
 	struct jfs_inode_info *jfs_inode = JFS_IP(inode);
 	unsigned int flags;
 
@@ -129,7 +128,7 @@ setflags_out:
 }
 
 #ifdef CONFIG_COMPAT
-long jfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int jfs_compat_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	/* While these ioctl numbers defined with 'long' and have different
 	 * numbers than the 64bit ABI,
@@ -143,6 +142,6 @@ long jfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		cmd = JFS_IOC_SETFLAGS;
 		break;
 	}
-	return jfs_ioctl(filp, cmd, arg);
+	return jfs_ioctl(inode, filp, cmd, arg);
 }
 #endif
diff --git a/fs/jfs/jfs_inode.h b/fs/jfs/jfs_inode.h
index adb2faf..a94ca32 100644
--- a/fs/jfs/jfs_inode.h
+++ b/fs/jfs/jfs_inode.h
@@ -22,8 +22,8 @@ struct fid;
 
 extern struct inode *ialloc(struct inode *, umode_t);
 extern int jfs_fsync(struct file *, struct dentry *, int);
-extern long jfs_ioctl(struct file *, unsigned int, unsigned long);
-extern long jfs_compat_ioctl(struct file *, unsigned int, unsigned long);
+extern int jfs_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
+extern int jfs_compat_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 extern struct inode *jfs_iget(struct super_block *, unsigned long);
 extern int jfs_commit_inode(struct inode *, int);
 extern int jfs_write_inode(struct inode*, int);
diff --git a/fs/ncpfs/ioctl.c b/fs/ncpfs/ioctl.c
index 3a97c95..75c3c29 100644
--- a/fs/ncpfs/ioctl.c
+++ b/fs/ncpfs/ioctl.c
@@ -874,9 +874,8 @@ int ncp_ioctl(struct inode *inode, struct file *filp,
 }
 
 #ifdef CONFIG_COMPAT
-long ncp_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int ncp_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	int ret;
 
 	lock_kernel();
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index 7b142f0..bf5c6a2 100644
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c
@@ -109,9 +109,8 @@ bail:
 	return status;
 }
 
-long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+int ocfs2_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_path.dentry->d_inode;
 	unsigned int flags;
 	int new_clusters;
 	int status;
@@ -168,7 +167,7 @@ long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 }
 
 #ifdef CONFIG_COMPAT
-long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+int ocfs2_compat_ioctl(struct inode *inode, struct file *file, unsigned cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case OCFS2_IOC32_GETFLAGS:
@@ -189,6 +188,6 @@ long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 		return -ENOIOCTLCMD;
 	}
 
-	return ocfs2_ioctl(file, cmd, arg);
+	return ocfs2_ioctl(inode, file, cmd, arg);
 }
 #endif
diff --git a/fs/ocfs2/ioctl.h b/fs/ocfs2/ioctl.h
index cf9a5ee..0632b05 100644
--- a/fs/ocfs2/ioctl.h
+++ b/fs/ocfs2/ioctl.h
@@ -10,7 +10,7 @@
 #ifndef OCFS2_IOCTL_H
 #define OCFS2_IOCTL_H
 
-long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
-long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg);
+int ocfs2_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg);
+int ocfs2_compat_ioctl(struct inode *inode, struct file *file, unsigned cmd, unsigned long arg);
 
 #endif /* OCFS2_IOCTL_H */
diff --git a/fs/pipe.c b/fs/pipe.c
index fcba654..8765108 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -577,9 +577,8 @@ bad_pipe_w(struct file *filp, const char __user *buf, size_t count,
 	return -EBADF;
 }
 
-static long pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int pipe_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = filp->f_path.dentry->d_inode;
 	struct pipe_inode_info *pipe;
 	int count, buf, nrbufs;
 
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 8bb03f0..711bb4f 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -239,11 +239,11 @@ static unsigned int proc_reg_poll(struct file *file, struct poll_table_struct *p
 	return rv;
 }
 
-static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int proc_reg_unlocked_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
 	long rv = -ENOTTY;
-	long (*unlocked_ioctl)(struct file *, unsigned int, unsigned long);
+	int (*unlocked_ioctl)(struct inode *, struct file *, unsigned int, unsigned long);
 	int (*ioctl)(struct inode *, struct file *, unsigned int, unsigned long);
 
 	spin_lock(&pde->pde_unload_lock);
@@ -257,12 +257,12 @@ static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigne
 	spin_unlock(&pde->pde_unload_lock);
 
 	if (unlocked_ioctl) {
-		rv = unlocked_ioctl(file, cmd, arg);
+		rv = unlocked_ioctl(inode, file, cmd, arg);
 		if (rv == -ENOIOCTLCMD)
 			rv = -EINVAL;
 	} else if (ioctl) {
 		lock_kernel();
-		rv = ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
+		rv = ioctl(inode, file, cmd, arg);
 		unlock_kernel();
 	}
 
@@ -271,11 +271,11 @@ static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigne
 }
 
 #ifdef CONFIG_COMPAT
-static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int proc_reg_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
 	long rv = -ENOTTY;
-	long (*compat_ioctl)(struct file *, unsigned int, unsigned long);
+	int (*compat_ioctl)(struct inode *, struct file *, unsigned int, unsigned long);
 
 	spin_lock(&pde->pde_unload_lock);
 	if (!pde->proc_fops) {
@@ -287,7 +287,7 @@ static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned
 	spin_unlock(&pde->pde_unload_lock);
 
 	if (compat_ioctl)
-		rv = compat_ioctl(file, cmd, arg);
+		rv = compat_ioctl(inode, file, cmd, arg);
 
 	pde_users_dec(pde);
 	return rv;
diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c
index 8303320..d85fe0d 100644
--- a/fs/reiserfs/ioctl.c
+++ b/fs/reiserfs/ioctl.c
@@ -115,10 +115,9 @@ setversion_out:
 }
 
 #ifdef CONFIG_COMPAT
-long reiserfs_compat_ioctl(struct file *file, unsigned int cmd,
+int reiserfs_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 				unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	int ret;
 
 	/* These are just misnamed, they actually get/put from/to user an int */
diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c
index 5e82cff..08cf595 100644
--- a/fs/ubifs/ioctl.c
+++ b/fs/ubifs/ioctl.c
@@ -145,10 +145,9 @@ out_unlock:
 	return err;
 }
 
-long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int ubifs_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	int flags, err;
-	struct inode *inode = file->f_path.dentry->d_inode;
 
 	switch (cmd) {
 	case FS_IOC_GETFLAGS:
@@ -187,7 +186,7 @@ long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 }
 
 #ifdef CONFIG_COMPAT
-long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int ubifs_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case FS_IOC32_GETFLAGS:
@@ -199,6 +198,6 @@ long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	default:
 		return -ENOIOCTLCMD;
 	}
-	return ubifs_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+	return ubifs_ioctl(inode, file, cmd, (unsigned long)compat_ptr(arg));
 }
 #endif
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index d7f706f..d82737e 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1639,10 +1639,10 @@ int ubifs_recover_size(struct ubifs_info *c);
 void ubifs_destroy_size_tree(struct ubifs_info *c);
 
 /* ioctl.c */
-long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+int ubifs_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 void ubifs_set_inode_flags(struct inode *inode);
 #ifdef CONFIG_COMPAT
-long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+int ubifs_compat_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 #endif
 
 /* compressor.c */
diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c
index 5311c1a..a4c1d10 100644
--- a/fs/xfs/linux-2.6/xfs_file.c
+++ b/fs/xfs/linux-2.6/xfs_file.c
@@ -376,14 +376,14 @@ xfs_file_mmap(
 	return 0;
 }
 
-STATIC long
+STATIC int
 xfs_file_ioctl(
+	struct inode	*inode,
 	struct file	*filp,
 	unsigned int	cmd,
 	unsigned long	p)
 {
 	int		error;
-	struct inode	*inode = filp->f_path.dentry->d_inode;
 
 	error = xfs_ioctl(XFS_I(inode), filp, 0, cmd, (void __user *)p);
 	xfs_iflags_set(XFS_I(inode), XFS_IMODIFIED);
@@ -397,14 +397,14 @@ xfs_file_ioctl(
 	return error;
 }
 
-STATIC long
+STATIC int
 xfs_file_ioctl_invis(
+	struct inode	*inode,
 	struct file	*filp,
 	unsigned int	cmd,
 	unsigned long	p)
 {
 	int		error;
-	struct inode	*inode = filp->f_path.dentry->d_inode;
 
 	error = xfs_ioctl(XFS_I(inode), filp, IO_INVIS, cmd, (void __user *)p);
 	xfs_iflags_set(XFS_I(inode), XFS_IMODIFIED);
diff --git a/fs/xfs/linux-2.6/xfs_ioctl32.c b/fs/xfs/linux-2.6/xfs_ioctl32.c
index a4b254e..dfe42ab 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl32.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl32.c
@@ -469,8 +469,9 @@ xfs_compat_ioctl(
 	return error;
 }
 
-long
+int
 xfs_file_compat_ioctl(
+	struct inode		*inode,
 	struct file		*file,
 	unsigned		cmd,
 	unsigned long		arg)
@@ -478,8 +479,9 @@ xfs_file_compat_ioctl(
 	return xfs_compat_ioctl(0, file, cmd, arg);
 }
 
-long
+int
 xfs_file_compat_invis_ioctl(
+	struct inode		*inode,
 	struct file		*file,
 	unsigned		cmd,
 	unsigned long		arg)
diff --git a/fs/xfs/linux-2.6/xfs_ioctl32.h b/fs/xfs/linux-2.6/xfs_ioctl32.h
index 02de6e6..7e64783 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl32.h
+++ b/fs/xfs/linux-2.6/xfs_ioctl32.h
@@ -18,7 +18,7 @@
 #ifndef __XFS_IOCTL32_H__
 #define __XFS_IOCTL32_H__
 
-extern long xfs_file_compat_ioctl(struct file *, unsigned, unsigned long);
-extern long xfs_file_compat_invis_ioctl(struct file *, unsigned, unsigned long);
+extern int xfs_file_compat_ioctl(struct inode *inode, struct file *, unsigned, unsigned long);
+extern int xfs_file_compat_invis_ioctl(struct inode *inode, struct file *, unsigned, unsigned long);
 
 #endif /* __XFS_IOCTL32_H__ */
diff --git a/include/linux/ext3_fs.h b/include/linux/ext3_fs.h
index 80171ee..c30e0ab 100644
--- a/include/linux/ext3_fs.h
+++ b/include/linux/ext3_fs.h
@@ -841,7 +841,7 @@ extern void ext3_set_aops(struct inode *inode);
 /* ioctl.c */
 extern int ext3_ioctl (struct inode *, struct file *, unsigned int,
 		       unsigned long);
-extern long ext3_compat_ioctl (struct file *, unsigned int, unsigned long);
+extern int ext3_compat_ioctl (struct inode *, struct file *, unsigned int, unsigned long);
 
 /* namei.c */
 extern int ext3_orphan_add(handle_t *, struct inode *);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 580b513..9bcfbcd 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1211,8 +1211,8 @@ struct block_device_operations {
 	int (*open) (struct inode *, struct file *);
 	int (*release) (struct inode *, struct file *);
 	int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
-	long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
-	long (*compat_ioctl) (struct file *, unsigned, unsigned long);
+	int (*unlocked_ioctl) (struct inode *, struct file *, unsigned, unsigned long);
+	int (*compat_ioctl) (struct inode *, struct file *, unsigned, unsigned long);
 	int (*direct_access) (struct block_device *, sector_t,
 						void **, unsigned long *);
 	int (*media_changed) (struct gendisk *);
@@ -1242,8 +1242,8 @@ struct file_operations {
 	int (*readdir) (struct file *, void *, filldir_t);
 	unsigned int (*poll) (struct file *, struct poll_table_struct *);
 	int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
-	long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
-	long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
+	int (*unlocked_ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
+	int (*compat_ioctl) (struct inode *,struct file *, unsigned int, unsigned long);
 	int (*mmap) (struct file *, struct vm_area_struct *);
 	int (*open) (struct inode *, struct file *);
 	int (*flush) (struct file *, fl_owner_t id);
@@ -1656,7 +1656,7 @@ extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
 extern int blkdev_driver_ioctl(struct inode *inode, struct file *file,
 			       struct gendisk *disk, unsigned cmd,
 			       unsigned long arg);
-extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
+extern int compat_blkdev_ioctl(struct inode *inode, struct file *, unsigned, unsigned long);
 extern int blkdev_get(struct block_device *, mode_t, unsigned);
 extern int blkdev_put(struct block_device *);
 extern int bd_claim(struct block_device *, void *);
diff --git a/include/linux/ncp_fs.h b/include/linux/ncp_fs.h
index 9f2d763..af7d026 100644
--- a/include/linux/ncp_fs.h
+++ b/include/linux/ncp_fs.h
@@ -211,7 +211,7 @@ void ncp_date_unix2dos(int unix_date, __le16 * time, __le16 * date);
 
 /* linux/fs/ncpfs/ioctl.c */
 int ncp_ioctl(struct inode *, struct file *, unsigned int, unsigned long);
-long ncp_compat_ioctl(struct file *, unsigned int, unsigned long);
+int ncp_compat_ioctl(struct inode *inode, struct file *, unsigned int, unsigned long);
 
 /* linux/fs/ncpfs/sock.c */
 int ncp_request2(struct ncp_server *server, int function,
diff --git a/include/linux/reiserfs_fs.h b/include/linux/reiserfs_fs.h
index e9963af..3422037 100644
--- a/include/linux/reiserfs_fs.h
+++ b/include/linux/reiserfs_fs.h
@@ -2174,7 +2174,7 @@ __u32 r5_hash(const signed char *msg, int len);
 /* prototypes from ioctl.c */
 int reiserfs_ioctl(struct inode *inode, struct file *filp,
 		   unsigned int cmd, unsigned long arg);
-long reiserfs_compat_ioctl(struct file *filp,
+int reiserfs_compat_ioctl(struct inode *inode, struct file *filp,
 		   unsigned int cmd, unsigned long arg);
 int reiserfs_unpack(struct inode *inode, struct file *filp);
 
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 0cbec74..bdb65a2 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -365,7 +365,7 @@ extern const struct file_operations tty_ldiscs_proc_fops;
 extern void tty_wakeup(struct tty_struct *tty);
 extern void tty_ldisc_flush(struct tty_struct *tty);
 
-extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+extern int tty_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 			unsigned int cmd, unsigned long arg);
 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
diff --git a/include/linux/wanrouter.h b/include/linux/wanrouter.h
index e0aa396..82d2547 100644
--- a/include/linux/wanrouter.h
+++ b/include/linux/wanrouter.h
@@ -522,7 +522,7 @@ extern int wanrouter_proc_init(void);
 extern void wanrouter_proc_cleanup(void);
 extern int wanrouter_proc_add(struct wan_device *wandev);
 extern int wanrouter_proc_delete(struct wan_device *wandev);
-extern long wanrouter_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+extern int wanrouter_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 
 /* Public Data */
 /* list of registered devices */
diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index dc64046..9ab9474 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -286,7 +286,7 @@ int v4l_compat_translate_ioctl(struct inode *inode, struct file *file,
 #endif
 
 /* 32 Bits compatibility layer for 64 bits processors */
-extern long v4l_compat_ioctl32(struct file *file, unsigned int cmd,
+extern int v4l_compat_ioctl32(struct inode *inode, struct file *file, unsigned int cmd,
 				unsigned long arg);
 
 extern int video_ioctl2(struct inode *inode, struct file *file,
diff --git a/kernel/power/user.c b/kernel/power/user.c
index a6332a3..6f8b19d 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -187,7 +187,7 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
 	return res;
 }
 
-static long snapshot_ioctl(struct file *filp, unsigned int cmd,
+static int snapshot_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
 							unsigned long arg)
 {
 	int error = 0;
diff --git a/net/irda/irnet/irnet_ppp.c b/net/irda/irnet/irnet_ppp.c
index 6d8ae03..ae45f37 100644
--- a/net/irda/irnet/irnet_ppp.c
+++ b/net/irda/irnet/irnet_ppp.c
@@ -631,8 +631,9 @@ dev_irnet_poll(struct file *	file,
  * This is the way pppd configure us and control us while the PPP
  * instance is active.
  */
-static long
+static int
 dev_irnet_ioctl(
+		struct inode *	inode,
 		struct file *	file,
 		unsigned int	cmd,
 		unsigned long	arg)
diff --git a/net/irda/irnet/irnet_ppp.h b/net/irda/irnet/irnet_ppp.h
index d9f8bd4..44bd8ec 100644
--- a/net/irda/irnet/irnet_ppp.h
+++ b/net/irda/irnet/irnet_ppp.h
@@ -76,8 +76,9 @@ static ssize_t
 static unsigned int
 	dev_irnet_poll(struct file *,
 		       poll_table *);
-static long
-	dev_irnet_ioctl(struct file *,
+static int
+	dev_irnet_ioctl(struct inode *,
+			struct file *,
 			unsigned int,
 			unsigned long);
 /* ------------------------ PPP INTERFACE ------------------------ */
diff --git a/net/socket.c b/net/socket.c
index 8ef8ba8..5d6824b 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -107,9 +107,9 @@ static int sock_mmap(struct file *file, struct vm_area_struct *vma);
 static int sock_close(struct inode *inode, struct file *file);
 static unsigned int sock_poll(struct file *file,
 			      struct poll_table_struct *wait);
-static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+static int sock_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 #ifdef CONFIG_COMPAT
-static long compat_sock_ioctl(struct file *file,
+static int compat_sock_ioctl(struct inode *inode, struct file *file,
 			      unsigned int cmd, unsigned long arg);
 #endif
 static int sock_fasync(int fd, struct file *filp, int on);
@@ -850,7 +850,7 @@ EXPORT_SYMBOL(dlci_ioctl_set);
  *	what to do with it - that's up to the protocol still.
  */
 
-static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+static int sock_ioctl(struct inode *inode, struct file *file, unsigned cmd, unsigned long arg)
 {
 	struct socket *sock;
 	struct sock *sk;
@@ -2316,7 +2316,7 @@ void socket_seq_show(struct seq_file *seq)
 #endif				/* CONFIG_PROC_FS */
 
 #ifdef CONFIG_COMPAT
-static long compat_sock_ioctl(struct file *file, unsigned cmd,
+static int compat_sock_ioctl(struct inode *inode, struct file *file, unsigned cmd,
 			      unsigned long arg)
 {
 	struct socket *sock = file->private_data;
diff --git a/net/wanrouter/wanmain.c b/net/wanrouter/wanmain.c
index 7f07152..2974428 100644
--- a/net/wanrouter/wanmain.c
+++ b/net/wanrouter/wanmain.c
@@ -349,9 +349,8 @@ __be16 wanrouter_type_trans(struct sk_buff *skb, struct net_device *dev)
  *	o execute requested action or pass command to the device driver
  */
 
-long wanrouter_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+int wanrouter_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	int err = 0;
 	struct proc_dir_entry *dent;
 	struct wan_device *wandev;
diff --git a/sound/core/control.c b/sound/core/control.c
index 281b2e2..f10a3f0 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1149,7 +1149,7 @@ static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
 	return err;
 }
 
-static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_ctl_file *ctl;
 	struct snd_card *card;
diff --git a/sound/core/control_compat.c b/sound/core/control_compat.c
index 6101259..0af5c5b 100644
--- a/sound/core/control_compat.c
+++ b/sound/core/control_compat.c
@@ -390,7 +390,7 @@ enum {
 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 };
 
-static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
+static inline int snd_ctl_ioctl_compat(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_ctl_file *ctl;
 	struct snd_kctl_ioctl *p;
@@ -412,7 +412,7 @@ static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, uns
 	case SNDRV_CTL_IOCTL_TLV_READ:
 	case SNDRV_CTL_IOCTL_TLV_WRITE:
 	case SNDRV_CTL_IOCTL_TLV_COMMAND:
-		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
+		return snd_ctl_ioctl(inode, file, cmd, (unsigned long)argp);
 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
 		return snd_ctl_elem_list_compat(ctl->card, argp);
 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c
index 6d6589f..7518eaa 100644
--- a/sound/core/hwdep.c
+++ b/sound/core/hwdep.c
@@ -231,7 +231,7 @@ static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
 	return 0;
 }
 
-static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
+static int snd_hwdep_ioctl(struct inode *inode, struct file * file, unsigned int cmd,
 			    unsigned long arg)
 {
 	struct snd_hwdep *hw = file->private_data;
diff --git a/sound/core/hwdep_compat.c b/sound/core/hwdep_compat.c
index 3827c0c..3c7cc2a 100644
--- a/sound/core/hwdep_compat.c
+++ b/sound/core/hwdep_compat.c
@@ -59,7 +59,7 @@ enum {
 	SNDRV_HWDEP_IOCTL_DSP_LOAD32   = _IOW('H', 0x03, struct snd_hwdep_dsp_image32)
 };
 
-static long snd_hwdep_ioctl_compat(struct file * file, unsigned int cmd,
+static int snd_hwdep_ioctl_compat(struct inode *inode, struct file * file, unsigned int cmd,
 				   unsigned long arg)
 {
 	struct snd_hwdep *hw = file->private_data;
@@ -68,7 +68,7 @@ static long snd_hwdep_ioctl_compat(struct file * file, unsigned int cmd,
 	case SNDRV_HWDEP_IOCTL_PVERSION:
 	case SNDRV_HWDEP_IOCTL_INFO:
 	case SNDRV_HWDEP_IOCTL_DSP_STATUS:
-		return snd_hwdep_ioctl(file, cmd, (unsigned long)argp);
+		return snd_hwdep_ioctl(inode, file, cmd, (unsigned long)argp);
 	case SNDRV_HWDEP_IOCTL_DSP_LOAD32:
 		return snd_hwdep_dsp_load_compat(hw, argp);
 	}
diff --git a/sound/core/info.c b/sound/core/info.c
index c67773a..5f8e1e9 100644
--- a/sound/core/info.c
+++ b/sound/core/info.c
@@ -465,7 +465,7 @@ static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait)
 	return mask;
 }
 
-static long snd_info_entry_ioctl(struct file *file, unsigned int cmd,
+static int snd_info_entry_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 				unsigned long arg)
 {
 	struct snd_info_private_data *data;
diff --git a/sound/core/init.c b/sound/core/init.c
index df46bbc..82323a2 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -275,7 +275,7 @@ static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
 	return POLLERR | POLLNVAL;
 }
 
-static long snd_disconnect_ioctl(struct file *file,
+static int snd_disconnect_ioctl(struct inode *inode, struct file *file,
 				 unsigned int cmd, unsigned long arg)
 {
 	return -ENODEV;
diff --git a/sound/core/oss/mixer_oss.c b/sound/core/oss/mixer_oss.c
index 581aa2c..273f177 100644
--- a/sound/core/oss/mixer_oss.c
+++ b/sound/core/oss/mixer_oss.c
@@ -359,7 +359,7 @@ static int snd_mixer_oss_ioctl1(struct snd_mixer_oss_file *fmixer, unsigned int
 	return -ENXIO;
 }
 
-static long snd_mixer_oss_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_mixer_oss_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	return snd_mixer_oss_ioctl1((struct snd_mixer_oss_file *) file->private_data, cmd, arg);
 }
diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index 4c601b1..229513c 100644
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -2428,7 +2428,7 @@ static int snd_pcm_oss_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static long snd_pcm_oss_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_pcm_oss_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_pcm_oss_file *pcm_oss_file;
 	int __user *p = (int __user *)arg;
diff --git a/sound/core/pcm_compat.c b/sound/core/pcm_compat.c
index 49aa693..f480fda 100644
--- a/sound/core/pcm_compat.c
+++ b/sound/core/pcm_compat.c
@@ -460,7 +460,7 @@ enum {
 
 };
 
-static long snd_pcm_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_pcm_ioctl_compat(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_pcm_file *pcm_file;
 	struct snd_pcm_substream *substream;
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index c49b9d9..4c703aa 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -2726,7 +2726,7 @@ static int snd_pcm_capture_ioctl1(struct file *file,
 	return snd_pcm_common_ioctl1(file, substream, cmd, arg);
 }
 
-static long snd_pcm_playback_ioctl(struct file *file, unsigned int cmd,
+static int snd_pcm_playback_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 				   unsigned long arg)
 {
 	struct snd_pcm_file *pcm_file;
@@ -2740,7 +2740,7 @@ static long snd_pcm_playback_ioctl(struct file *file, unsigned int cmd,
 				       (void __user *)arg);
 }
 
-static long snd_pcm_capture_ioctl(struct file *file, unsigned int cmd,
+static int snd_pcm_capture_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 				  unsigned long arg)
 {
 	struct snd_pcm_file *pcm_file;
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index f7ea728..8c103ca 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -687,7 +687,7 @@ static int snd_rawmidi_input_status(struct snd_rawmidi_substream *substream,
 	return 0;
 }
 
-static long snd_rawmidi_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_rawmidi_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_rawmidi_file *rfile;
 	void __user *argp = (void __user *)arg;
diff --git a/sound/core/rawmidi_compat.c b/sound/core/rawmidi_compat.c
index 5268c1f..2764275 100644
--- a/sound/core/rawmidi_compat.c
+++ b/sound/core/rawmidi_compat.c
@@ -99,7 +99,7 @@ enum {
 	SNDRV_RAWMIDI_IOCTL_STATUS32 = _IOWR('W', 0x20, struct snd_rawmidi_status32),
 };
 
-static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_rawmidi_ioctl_compat(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_rawmidi_file *rfile;
 	void __user *argp = compat_ptr(arg);
@@ -110,7 +110,7 @@ static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsign
 	case SNDRV_RAWMIDI_IOCTL_INFO:
 	case SNDRV_RAWMIDI_IOCTL_DROP:
 	case SNDRV_RAWMIDI_IOCTL_DRAIN:
-		return snd_rawmidi_ioctl(file, cmd, (unsigned long)argp);
+		return snd_rawmidi_ioctl(inode, file, cmd, (unsigned long)argp);
 	case SNDRV_RAWMIDI_IOCTL_PARAMS32:
 		return snd_rawmidi_ioctl_params_compat(rfile, argp);
 	case SNDRV_RAWMIDI_IOCTL_STATUS32:
diff --git a/sound/core/seq/oss/seq_oss.c b/sound/core/seq/oss/seq_oss.c
index 777796e..b1fd18e 100644
--- a/sound/core/seq/oss/seq_oss.c
+++ b/sound/core/seq/oss/seq_oss.c
@@ -63,7 +63,7 @@ static int odev_open(struct inode *inode, struct file *file);
 static int odev_release(struct inode *inode, struct file *file);
 static ssize_t odev_read(struct file *file, char __user *buf, size_t count, loff_t *offset);
 static ssize_t odev_write(struct file *file, const char __user *buf, size_t count, loff_t *offset);
-static long odev_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+static int odev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
 static unsigned int odev_poll(struct file *file, poll_table * wait);
 
 
@@ -178,8 +178,8 @@ odev_write(struct file *file, const char __user *buf, size_t count, loff_t *offs
 	return snd_seq_oss_write(dp, buf, count, file);
 }
 
-static long
-odev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int
+odev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct seq_oss_devinfo *dp;
 	dp = file->private_data;
diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 7a1545d..d9ebb9d 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -2191,7 +2191,7 @@ static int snd_seq_do_ioctl(struct snd_seq_client *client, unsigned int cmd,
 }
 
 
-static long snd_seq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_seq_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_seq_client *client = file->private_data;
 
diff --git a/sound/core/seq/seq_compat.c b/sound/core/seq/seq_compat.c
index 9628c06..f1a7060 100644
--- a/sound/core/seq/seq_compat.c
+++ b/sound/core/seq/seq_compat.c
@@ -87,7 +87,7 @@ enum {
 	SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT32 = _IOWR('S', 0x52, struct snd_seq_port_info32),
 };
 
-static long snd_seq_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_seq_ioctl_compat(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_seq_client *client = file->private_data;
 	void __user *argp = compat_ptr(arg);
diff --git a/sound/core/timer.c b/sound/core/timer.c
index 0af337e..f505d69 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -1756,7 +1756,7 @@ enum {
 	SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
 };
 
-static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
+static int snd_timer_user_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 				 unsigned long arg)
 {
 	struct snd_timer_user *tu;
diff --git a/sound/core/timer_compat.c b/sound/core/timer_compat.c
index 5512f53..2dc4785 100644
--- a/sound/core/timer_compat.c
+++ b/sound/core/timer_compat.c
@@ -93,7 +93,7 @@ enum {
 	SNDRV_TIMER_IOCTL_STATUS32 = _IOW('T', 0x14, struct snd_timer_status32),
 };
 
-static long snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
+static int snd_timer_user_ioctl_compat(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = compat_ptr(arg);
 
@@ -114,7 +114,7 @@ static long snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd, uns
 	case SNDRV_TIMER_IOCTL_PAUSE:
 	case SNDRV_TIMER_IOCTL_PAUSE_OLD:
 	case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
-		return snd_timer_user_ioctl(file, cmd, (unsigned long)argp);
+		return snd_timer_user_ioctl(inode, file, cmd, (unsigned long)argp);
 	case SNDRV_TIMER_IOCTL_INFO32:
 		return snd_timer_user_info_compat(file, argp);
 	case SNDRV_TIMER_IOCTL_STATUS32:
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 7dd9b0b..51368d7 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -66,7 +66,7 @@ static __read_mostly struct preempt_ops kvm_preempt_ops;
 
 struct dentry *kvm_debugfs_dir;
 
-static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
+static int kvm_vcpu_ioctl(struct inode *inode, struct file *file, unsigned int ioctl,
 			   unsigned long arg);
 
 bool kvm_rebooting;
@@ -1112,7 +1112,7 @@ static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
 	return 0;
 }
 
-static long kvm_vcpu_ioctl(struct file *filp,
+static int kvm_vcpu_ioctl(struct inode *inode, struct file *filp,
 			   unsigned int ioctl, unsigned long arg)
 {
 	struct kvm_vcpu *vcpu = filp->private_data;
@@ -1295,7 +1295,7 @@ out:
 	return r;
 }
 
-static long kvm_vm_ioctl(struct file *filp,
+static int kvm_vm_ioctl(struct inode *inode, struct file *filp,
 			   unsigned int ioctl, unsigned long arg)
 {
 	struct kvm *kvm = filp->private_data;
@@ -1415,7 +1415,7 @@ static int kvm_dev_ioctl_create_vm(void)
 	return fd;
 }
 
-static long kvm_dev_ioctl(struct file *filp,
+static int kvm_dev_ioctl(struct inode *inode, struct file *filp,
 			  unsigned int ioctl, unsigned long arg)
 {
 	long r = -EINVAL;

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[David Miller]

From: Paul Mundt <lethal@linux-sh.org>
Date: Thu, 28 Aug 2008 09:32:13 +0900

> On Wed, Aug 27, 2008 at 08:35:44PM +0300, Adrian Bunk wrote:
> > CONFIG_DEBUG_STACKOVERFLOW should give you the same information, and if
> > wanted with an arbitrary limit.
>
> In some cases, yes. In the CONFIG_DEBUG_STACKOVERFLOW case the check is
> only performed from do_IRQ(), which is sporadic at best, especially on
> tickless. While it catches some things, it's not a complete solution in
> and of iteslf.

BTW, on sparc64 we have a stack overflow checker that runs via
the profiling _mcount hook.  So every function call we check
if the stack is getting overused.

If so, we jump onto a special static debugging stack and print
the stack overflow message.

And yes it works with IRQ stacks which is all that sparc64 uses
nowadays.

Perhaps this is useful enough to make generic.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Paul Mundt]

On Wed, Aug 27, 2008 at 05:46:05PM -0700, David Miller wrote:
> From: Paul Mundt <lethal@linux-sh.org>
> Date: Thu, 28 Aug 2008 09:32:13 +0900
> 
> > On Wed, Aug 27, 2008 at 08:35:44PM +0300, Adrian Bunk wrote:
> > > CONFIG_DEBUG_STACKOVERFLOW should give you the same information, and if
> > > wanted with an arbitrary limit.
> >
> > In some cases, yes. In the CONFIG_DEBUG_STACKOVERFLOW case the check is
> > only performed from do_IRQ(), which is sporadic at best, especially on
> > tickless. While it catches some things, it's not a complete solution in
> > and of iteslf.
> 
> BTW, on sparc64 we have a stack overflow checker that runs via
> the profiling _mcount hook.  So every function call we check
> if the stack is getting overused.
> 
> If so, we jump onto a special static debugging stack and print
> the stack overflow message.
> 
> And yes it works with IRQ stacks which is all that sparc64 uses
> nowadays.
> 
> Perhaps this is useful enough to make generic.

Thanks for the pointer, I'll take a look at it!

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Greg Ungerer]

Paul Mundt wrote:
> On Wed, Aug 27, 2008 at 02:58:30PM +0300, Adrian Bunk wrote:
>> On Tue, Aug 26, 2008 at 05:28:37PM -0700, Linus Torvalds wrote:
>>> On Wed, 27 Aug 2008, Adrian Bunk wrote:
>>>> When did we get callpaths like like nfs+xfs+md+scsi reliably 
>>>> working with 4kB stacks on x86-32?
>>> XFS may never have been usable, but the rest, sure.
>>>
>>> And you seem to be making this whole argument an excuse to SUCK, adn an 
>>> excuse to let gcc crap even more on our stack space.
>>>
>>> Why?
>>>
>>> Why aren't you saying that we should be able to do better? Instead, you 
>>> seem to asking us to do even worse than we do now?
>> My main point is:
>> - getting 4kB stacks working reliably is a hard task
>> - having an eye on gcc increasing the stack usage, and fixing it if
>>   required, is relatively easy
>>
>> If we should be able to do better at getting (and keeping) 4kB stacks 
>> working, then coping with possible inlining problems caused by gcc
>> should not be a big problem for us.
>>
> Out of the architectures you've mentioned for 4k stacks, they also tend
> to do IRQ stacks, which is something you seem to have overlooked.
> 
> In addition to that, debugging the runaway stack users on 4k tends to be
> easier anyways since you end up blowing the stack a lot sooner. On sh
> we've had pretty good luck with it, though most of our users are using
> fairly deterministic workloads and continually profiling the footprint.
> Anything that runs away or uses an insane amount of stack space needs to
> be fixed well before that anyways, so catching it sooner is always
> preferable. I imagine the same case is true for m68knommu (even sans IRQ
> stacks).

Yep, definitely true for m68knommu in my experience. I haven't had
any problems with 4k stacks recently. But yes the workloads do tend
to be constrained - and almost never use any of the more exotic
filesystems or drivers.



> Things might be more sensitive on x86, but it's certainly not something
> that's a huge problem for the various embedded platforms to wire up,
> whether they want to go the IRQ stack route or not.
> 
> In any event, lack of support for something on embedded architectures in
> the kernel is more often due to apathy/utter indifference on the part of
> the architecture maintainer rather than being indicative of any intrinsic
> difficulty in supporting the thing in question. Most new "features" on the
> lesser maintained architectures tend to end up there either out of peer
> pressure or copying-and-pasting accidents rather than any sort of design.
> ;-)

Indeed :-)

Regards
Greg


------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
Secure Computing Corporation                PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Christoph Hellwig]

On Wed, Aug 27, 2008 at 01:40:10PM -0700, Linus Torvalds wrote:
> 
> 
> On Wed, 27 Aug 2008, Peter Osterlund wrote:
> > 
> > Why not just revert the offending change and try again during the next
> > merge window, assuming someone has figured out an acceptable way to
> > handle this mess by then?
> 
> Well,, for 2.6.27 that's what we'll have to do. But there's actually a 
> real problem here - the unlocked ioctl's (which we _should_ prefer) have a 
> strictly weaker and worse interface. I also wonder if any other 
> block_ioctl users were converted..

Actually both interfaces are a fscking disaster.  The right things to
pass is neither and inode nor a file but a struct block_device.  Al had
all this work done a while and it just needs rebasing to a current tree:

	http://git.kernel.org/?p=linux/kernel/git/viro/bdev.git;a=summary

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Adrian Bunk]

On Thu, Aug 28, 2008 at 09:32:13AM +0900, Paul Mundt wrote:
> On Wed, Aug 27, 2008 at 08:35:44PM +0300, Adrian Bunk wrote:
> > On Thu, Aug 28, 2008 at 01:00:52AM +0900, Paul Mundt wrote:
> > > On Wed, Aug 27, 2008 at 02:58:30PM +0300, Adrian Bunk wrote:
> > > In addition to that, debugging the runaway stack users on 4k tends to be
> > > easier anyways since you end up blowing the stack a lot sooner. On sh
> > > we've had pretty good luck with it, though most of our users are using
> > > fairly deterministic workloads and continually profiling the footprint.
> > > Anything that runs away or uses an insane amount of stack space needs to
> > > be fixed well before that anyways, so catching it sooner is always
> > > preferable. I imagine the same case is true for m68knommu (even sans IRQ
> > > stacks).
> > 
> > CONFIG_DEBUG_STACKOVERFLOW should give you the same information, and if
> > wanted with an arbitrary limit.
> > 
> In some cases, yes. In the CONFIG_DEBUG_STACKOVERFLOW case the check is
> only performed from do_IRQ(), which is sporadic at best, especially on
> tickless. While it catches some things, it's not a complete solution in
> and of iteslf.
> 
> In addition to this, there are even fewer platforms that support it than
> there are platforms that do 4k stacks. At first glance, it looks like
> it's only m32r, powerpc, sh, x86, and xtensa.
>...

As far as I can see the only architectures that optionally offer 4kB 
stacks today are m68knommu, s390, sh and x86.

Did I miss some architectures or is 5 < 4 ;) ?

> Others support the Kconfig
> option, but don't seem to realize that it's not an option that the kernel
> does anything with by itself, and so don't actually do anything (ie,
> FRV).

Unless I miss anything these "others" include only FRV.

> > IMHO there seems to currently be a mismatch between it's maintainance 
> > cost and the actual number of users. That's in my opinion the main 
> > problem with it, no matter in which direction it gets resolved.
> > 
> Perhaps that's true on x86, but in general I take issue with that. On sh
> we've had to do very little maintenance for it and most shipping products
> are using it today (at least on MMU-Linux, we don't bother with it on
> nommu). Most of the problems we ran in to with 4k stacks tended to be
> stuff that we wanted to fix for 8k anyways. I suspect that this case is
> true for the other embedded platforms also.
>...

Most stack issues are not platform or architecture specific.

The maintainance effort therefore mostly depends on whether a non-zero 
number of architectures uses 4kB stacks.

And if something is considered to be important for small embedded 
systems, but not supported on ARM, MIPS or PowerPC, then that's 
a bit strange.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jes Sorensen]

[-- Attachment #1: Type: text/plain, Size: 1638 bytes --]

David Miller wrote:
>>> Otherwise you have to modify cpumask_t objects and thus pluck
>>> them onto the stack where they take up silly amounts of space.
>> Yes, I had proposed either modifying, or supplementing a new
>> smp_call function to pass the cpumask_t as a pointer (similar
>> to set_cpus_allowed_ptr.)  But an ABI change such as this was
>> not well received at the time.
> 
> What it seems to come down to is that any cpumask_t not inside of
> a dynamically allocated object should be marked const.
> 
> And that is something we can enforce at compile time.
> 
> Linus has just suggested dynamically allocating cpumask_t's
> for such cases but I don't see that as the fix either.
> 
> Just mark them const and enforce that cpumask_t objects can only
> be modified when they appear in dynamically allocated objects.

Dave and others,

Sorry if I jump into the middle of the thread. Stopped subscribing to
lkml for a while, so this is through the archives.

Ran into some of these issues with KVM too, and noticed just how much
we pass cpumask_t around in the smp_call functions :-( In fact, the
only arch that did pretty well on this front was sparc64.

I totally agree, that marking them const makes a ton of sense, but at
the same time I suggest we convert smp_call_function_mask() to take a
pointer to the cpumask_t. I whipped up the following patch, which cuts
down the amont of memcpy calls emitted quite a fair bit.

I have only tested this on ia64, but it boots, so it's obviously
perfect<tm> :-)

Comments, suggestions welcome.

I have a followup patch that makes virt/kvm/kvm_main.c use the new
interface.

Cheers,
Jes


[-- Attachment #2: 0040-smp-call-cpumask.patch --]
[-- Type: text/plain, Size: 14273 bytes --]

Change smp_call_function_mask() to take a pointer to the cpumask_t
rather than passing it by value. This avoids recursive copies of the
cpumask_t on the stack in the IPI call. For large NR_CPUS, this is
particularly bad, and the cost of doing this for
NR_CPUS < bits_per_long is negligeble.

Signed-off-by: Jes Sorensen <jes@sgi.com>

---
 arch/alpha/include/asm/smp.h    |    2 +-
 arch/alpha/kernel/smp.c         |    4 ++--
 arch/arm/include/asm/smp.h      |    2 +-
 arch/arm/kernel/smp.c           |    4 ++--
 arch/ia64/include/asm/smp.h     |    2 +-
 arch/ia64/kernel/smp.c          |    6 +++---
 arch/m32r/kernel/smp.c          |    4 ++--
 arch/mips/kernel/smp.c          |    4 ++--
 arch/parisc/kernel/smp.c        |    6 +++---
 arch/powerpc/include/asm/smp.h  |    2 +-
 arch/powerpc/kernel/smp.c       |    4 ++--
 arch/sh/include/asm/smp.h       |    2 +-
 arch/sh/kernel/smp.c            |    4 ++--
 arch/sparc/include/asm/smp_64.h |    2 +-
 arch/sparc64/kernel/smp.c       |    4 ++--
 include/asm-m32r/smp.h          |    2 +-
 include/asm-mips/smp.h          |    2 +-
 include/asm-parisc/smp.h        |    2 +-
 include/asm-x86/smp.h           |    4 ++--
 include/linux/smp.h             |    2 +-
 kernel/smp.c                    |   15 ++++++++-------
 virt/kvm/kvm_main.c             |    4 ++--
 22 files changed, 42 insertions(+), 41 deletions(-)

Index: linux-2.6.git/arch/alpha/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/alpha/include/asm/smp.h
+++ linux-2.6.git/arch/alpha/include/asm/smp.h
@@ -48,7 +48,7 @@
 #define cpu_possible_map	cpu_present_map
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #else /* CONFIG_SMP */
 
Index: linux-2.6.git/arch/alpha/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/alpha/kernel/smp.c
+++ linux-2.6.git/arch/alpha/kernel/smp.c
@@ -637,9 +637,9 @@
 	send_ipi_message(to_whom, IPI_CPU_STOP);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	send_ipi_message(mask, IPI_CALL_FUNC);
+	send_ipi_message(*mask, IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
Index: linux-2.6.git/arch/arm/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/arm/include/asm/smp.h
+++ linux-2.6.git/arch/arm/include/asm/smp.h
@@ -102,7 +102,7 @@
 extern void platform_cpu_enable(unsigned int cpu);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 /*
  * Local timer interrupt handling function (can be IPI'ed).
Index: linux-2.6.git/arch/arm/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/arm/kernel/smp.c
+++ linux-2.6.git/arch/arm/kernel/smp.c
@@ -356,9 +356,9 @@
 	local_irq_restore(flags);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	send_ipi_message(mask, IPI_CALL_FUNC);
+	send_ipi_message(*mask, IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
Index: linux-2.6.git/arch/ia64/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/ia64/include/asm/smp.h
+++ linux-2.6.git/arch/ia64/include/asm/smp.h
@@ -127,7 +127,7 @@
 extern int is_multithreading_enabled(void);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #else /* CONFIG_SMP */
 
Index: linux-2.6.git/arch/ia64/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/ia64/kernel/smp.c
+++ linux-2.6.git/arch/ia64/kernel/smp.c
@@ -166,11 +166,11 @@
  * Called with preemption disabled.
  */
 static inline void
-send_IPI_mask(cpumask_t mask, int op)
+send_IPI_mask(cpumask_t *mask, int op)
 {
 	unsigned int cpu;
 
-	for_each_cpu_mask(cpu, mask) {
+	for_each_cpu_mask(cpu, *mask) {
 			send_IPI_single(cpu, op);
 	}
 }
@@ -316,7 +316,7 @@
 	send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	send_IPI_mask(mask, IPI_CALL_FUNC);
 }
Index: linux-2.6.git/arch/m32r/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/m32r/kernel/smp.c
+++ linux-2.6.git/arch/m32r/kernel/smp.c
@@ -546,9 +546,9 @@
 	for ( ; ; );
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	send_IPI_mask(mask, CALL_FUNCTION_IPI, 0);
+	send_IPI_mask(*mask, CALL_FUNCTION_IPI, 0);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
Index: linux-2.6.git/arch/mips/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/mips/kernel/smp.c
+++ linux-2.6.git/arch/mips/kernel/smp.c
@@ -131,9 +131,9 @@
 	cpu_idle();
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	mp_ops->send_ipi_mask(mask, SMP_CALL_FUNCTION);
+	mp_ops->send_ipi_mask(*mask, SMP_CALL_FUNCTION);
 }
 
 /*
Index: linux-2.6.git/arch/parisc/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/parisc/kernel/smp.c
+++ linux-2.6.git/arch/parisc/kernel/smp.c
@@ -228,11 +228,11 @@
 }
 
 static void
-send_IPI_mask(cpumask_t mask, enum ipi_message_type op)
+send_IPI_mask(cpumask_t *mask, enum ipi_message_type op)
 {
 	int cpu;
 
-	for_each_cpu_mask(cpu, mask)
+	for_each_cpu_mask(cpu, *mask)
 		ipi_send(cpu, op);
 }
 
@@ -274,7 +274,7 @@
 	send_IPI_allbutself(IPI_NOP);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	send_IPI_mask(mask, IPI_CALL_FUNC);
 }
Index: linux-2.6.git/arch/powerpc/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/powerpc/include/asm/smp.h
+++ linux-2.6.git/arch/powerpc/include/asm/smp.h
@@ -119,7 +119,7 @@
 extern struct smp_ops_t *smp_ops;
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif /* __ASSEMBLY__ */
 
Index: linux-2.6.git/arch/powerpc/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/powerpc/kernel/smp.c
+++ linux-2.6.git/arch/powerpc/kernel/smp.c
@@ -135,11 +135,11 @@
 	smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	unsigned int cpu;
 
-	for_each_cpu_mask(cpu, mask)
+	for_each_cpu_mask(cpu, *mask)
 		smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
 }
 
Index: linux-2.6.git/arch/sh/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/sh/include/asm/smp.h
+++ linux-2.6.git/arch/sh/include/asm/smp.h
@@ -39,7 +39,7 @@
 int plat_register_ipi_handler(unsigned int message,
 			      void (*handler)(void *), void *arg);
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #else
 
Index: linux-2.6.git/arch/sh/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/sh/kernel/smp.c
+++ linux-2.6.git/arch/sh/kernel/smp.c
@@ -171,11 +171,11 @@
 	smp_call_function(stop_this_cpu, 0, 0);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	int cpu;
 
-	for_each_cpu_mask(cpu, mask)
+	for_each_cpu_mask(cpu, *mask)
 		plat_send_ipi(cpu, SMP_MSG_FUNCTION);
 }
 
Index: linux-2.6.git/arch/sparc/include/asm/smp_64.h
===================================================================
--- linux-2.6.git.orig/arch/sparc/include/asm/smp_64.h
+++ linux-2.6.git/arch/sparc/include/asm/smp_64.h
@@ -35,7 +35,7 @@
 extern int sparc64_multi_core;
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 /*
  *	General functions that each host system must provide.
Index: linux-2.6.git/arch/sparc64/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/sparc64/kernel/smp.c
+++ linux-2.6.git/arch/sparc64/kernel/smp.c
@@ -810,9 +810,9 @@
 
 extern unsigned long xcall_call_function;
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	xcall_deliver((u64) &xcall_call_function, 0, 0, &mask);
+	xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
 }
 
 extern unsigned long xcall_call_function_single;
Index: linux-2.6.git/include/asm-m32r/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-m32r/smp.h
+++ linux-2.6.git/include/asm-m32r/smp.h
@@ -90,7 +90,7 @@
 extern unsigned long send_IPI_mask_phys(cpumask_t, int, int);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif	/* not __ASSEMBLY__ */
 
Index: linux-2.6.git/include/asm-mips/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-mips/smp.h
+++ linux-2.6.git/include/asm-mips/smp.h
@@ -58,6 +58,6 @@
 extern asmlinkage void smp_call_function_interrupt(void);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif /* __ASM_SMP_H */
Index: linux-2.6.git/include/asm-parisc/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-parisc/smp.h
+++ linux-2.6.git/include/asm-parisc/smp.h
@@ -31,7 +31,7 @@
 extern void smp_send_all_nop(void);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif /* !ASSEMBLY */
 
Index: linux-2.6.git/include/asm-x86/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-x86/smp.h
+++ linux-2.6.git/include/asm-x86/smp.h
@@ -101,9 +101,9 @@
 	smp_ops.send_call_func_single_ipi(cpu);
 }
 
-static inline void arch_send_call_function_ipi(cpumask_t mask)
+static inline void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	smp_ops.send_call_func_ipi(mask);
+	smp_ops.send_call_func_ipi(*mask);
 }
 
 void native_smp_prepare_boot_cpu(void);
Index: linux-2.6.git/include/linux/smp.h
===================================================================
--- linux-2.6.git.orig/include/linux/smp.h
+++ linux-2.6.git/include/linux/smp.h
@@ -62,7 +62,7 @@
  * Call a function on all other processors
  */
 int smp_call_function(void(*func)(void *info), void *info, int wait);
-int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
+int smp_call_function_mask(cpumask_t *mask, void(*func)(void *info), void *info,
 				int wait);
 int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
 				int wait);
Index: linux-2.6.git/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/kernel/smp.c
+++ linux-2.6.git/kernel/smp.c
@@ -318,7 +318,7 @@
  * hardware interrupt handler or from a bottom half handler. Preemption
  * must be disabled when calling this function.
  */
-int smp_call_function_mask(cpumask_t mask, void (*func)(void *), void *info,
+int smp_call_function_mask(cpumask_t *mask, void (*func)(void *), void *info,
 			   int wait)
 {
 	struct call_function_data d;
@@ -334,8 +334,8 @@
 	cpu = smp_processor_id();
 	allbutself = cpu_online_map;
 	cpu_clear(cpu, allbutself);
-	cpus_and(mask, mask, allbutself);
-	num_cpus = cpus_weight(mask);
+	cpus_and(*mask, *mask, allbutself);
+	num_cpus = cpus_weight(*mask);
 
 	/*
 	 * If zero CPUs, return. If just a single CPU, turn this request
@@ -344,7 +344,7 @@
 	if (!num_cpus)
 		return 0;
 	else if (num_cpus == 1) {
-		cpu = first_cpu(mask);
+		cpu = first_cpu(*mask);
 		return smp_call_function_single(cpu, func, info, wait);
 	}
 
@@ -364,7 +364,7 @@
 	data->csd.func = func;
 	data->csd.info = info;
 	data->refs = num_cpus;
-	data->cpumask = mask;
+	data->cpumask = *mask;
 
 	spin_lock_irqsave(&call_function_lock, flags);
 	list_add_tail_rcu(&data->csd.list, &call_function_queue);
@@ -377,7 +377,7 @@
 	if (wait) {
 		csd_flag_wait(&data->csd);
 		if (unlikely(slowpath))
-			smp_call_function_mask_quiesce_stack(mask);
+			smp_call_function_mask_quiesce_stack(*mask);
 	}
 
 	return 0;
@@ -402,9 +402,10 @@
 int smp_call_function(void (*func)(void *), void *info, int wait)
 {
 	int ret;
+	cpumask_t tmp_online_map = cpu_online_map;
 
 	preempt_disable();
-	ret = smp_call_function_mask(cpu_online_map, func, info, wait);
+	ret = smp_call_function_mask(&tmp_online_map, func, info, wait);
 	preempt_enable();
 	return ret;
 }
Index: linux-2.6.git/virt/kvm/kvm_main.c
===================================================================
--- linux-2.6.git.orig/virt/kvm/kvm_main.c
+++ linux-2.6.git/virt/kvm/kvm_main.c
@@ -124,7 +124,7 @@
 	if (cpus_empty(cpus))
 		goto out;
 	++kvm->stat.remote_tlb_flush;
-	smp_call_function_mask(cpus, ack_flush, NULL, 1);
+	smp_call_function_mask(&cpus, ack_flush, NULL, 1);
 out:
 	put_cpu();
 }
@@ -149,7 +149,7 @@
 	}
 	if (cpus_empty(cpus))
 		goto out;
-	smp_call_function_mask(cpus, ack_flush, NULL, 1);
+	smp_call_function_mask(&cpus, ack_flush, NULL, 1);
 out:
 	put_cpu();
 }

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Fri, 29 Aug 2008, Jes Sorensen wrote:
> 
> I have only tested this on ia64, but it boots, so it's obviously
> perfect<tm> :-)

Well, it probably boots because it doesn't really seem to _change_ much of 
anything.

Things like this:

	-static inline void arch_send_call_function_ipi(cpumask_t mask)
	+static inline void arch_send_call_function_ipi(cpumask_t *mask)
	 {
	-       smp_ops.send_call_func_ipi(mask);
	+       smp_ops.send_call_func_ipi(*mask);
	 }

will still do that stack allocation at the time of the call. You'd have to 
pass the thing all the way down as a pointer..

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[David Miller]

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 29 Aug 2008 09:14:44 -0700 (PDT)

> Well, it probably boots because it doesn't really seem to _change_ much of 
> anything.
> 
> Things like this:
> 
> 	-static inline void arch_send_call_function_ipi(cpumask_t mask)
> 	+static inline void arch_send_call_function_ipi(cpumask_t *mask)
> 	 {
> 	-       smp_ops.send_call_func_ipi(mask);
> 	+       smp_ops.send_call_func_ipi(*mask);
> 	 }
> 
> will still do that stack allocation at the time of the call. You'd have to 
> pass the thing all the way down as a pointer..

True, but we have to get there one step at a time.

BTW, sparc64 already wants a pointer here, so it's completely ready for
this:

void arch_send_call_function_ipi(cpumask_t mask)
{
	xcall_deliver((u64) &xcall_call_function, 0, 0, &mask);
}

Re: [Bug #11355] Regression in 2.6.27-rc2 when cross-building the kernel

[David Woodhouse]

On Sun, 2008-08-24 at 23:34 +0200, Rafael J. Wysocki wrote:
> On Saturday, 23 of August 2008, Rafael J. Wysocki wrote:
> > This message has been generated automatically as a part of a report
> > of recent regressions.
> > 
> > The following bug entry is on the current list of known regressions
> > from 2.6.26.  Please verify if it still should be listed and let me know
> > (either way).
> > 
> > 
> > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11355
> > Subject		: Regression in 2.6.27-rc2 when cross-building the kernel
> > Submitter	: Larry Finger <Larry.Finger@lwfinger.net>
> > Date		: 2008-08-16 2:38 (8 days old)
> > References	: http://marc.info/?l=linux-kernel&m=121885432118368&w=4
> 
> As I wrote in the Bugzilla, I'm seeing a related problem.
> 
> Namely, I build kernels on one box, with 'make O=<target>', then I mount
> <target> on another one over NFS, 'cd' to it and try to install the kernel
> modules with 'make modules_install'.  This results in 'HOSTCC firmware/ihex2fw'
> and 'fatal error: ...: Read-only file system'.  It's readily reproducible.
> 
> Commenting out line 1130 of Makefile
> ("$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst")
> obviously helps, so it looks like Makefile.fwinst needs fixing.

I don't like this much, but it should do the trick... please confirm.

diff --git a/firmware/Makefile b/firmware/Makefile
index aab12bf..e7130b5 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -166,15 +166,28 @@ $(patsubst %,$(obj)/%.gen.o, $(fw-external-y)): $(obj)/%.gen.o: $(fwdir)/%
 $(obj)/%: $(obj)/%.ihex | $(objtree)/$(obj)/$$(dir %)
 	$(call cmd,ihex)
 
+# Don't depend on ihex2fw if we're installing and it already exists.
+# Putting it after | in the dependencies doesn't seem sufficient when
+# we're installing after a cross-compile, because ihex2fw has dependencies
+# on stuff like /usr/lib/gcc/ppc64-redhat-linux/4.3.0/include/stddef.h and 
+# thus wants to be rebuilt. Which it can't be, if the prebuilt kernel tree
+# is exported read-only for someone to run 'make install'.
+ifeq ($(INSTALL):$(wildcard $(obj)/ihex2fw),install:$(obj)/ihex2fw)
+ihex2fw_dep :=
+else
+ihex2fw_dep := $(obj)/ihex2fw
+endif
+
+
 # .HEX is also Intel HEX, but where the offset and length in each record
 # is actually meaningful, because the firmware has to be loaded in a certain
 # order rather than as a single binary blob. Thus, we convert them into our
 # more compact binary representation of ihex records (<linux/ihex.h>)
-$(obj)/%.fw: $(obj)/%.HEX $(obj)/ihex2fw | $(objtree)/$(obj)/$$(dir %)
+$(obj)/%.fw: $(obj)/%.HEX $(ihex2fw_dep) | $(objtree)/$(obj)/$$(dir %)
 	$(call cmd,ihex2fw)
 
 # .H16 is our own modified form of Intel HEX, with 16-bit length for records.
-$(obj)/%.fw: $(obj)/%.H16 $(obj)/ihex2fw | $(objtree)/$(obj)/$$(dir %)
+$(obj)/%.fw: $(obj)/%.H16 $(ihex2fw_dep) | $(objtree)/$(obj)/$$(dir %)
 	$(call cmd,h16tofw)
 
 $(firmware-dirs):

-- 
dwmw2

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jes Sorensen]

Linus Torvalds wrote:
> 
> On Fri, 29 Aug 2008, Jes Sorensen wrote:
>> I have only tested this on ia64, but it boots, so it's obviously
>> perfect<tm> :-)
> 
> Well, it probably boots because it doesn't really seem to _change_ much of 
> anything.

Hi Linus,

I realize that, but as I have been doing this work on ia64, I didn't
want to mess too much with the x86 code. The ia64 part of the patch does
change things :-)

If someone with more x86 knowledge would want to try and make that part
of the patch better, and more importantly test it, I'd be quite keen on
helping out.

Cheers,
Jes


> Things like this:
> 
> 	-static inline void arch_send_call_function_ipi(cpumask_t mask)
> 	+static inline void arch_send_call_function_ipi(cpumask_t *mask)
> 	 {
> 	-       smp_ops.send_call_func_ipi(mask);
> 	+       smp_ops.send_call_func_ipi(*mask);
> 	 }
> 
> will still do that stack allocation at the time of the call. You'd have to 
> pass the thing all the way down as a pointer..
> 
> 			Linus
> 

Re: [Bug #11355] Regression in 2.6.27-rc2 when cross-building the kernel

[Larry Finger]

David Woodhouse wrote:
> On Sun, 2008-08-24 at 23:34 +0200, Rafael J. Wysocki wrote:
>> On Saturday, 23 of August 2008, Rafael J. Wysocki wrote:
>>> This message has been generated automatically as a part of a report
>>> of recent regressions.
>>>
>>> The following bug entry is on the current list of known regressions
>>> from 2.6.26.  Please verify if it still should be listed and let me know
>>> (either way).
>>>
>>>
>>> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11355
>>> Subject		: Regression in 2.6.27-rc2 when cross-building the kernel
>>> Submitter	: Larry Finger <Larry.Finger@lwfinger.net>
>>> Date		: 2008-08-16 2:38 (8 days old)
>>> References	: http://marc.info/?l=linux-kernel&m=121885432118368&w=4
>> As I wrote in the Bugzilla, I'm seeing a related problem.
>>
>> Namely, I build kernels on one box, with 'make O=<target>', then I mount
>> <target> on another one over NFS, 'cd' to it and try to install the kernel
>> modules with 'make modules_install'.  This results in 'HOSTCC firmware/ihex2fw'
>> and 'fatal error: ...: Read-only file system'.  It's readily reproducible.
>>
>> Commenting out line 1130 of Makefile
>> ("$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst")
>> obviously helps, so it looks like Makefile.fwinst needs fixing.
> 
> I don't like this much, but it should do the trick... please confirm.

Yes, the patch fixes the problem. Thanks.

Larry

Re: [Bug #11355] Regression in 2.6.27-rc2 when cross-building the kernel

[David Woodhouse]

On Mon, 2008-09-01 at 11:51 -0500, Larry Finger wrote:
> David Woodhouse wrote:
> > On Sun, 2008-08-24 at 23:34 +0200, Rafael J. Wysocki wrote:
> >> On Saturday, 23 of August 2008, Rafael J. Wysocki wrote:
> >>> This message has been generated automatically as a part of a report
> >>> of recent regressions.
> >>>
> >>> The following bug entry is on the current list of known regressions
> >>> from 2.6.26.  Please verify if it still should be listed and let me know
> >>> (either way).
> >>>
> >>>
> >>> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11355
> >>> Subject		: Regression in 2.6.27-rc2 when cross-building the kernel
> >>> Submitter	: Larry Finger <Larry.Finger@lwfinger.net>
> >>> Date		: 2008-08-16 2:38 (8 days old)
> >>> References	: http://marc.info/?l=linux-kernel&m=121885432118368&w=4
> >> As I wrote in the Bugzilla, I'm seeing a related problem.
> >>
> >> Namely, I build kernels on one box, with 'make O=<target>', then I mount
> >> <target> on another one over NFS, 'cd' to it and try to install the kernel
> >> modules with 'make modules_install'.  This results in 'HOSTCC firmware/ihex2fw'
> >> and 'fatal error: ...: Read-only file system'.  It's readily reproducible.
> >>
> >> Commenting out line 1130 of Makefile
> >> ("$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.fwinst obj=firmware __fw_modinst")
> >> obviously helps, so it looks like Makefile.fwinst needs fixing.
> > 
> > I don't like this much, but it should do the trick... please confirm.
> 
> Yes, the patch fixes the problem. Thanks.

Ok, I have a small handful of fixes to send to Linus for 2.6.27; Unless
Sam (or someone else) comes up with a better answer, I'll make sure that
goes with them.

Thanks.

-- 
dwmw2

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Jens Axboe]

On Thu, Aug 28 2008, Christoph Hellwig wrote:
> On Wed, Aug 27, 2008 at 01:40:10PM -0700, Linus Torvalds wrote:
> > 
> > 
> > On Wed, 27 Aug 2008, Peter Osterlund wrote:
> > > 
> > > Why not just revert the offending change and try again during the next
> > > merge window, assuming someone has figured out an acceptable way to
> > > handle this mess by then?
> > 
> > Well,, for 2.6.27 that's what we'll have to do. But there's actually a 
> > real problem here - the unlocked ioctl's (which we _should_ prefer) have a 
> > strictly weaker and worse interface. I also wonder if any other 
> > block_ioctl users were converted..
> 
> Actually both interfaces are a fscking disaster.  The right things to
> pass is neither and inode nor a file but a struct block_device.  Al had
> all this work done a while and it just needs rebasing to a current tree:
> 
> 	http://git.kernel.org/?p=linux/kernel/git/viro/bdev.git;a=summary

Completely agreed. Al, I remember talking to you about this at the
storage summit back in february. What are your current plans wrt moving
this forward?

-- 
Jens Axboe

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Jes Sorensen]

[-- Attachment #1: Type: text/plain, Size: 834 bytes --]

Linus Torvalds wrote:
> 
> On Fri, 29 Aug 2008, Jes Sorensen wrote:
>> I have only tested this on ia64, but it boots, so it's obviously
>> perfect<tm> :-)
> 
> Well, it probably boots because it doesn't really seem to _change_ much of 
> anything.
> 
> Things like this:
> 
> 	-static inline void arch_send_call_function_ipi(cpumask_t mask)
> 	+static inline void arch_send_call_function_ipi(cpumask_t *mask)
> 	 {
> 	-       smp_ops.send_call_func_ipi(mask);
> 	+       smp_ops.send_call_func_ipi(*mask);
> 	 }
> 
> will still do that stack allocation at the time of the call. You'd have to 
> pass the thing all the way down as a pointer..

Linus,

Ok, so here's a version which tries to do the right thing on x86 as
well. Build tested on x86_64, but don't have an easy way to test it
right now. It's booting on ia64.

Cheers,
Jes


[-- Attachment #2: 0040-smp-call-cpumask.patch --]
[-- Type: text/plain, Size: 26200 bytes --]

Change smp_call_function_mask() to take a pointer to the cpumask_t
rather than passing it by value. This avoids recursive copies of the
cpumask_t on the stack in the IPI call. For large NR_CPUS, this is
particularly bad, and the cost of doing this for
NR_CPUS < bits_per_long is negligeble.

Signed-off-by: Jes Sorensen <jes@sgi.com>

---
 arch/alpha/include/asm/smp.h            |    2 +-
 arch/alpha/kernel/smp.c                 |    4 ++--
 arch/arm/include/asm/smp.h              |    2 +-
 arch/arm/kernel/smp.c                   |    4 ++--
 arch/ia64/include/asm/smp.h             |    2 +-
 arch/ia64/kernel/smp.c                  |    6 +++---
 arch/m32r/kernel/smp.c                  |    4 ++--
 arch/mips/kernel/smp.c                  |    4 ++--
 arch/parisc/kernel/smp.c                |    6 +++---
 arch/powerpc/include/asm/smp.h          |    2 +-
 arch/powerpc/kernel/smp.c               |    4 ++--
 arch/sh/include/asm/smp.h               |    2 +-
 arch/sh/kernel/smp.c                    |    4 ++--
 arch/sparc/include/asm/smp_64.h         |    2 +-
 arch/sparc64/kernel/smp.c               |    4 ++--
 arch/x86/kernel/apic_32.c               |    2 +-
 arch/x86/kernel/apic_64.c               |    2 +-
 arch/x86/kernel/crash.c                 |    2 +-
 arch/x86/kernel/genapic_flat_64.c       |   20 ++++++++++++--------
 arch/x86/kernel/genx2apic_uv_x.c        |   10 ++++++----
 arch/x86/kernel/io_apic_64.c            |    6 ++++--
 arch/x86/kernel/smp.c                   |   12 ++++++++----
 arch/x86/kernel/tlb_32.c                |    2 +-
 arch/x86/kernel/tlb_64.c                |    2 +-
 arch/x86/xen/smp.c                      |   13 +++++++------
 include/asm-m32r/smp.h                  |    2 +-
 include/asm-mips/smp.h                  |    2 +-
 include/asm-parisc/smp.h                |    2 +-
 include/asm-x86/genapic_32.h            |    2 +-
 include/asm-x86/genapic_64.h            |    2 +-
 include/asm-x86/mach-default/mach_ipi.h |   10 ++++++----
 include/asm-x86/smp.h                   |    6 +++---
 include/linux/smp.h                     |    2 +-
 kernel/smp.c                            |   15 ++++++++-------
 virt/kvm/kvm_main.c                     |    4 ++--
 35 files changed, 93 insertions(+), 77 deletions(-)

Index: linux-2.6.git/arch/alpha/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/alpha/include/asm/smp.h
+++ linux-2.6.git/arch/alpha/include/asm/smp.h
@@ -48,7 +48,7 @@
 #define cpu_possible_map	cpu_present_map
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #else /* CONFIG_SMP */
 
Index: linux-2.6.git/arch/alpha/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/alpha/kernel/smp.c
+++ linux-2.6.git/arch/alpha/kernel/smp.c
@@ -637,9 +637,9 @@
 	send_ipi_message(to_whom, IPI_CPU_STOP);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	send_ipi_message(mask, IPI_CALL_FUNC);
+	send_ipi_message(*mask, IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
Index: linux-2.6.git/arch/arm/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/arm/include/asm/smp.h
+++ linux-2.6.git/arch/arm/include/asm/smp.h
@@ -102,7 +102,7 @@
 extern void platform_cpu_enable(unsigned int cpu);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 /*
  * Local timer interrupt handling function (can be IPI'ed).
Index: linux-2.6.git/arch/arm/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/arm/kernel/smp.c
+++ linux-2.6.git/arch/arm/kernel/smp.c
@@ -356,9 +356,9 @@
 	local_irq_restore(flags);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	send_ipi_message(mask, IPI_CALL_FUNC);
+	send_ipi_message(*mask, IPI_CALL_FUNC);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
Index: linux-2.6.git/arch/ia64/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/ia64/include/asm/smp.h
+++ linux-2.6.git/arch/ia64/include/asm/smp.h
@@ -127,7 +127,7 @@
 extern int is_multithreading_enabled(void);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #else /* CONFIG_SMP */
 
Index: linux-2.6.git/arch/ia64/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/ia64/kernel/smp.c
+++ linux-2.6.git/arch/ia64/kernel/smp.c
@@ -166,11 +166,11 @@
  * Called with preemption disabled.
  */
 static inline void
-send_IPI_mask(cpumask_t mask, int op)
+send_IPI_mask(cpumask_t *mask, int op)
 {
 	unsigned int cpu;
 
-	for_each_cpu_mask(cpu, mask) {
+	for_each_cpu_mask(cpu, *mask) {
 			send_IPI_single(cpu, op);
 	}
 }
@@ -316,7 +316,7 @@
 	send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	send_IPI_mask(mask, IPI_CALL_FUNC);
 }
Index: linux-2.6.git/arch/m32r/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/m32r/kernel/smp.c
+++ linux-2.6.git/arch/m32r/kernel/smp.c
@@ -546,9 +546,9 @@
 	for ( ; ; );
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	send_IPI_mask(mask, CALL_FUNCTION_IPI, 0);
+	send_IPI_mask(*mask, CALL_FUNCTION_IPI, 0);
 }
 
 void arch_send_call_function_single_ipi(int cpu)
Index: linux-2.6.git/arch/mips/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/mips/kernel/smp.c
+++ linux-2.6.git/arch/mips/kernel/smp.c
@@ -131,9 +131,9 @@
 	cpu_idle();
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	mp_ops->send_ipi_mask(mask, SMP_CALL_FUNCTION);
+	mp_ops->send_ipi_mask(*mask, SMP_CALL_FUNCTION);
 }
 
 /*
Index: linux-2.6.git/arch/parisc/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/parisc/kernel/smp.c
+++ linux-2.6.git/arch/parisc/kernel/smp.c
@@ -228,11 +228,11 @@
 }
 
 static void
-send_IPI_mask(cpumask_t mask, enum ipi_message_type op)
+send_IPI_mask(cpumask_t *mask, enum ipi_message_type op)
 {
 	int cpu;
 
-	for_each_cpu_mask(cpu, mask)
+	for_each_cpu_mask(cpu, *mask)
 		ipi_send(cpu, op);
 }
 
@@ -274,7 +274,7 @@
 	send_IPI_allbutself(IPI_NOP);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	send_IPI_mask(mask, IPI_CALL_FUNC);
 }
Index: linux-2.6.git/arch/powerpc/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/powerpc/include/asm/smp.h
+++ linux-2.6.git/arch/powerpc/include/asm/smp.h
@@ -119,7 +119,7 @@
 extern struct smp_ops_t *smp_ops;
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif /* __ASSEMBLY__ */
 
Index: linux-2.6.git/arch/powerpc/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/powerpc/kernel/smp.c
+++ linux-2.6.git/arch/powerpc/kernel/smp.c
@@ -135,11 +135,11 @@
 	smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	unsigned int cpu;
 
-	for_each_cpu_mask(cpu, mask)
+	for_each_cpu_mask(cpu, *mask)
 		smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
 }
 
Index: linux-2.6.git/arch/sh/include/asm/smp.h
===================================================================
--- linux-2.6.git.orig/arch/sh/include/asm/smp.h
+++ linux-2.6.git/arch/sh/include/asm/smp.h
@@ -39,7 +39,7 @@
 int plat_register_ipi_handler(unsigned int message,
 			      void (*handler)(void *), void *arg);
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #else
 
Index: linux-2.6.git/arch/sh/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/sh/kernel/smp.c
+++ linux-2.6.git/arch/sh/kernel/smp.c
@@ -171,11 +171,11 @@
 	smp_call_function(stop_this_cpu, 0, 0);
 }
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	int cpu;
 
-	for_each_cpu_mask(cpu, mask)
+	for_each_cpu_mask(cpu, *mask)
 		plat_send_ipi(cpu, SMP_MSG_FUNCTION);
 }
 
Index: linux-2.6.git/arch/sparc/include/asm/smp_64.h
===================================================================
--- linux-2.6.git.orig/arch/sparc/include/asm/smp_64.h
+++ linux-2.6.git/arch/sparc/include/asm/smp_64.h
@@ -35,7 +35,7 @@
 extern int sparc64_multi_core;
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 /*
  *	General functions that each host system must provide.
Index: linux-2.6.git/arch/sparc64/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/sparc64/kernel/smp.c
+++ linux-2.6.git/arch/sparc64/kernel/smp.c
@@ -810,9 +810,9 @@
 
 extern unsigned long xcall_call_function;
 
-void arch_send_call_function_ipi(cpumask_t mask)
+void arch_send_call_function_ipi(cpumask_t *mask)
 {
-	xcall_deliver((u64) &xcall_call_function, 0, 0, &mask);
+	xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
 }
 
 extern unsigned long xcall_call_function_single;
Index: linux-2.6.git/arch/x86/kernel/apic_32.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/apic_32.c
+++ linux-2.6.git/arch/x86/kernel/apic_32.c
@@ -291,7 +291,7 @@
 static void lapic_timer_broadcast(cpumask_t mask)
 {
 #ifdef CONFIG_SMP
-	send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
+	send_IPI_mask(&mask, LOCAL_TIMER_VECTOR);
 #endif
 }
 
Index: linux-2.6.git/arch/x86/kernel/apic_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/apic_64.c
+++ linux-2.6.git/arch/x86/kernel/apic_64.c
@@ -280,7 +280,7 @@
 static void lapic_timer_broadcast(cpumask_t mask)
 {
 #ifdef CONFIG_SMP
-	send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
+	send_IPI_mask(&mask, LOCAL_TIMER_VECTOR);
 #endif
 }
 
Index: linux-2.6.git/arch/x86/kernel/crash.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/crash.c
+++ linux-2.6.git/arch/x86/kernel/crash.c
@@ -80,7 +80,7 @@
 	cpumask_t mask = cpu_online_map;
 	cpu_clear(safe_smp_processor_id(), mask);
 	if (!cpus_empty(mask))
-		send_IPI_mask(mask, NMI_VECTOR);
+		send_IPI_mask(&mask, NMI_VECTOR);
 }
 
 static struct notifier_block crash_nmi_nb = {
Index: linux-2.6.git/arch/x86/kernel/genapic_flat_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/genapic_flat_64.c
+++ linux-2.6.git/arch/x86/kernel/genapic_flat_64.c
@@ -58,9 +58,9 @@
 	apic_write(APIC_LDR, val);
 }
 
-static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
+static void flat_send_IPI_mask(cpumask_t *cpumask, int vector)
 {
-	unsigned long mask = cpus_addr(cpumask)[0];
+	unsigned long mask = cpus_addr(*cpumask)[0];
 	unsigned long flags;
 
 	local_irq_save(flags);
@@ -81,7 +81,7 @@
 		cpu_clear(smp_processor_id(), allbutme);
 
 		if (!cpus_empty(allbutme))
-			flat_send_IPI_mask(allbutme, vector);
+			flat_send_IPI_mask(&allbutme, vector);
 	} else if (num_online_cpus() > 1) {
 		__send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL);
 	}
@@ -89,8 +89,10 @@
 
 static void flat_send_IPI_all(int vector)
 {
+	cpumask_t tmp_online_map = cpu_online_map;
+
 	if (vector == NMI_VECTOR)
-		flat_send_IPI_mask(cpu_online_map, vector);
+		flat_send_IPI_mask(&tmp_online_map, vector);
 	else
 		__send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
 }
@@ -141,9 +143,9 @@
 	return cpumask_of_cpu(cpu);
 }
 
-static void physflat_send_IPI_mask(cpumask_t cpumask, int vector)
+static void physflat_send_IPI_mask(cpumask_t *cpumask, int vector)
 {
-	send_IPI_mask_sequence(cpumask, vector);
+	send_IPI_mask_sequence(*cpumask, vector);
 }
 
 static void physflat_send_IPI_allbutself(int vector)
@@ -151,12 +153,14 @@
 	cpumask_t allbutme = cpu_online_map;
 
 	cpu_clear(smp_processor_id(), allbutme);
-	physflat_send_IPI_mask(allbutme, vector);
+	physflat_send_IPI_mask(&allbutme, vector);
 }
 
 static void physflat_send_IPI_all(int vector)
 {
-	physflat_send_IPI_mask(cpu_online_map, vector);
+	cpumask_t tmp_online_map = cpu_online_map;
+
+	physflat_send_IPI_mask(&tmp_online_map, vector);
 }
 
 static unsigned int physflat_cpu_mask_to_apicid(cpumask_t cpumask)
Index: linux-2.6.git/arch/x86/kernel/genx2apic_uv_x.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/genx2apic_uv_x.c
+++ linux-2.6.git/arch/x86/kernel/genx2apic_uv_x.c
@@ -94,12 +94,12 @@
 	uv_write_global_mmr64(pnode, UVH_IPI_INT, val);
 }
 
-static void uv_send_IPI_mask(cpumask_t mask, int vector)
+static void uv_send_IPI_mask(cpumask_t *mask, int vector)
 {
 	unsigned int cpu;
 
 	for_each_possible_cpu(cpu)
-		if (cpu_isset(cpu, mask))
+		if (cpu_isset(cpu, *mask))
 			uv_send_IPI_one(cpu, vector);
 }
 
@@ -110,12 +110,14 @@
 	cpu_clear(smp_processor_id(), mask);
 
 	if (!cpus_empty(mask))
-		uv_send_IPI_mask(mask, vector);
+		uv_send_IPI_mask(&mask, vector);
 }
 
 static void uv_send_IPI_all(int vector)
 {
-	uv_send_IPI_mask(cpu_online_map, vector);
+	cpumask_t mask = cpu_online_map;
+
+	uv_send_IPI_mask(&mask, vector);
 }
 
 static int uv_apic_id_registered(void)
Index: linux-2.6.git/arch/x86/kernel/io_apic_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/io_apic_64.c
+++ linux-2.6.git/arch/x86/kernel/io_apic_64.c
@@ -1379,9 +1379,11 @@
 {
 	struct irq_cfg *cfg = &irq_cfg[irq];
 	unsigned long flags;
+	cpumask_t mask;
 
 	spin_lock_irqsave(&vector_lock, flags);
-	send_IPI_mask(cpumask_of_cpu(first_cpu(cfg->domain)), cfg->vector);
+	mask = cpumask_of_cpu(first_cpu(cfg->domain));
+	send_IPI_mask(&mask, cfg->vector);
 	spin_unlock_irqrestore(&vector_lock, flags);
 
 	return 1;
@@ -1446,7 +1448,7 @@
 
 		cpus_and(cleanup_mask, cfg->old_domain, cpu_online_map);
 		cfg->move_cleanup_count = cpus_weight(cleanup_mask);
-		send_IPI_mask(cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
+		send_IPI_mask(&cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
 		cfg->move_in_progress = 0;
 	}
 }
Index: linux-2.6.git/arch/x86/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/smp.c
+++ linux-2.6.git/arch/x86/kernel/smp.c
@@ -114,26 +114,30 @@
  */
 static void native_smp_send_reschedule(int cpu)
 {
+	cpumask_t mask;
+
 	if (unlikely(cpu_is_offline(cpu))) {
 		WARN_ON(1);
 		return;
 	}
-	send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR);
+	mask = cpumask_of_cpu(cpu);
+	send_IPI_mask(&mask, RESCHEDULE_VECTOR);
 }
 
 void native_send_call_func_single_ipi(int cpu)
 {
-	send_IPI_mask(cpumask_of_cpu(cpu), CALL_FUNCTION_SINGLE_VECTOR);
+	cpumask_t mask = cpumask_of_cpu(cpu);
+	send_IPI_mask(&mask, CALL_FUNCTION_SINGLE_VECTOR);
 }
 
-void native_send_call_func_ipi(cpumask_t mask)
+void native_send_call_func_ipi(cpumask_t *mask)
 {
 	cpumask_t allbutself;
 
 	allbutself = cpu_online_map;
 	cpu_clear(smp_processor_id(), allbutself);
 
-	if (cpus_equal(mask, allbutself) &&
+	if (cpus_equal(*mask, allbutself) &&
 	    cpus_equal(cpu_online_map, cpu_callout_map))
 		send_IPI_allbutself(CALL_FUNCTION_VECTOR);
 	else
Index: linux-2.6.git/arch/x86/kernel/tlb_32.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/tlb_32.c
+++ linux-2.6.git/arch/x86/kernel/tlb_32.c
@@ -158,7 +158,7 @@
 	 * We have to send the IPI only to
 	 * CPUs affected.
 	 */
-	send_IPI_mask(cpumask, INVALIDATE_TLB_VECTOR);
+	send_IPI_mask(&cpumask, INVALIDATE_TLB_VECTOR);
 
 	while (!cpus_empty(flush_cpumask))
 		/* nothing. lockup detection does not belong here */
Index: linux-2.6.git/arch/x86/kernel/tlb_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/tlb_64.c
+++ linux-2.6.git/arch/x86/kernel/tlb_64.c
@@ -186,7 +186,7 @@
 	 * We have to send the IPI only to
 	 * CPUs affected.
 	 */
-	send_IPI_mask(cpumask, INVALIDATE_TLB_VECTOR_START + sender);
+	send_IPI_mask(&cpumask, INVALIDATE_TLB_VECTOR_START + sender);
 
 	while (!cpus_empty(f->flush_cpumask))
 		cpu_relax();
Index: linux-2.6.git/arch/x86/xen/smp.c
===================================================================
--- linux-2.6.git.orig/arch/x86/xen/smp.c
+++ linux-2.6.git/arch/x86/xen/smp.c
@@ -361,24 +361,25 @@
 	xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
 }
 
-static void xen_send_IPI_mask(cpumask_t mask, enum ipi_vector vector)
+static void xen_send_IPI_mask(cpumask_t *mask, enum ipi_vector vector)
 {
 	unsigned cpu;
+	cpumask_t newmask;
 
-	cpus_and(mask, mask, cpu_online_map);
+	cpus_and(newmask, *mask, cpu_online_map);
 
-	for_each_cpu_mask_nr(cpu, mask)
+	for_each_cpu_mask_nr(cpu, newmask)
 		xen_send_IPI_one(cpu, vector);
 }
 
-static void xen_smp_send_call_function_ipi(cpumask_t mask)
+static void xen_smp_send_call_function_ipi(cpumask_t *mask)
 {
 	int cpu;
 
 	xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
 
 	/* Make sure other vcpus get a chance to run if they need to. */
-	for_each_cpu_mask_nr(cpu, mask) {
+	for_each_cpu_mask_nr(cpu, *mask) {
 		if (xen_vcpu_stolen(cpu)) {
 			HYPERVISOR_sched_op(SCHEDOP_yield, 0);
 			break;
@@ -388,7 +389,7 @@
 
 static void xen_smp_send_call_function_single_ipi(int cpu)
 {
-	xen_send_IPI_mask(cpumask_of_cpu(cpu), XEN_CALL_FUNCTION_SINGLE_VECTOR);
+	xen_send_IPI_mask(&cpumask_of_cpu(cpu), XEN_CALL_FUNCTION_SINGLE_VECTOR);
 }
 
 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
Index: linux-2.6.git/include/asm-m32r/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-m32r/smp.h
+++ linux-2.6.git/include/asm-m32r/smp.h
@@ -90,7 +90,7 @@
 extern unsigned long send_IPI_mask_phys(cpumask_t, int, int);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif	/* not __ASSEMBLY__ */
 
Index: linux-2.6.git/include/asm-mips/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-mips/smp.h
+++ linux-2.6.git/include/asm-mips/smp.h
@@ -58,6 +58,6 @@
 extern asmlinkage void smp_call_function_interrupt(void);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif /* __ASM_SMP_H */
Index: linux-2.6.git/include/asm-parisc/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-parisc/smp.h
+++ linux-2.6.git/include/asm-parisc/smp.h
@@ -31,7 +31,7 @@
 extern void smp_send_all_nop(void);
 
 extern void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi(cpumask_t mask);
+extern void arch_send_call_function_ipi(cpumask_t *mask);
 
 #endif /* !ASSEMBLY */
 
Index: linux-2.6.git/include/asm-x86/genapic_32.h
===================================================================
--- linux-2.6.git.orig/include/asm-x86/genapic_32.h
+++ linux-2.6.git/include/asm-x86/genapic_32.h
@@ -60,7 +60,7 @@
 
 #ifdef CONFIG_SMP
 	/* ipi */
-	void (*send_IPI_mask)(cpumask_t mask, int vector);
+	void (*send_IPI_mask)(cpumask_t *mask, int vector);
 	void (*send_IPI_allbutself)(int vector);
 	void (*send_IPI_all)(int vector);
 #endif
Index: linux-2.6.git/include/asm-x86/genapic_64.h
===================================================================
--- linux-2.6.git.orig/include/asm-x86/genapic_64.h
+++ linux-2.6.git/include/asm-x86/genapic_64.h
@@ -21,7 +21,7 @@
 	cpumask_t (*vector_allocation_domain)(int cpu);
 	void (*init_apic_ldr)(void);
 	/* ipi */
-	void (*send_IPI_mask)(cpumask_t mask, int vector);
+	void (*send_IPI_mask)(cpumask_t *mask, int vector);
 	void (*send_IPI_allbutself)(int vector);
 	void (*send_IPI_all)(int vector);
 	/* */
Index: linux-2.6.git/include/asm-x86/mach-default/mach_ipi.h
===================================================================
--- linux-2.6.git.orig/include/asm-x86/mach-default/mach_ipi.h
+++ linux-2.6.git/include/asm-x86/mach-default/mach_ipi.h
@@ -13,9 +13,9 @@
 #include <asm/genapic.h>
 #define send_IPI_mask (genapic->send_IPI_mask)
 #else
-static inline void send_IPI_mask(cpumask_t mask, int vector)
+static inline void send_IPI_mask(cpumask_t *mask, int vector)
 {
-	send_IPI_mask_bitmask(mask, vector);
+	send_IPI_mask_bitmask(*mask, vector);
 }
 #endif
 
@@ -25,15 +25,17 @@
 		cpumask_t mask = cpu_online_map;
 
 		cpu_clear(smp_processor_id(), mask);
-		send_IPI_mask(mask, vector);
+		send_IPI_mask(&mask, vector);
 	} else
 		__send_IPI_shortcut(APIC_DEST_ALLBUT, vector);
 }
 
 static inline void __local_send_IPI_all(int vector)
 {
+	cpumask_t mask = cpu_online_map;
+
 	if (no_broadcast || vector == NMI_VECTOR)
-		send_IPI_mask(cpu_online_map, vector);
+		send_IPI_mask(&mask, vector);
 	else
 		__send_IPI_shortcut(APIC_DEST_ALLINC, vector);
 }
Index: linux-2.6.git/include/asm-x86/smp.h
===================================================================
--- linux-2.6.git.orig/include/asm-x86/smp.h
+++ linux-2.6.git/include/asm-x86/smp.h
@@ -53,7 +53,7 @@
 	void (*smp_send_stop)(void);
 	void (*smp_send_reschedule)(int cpu);
 
-	void (*send_call_func_ipi)(cpumask_t mask);
+	void (*send_call_func_ipi)(cpumask_t *mask);
 	void (*send_call_func_single_ipi)(int cpu);
 };
 
@@ -101,7 +101,7 @@
 	smp_ops.send_call_func_single_ipi(cpu);
 }
 
-static inline void arch_send_call_function_ipi(cpumask_t mask)
+static inline void arch_send_call_function_ipi(cpumask_t *mask)
 {
 	smp_ops.send_call_func_ipi(mask);
 }
@@ -110,7 +110,7 @@
 void native_smp_prepare_cpus(unsigned int max_cpus);
 void native_smp_cpus_done(unsigned int max_cpus);
 int native_cpu_up(unsigned int cpunum);
-void native_send_call_func_ipi(cpumask_t mask);
+void native_send_call_func_ipi(cpumask_t *mask);
 void native_send_call_func_single_ipi(int cpu);
 
 extern int __cpu_disable(void);
Index: linux-2.6.git/include/linux/smp.h
===================================================================
--- linux-2.6.git.orig/include/linux/smp.h
+++ linux-2.6.git/include/linux/smp.h
@@ -62,7 +62,7 @@
  * Call a function on all other processors
  */
 int smp_call_function(void(*func)(void *info), void *info, int wait);
-int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
+int smp_call_function_mask(cpumask_t *mask, void(*func)(void *info), void *info,
 				int wait);
 int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
 				int wait);
Index: linux-2.6.git/kernel/smp.c
===================================================================
--- linux-2.6.git.orig/kernel/smp.c
+++ linux-2.6.git/kernel/smp.c
@@ -318,7 +318,7 @@
  * hardware interrupt handler or from a bottom half handler. Preemption
  * must be disabled when calling this function.
  */
-int smp_call_function_mask(cpumask_t mask, void (*func)(void *), void *info,
+int smp_call_function_mask(cpumask_t *mask, void (*func)(void *), void *info,
 			   int wait)
 {
 	struct call_function_data d;
@@ -334,8 +334,8 @@
 	cpu = smp_processor_id();
 	allbutself = cpu_online_map;
 	cpu_clear(cpu, allbutself);
-	cpus_and(mask, mask, allbutself);
-	num_cpus = cpus_weight(mask);
+	cpus_and(*mask, *mask, allbutself);
+	num_cpus = cpus_weight(*mask);
 
 	/*
 	 * If zero CPUs, return. If just a single CPU, turn this request
@@ -344,7 +344,7 @@
 	if (!num_cpus)
 		return 0;
 	else if (num_cpus == 1) {
-		cpu = first_cpu(mask);
+		cpu = first_cpu(*mask);
 		return smp_call_function_single(cpu, func, info, wait);
 	}
 
@@ -364,7 +364,7 @@
 	data->csd.func = func;
 	data->csd.info = info;
 	data->refs = num_cpus;
-	data->cpumask = mask;
+	data->cpumask = *mask;
 
 	spin_lock_irqsave(&call_function_lock, flags);
 	list_add_tail_rcu(&data->csd.list, &call_function_queue);
@@ -377,7 +377,7 @@
 	if (wait) {
 		csd_flag_wait(&data->csd);
 		if (unlikely(slowpath))
-			smp_call_function_mask_quiesce_stack(mask);
+			smp_call_function_mask_quiesce_stack(*mask);
 	}
 
 	return 0;
@@ -402,9 +402,10 @@
 int smp_call_function(void (*func)(void *), void *info, int wait)
 {
 	int ret;
+	cpumask_t tmp_online_map = cpu_online_map;
 
 	preempt_disable();
-	ret = smp_call_function_mask(cpu_online_map, func, info, wait);
+	ret = smp_call_function_mask(&tmp_online_map, func, info, wait);
 	preempt_enable();
 	return ret;
 }
Index: linux-2.6.git/virt/kvm/kvm_main.c
===================================================================
--- linux-2.6.git.orig/virt/kvm/kvm_main.c
+++ linux-2.6.git/virt/kvm/kvm_main.c
@@ -124,7 +124,7 @@
 	if (cpus_empty(cpus))
 		goto out;
 	++kvm->stat.remote_tlb_flush;
-	smp_call_function_mask(cpus, ack_flush, NULL, 1);
+	smp_call_function_mask(&cpus, ack_flush, NULL, 1);
 out:
 	put_cpu();
 }
@@ -149,7 +149,7 @@
 	}
 	if (cpus_empty(cpus))
 		goto out;
-	smp_call_function_mask(cpus, ack_flush, NULL, 1);
+	smp_call_function_mask(&cpus, ack_flush, NULL, 1);
 out:
 	put_cpu();
 }

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Al Viro]

On Tue, Sep 02, 2008 at 09:26:43AM +0200, Jens Axboe wrote:
> > Actually both interfaces are a fscking disaster.  The right things to
> > pass is neither and inode nor a file but a struct block_device.  Al had
> > all this work done a while and it just needs rebasing to a current tree:
> > 
> > 	http://git.kernel.org/?p=linux/kernel/git/viro/bdev.git;a=summary
> 
> Completely agreed. Al, I remember talking to you about this at the
> storage summit back in february. What are your current plans wrt moving
> this forward?

Rebased, with nfs parts of fmode_t patch taken out (irrelevant for
bdev anyway and really better off in intent-killing queue).  Other
than that, it's a straight port...  Same place, same branch.

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Jens Axboe]

On Wed, Sep 03 2008, Al Viro wrote:
> On Tue, Sep 02, 2008 at 09:26:43AM +0200, Jens Axboe wrote:
> > > Actually both interfaces are a fscking disaster.  The right things to
> > > pass is neither and inode nor a file but a struct block_device.  Al had
> > > all this work done a while and it just needs rebasing to a current tree:
> > > 
> > > 	http://git.kernel.org/?p=linux/kernel/git/viro/bdev.git;a=summary
> > 
> > Completely agreed. Al, I remember talking to you about this at the
> > storage summit back in february. What are your current plans wrt moving
> > this forward?
> 
> Rebased, with nfs parts of fmode_t patch taken out (irrelevant for
> bdev anyway and really better off in intent-killing queue).  Other
> than that, it's a straight port...  Same place, same branch.

So what's your plan with this - 2.6.28?

-- 
Jens Axboe

Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26

[Al Viro]

On Thu, Sep 04, 2008 at 12:13:27PM +0200, Jens Axboe wrote:
> On Wed, Sep 03 2008, Al Viro wrote:
> > On Tue, Sep 02, 2008 at 09:26:43AM +0200, Jens Axboe wrote:
> > > > Actually both interfaces are a fscking disaster.  The right things to
> > > > pass is neither and inode nor a file but a struct block_device.  Al had
> > > > all this work done a while and it just needs rebasing to a current tree:
> > > > 
> > > > 	http://git.kernel.org/?p=linux/kernel/git/viro/bdev.git;a=summary
> > > 
> > > Completely agreed. Al, I remember talking to you about this at the
> > > storage summit back in february. What are your current plans wrt moving
> > > this forward?
> > 
> > Rebased, with nfs parts of fmode_t patch taken out (irrelevant for
> > bdev anyway and really better off in intent-killing queue).  Other
> > than that, it's a straight port...  Same place, same branch.
> 
> So what's your plan with this - 2.6.28?

Yes.  The only nastiness is around drivers/ide - there it gets a bunch of
annoying conflicts from the ide-{disk,floppy}_ioctl.c splitoff.  Other than
that, it's trivially ported on top of current linux-next.  Merge order is
going to be interesting - depending on whether block merge happens before
or after ide one.

I'm going to put linux-next-based series on kernel.org tonight, before
going to Portland...

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Rusty Russell]

On Wednesday 27 August 2008 02:51:46 Linus Torvalds wrote:
> On Tue, 26 Aug 2008, Yinghai Lu wrote:
> > wonder if could use "unsigned long *" directly.
>
> I would actually suggest something like this:
>
>  - we continue to have a magic "cpumask_t".
>
>  - we do different cases for big and small NR_CPUS:
>
> 	#if NR_CPUS <= BITS_PER_LONG
>
> 	/*
> 	 * Make it an array - that way passing it as an argument will
> 	 * always pass it as a pointer!
> 	 */
> 	typedef unsigned long cpumask_t[1];
>
> 	static inline void create_cpumask(cpumask_t *p)
> 	{
> 		*p = 0;
> 	}
> 	static inline void free_cpumask(cpumask_t *p)
> 	{
> 	}
>
> 	#else
>
> 	typedef unsigned long *cpumask_t;
>
> 	static inline void create_cpumask(cpumask_t *p)
> 	{
> 		*p = kcalloc(..);
> 	}
>
> 	static inline void free_cpumask(cpumask_t *p)
> 	{
> 		kfree(*p);
> 	}
>
> 	#endif
>
> and now after you do this, you can just do something like
>
> 	cpumask_t mycpu;
>
> 	create_cpumask(&mycpu);
> 	..
> 	free_cpumask(&mycpu);
>
> and in between, you can use 'cpumask' as a pointer, because even when it
> is an array directly allocated on the stack, the array can always
> degenerate into a pointer by C type rules!

Hi Linus,

    This turns out to be awful in practice, mainly due to const.  Consider:

	#ifdef CONFIG_CPUMASK_OFFSTACK
	typedef unsigned long *cpumask_t;
	#else
	typedef unsigned long cpumask_t[1];
	#endif

	cpumask_t returns_cpumask(void);

That's obviously illegal if cpumask_t is an array.  So we need a typedef which 
says "really always a pointer".

	typedef unsigned long *cpumask_return_t;
	cpumask_return_t returns_cpumask(void);

But we usually want it to return a const ptr, and this doesn't work:

	const cpumask_return_t returns_cpumask(void);
	foo.c:12: warning: type qualifiers ignored on function return type

So now we need:
	typedef const unsigned long *cpumask_const_return_t;
	cpumask_const_return_t returns_cpumask(void);

OK, now consider a function which wants to take a const cpu bitmap:

	void cpus_copy(cpumask_t dst, const cpumask_t src);
	...
	cpus_copy(cpus, returns_cpumask());
	foo.c:34: warning: passing argument 2 of ‘cpus_copy’ discards qualifiers from 
pointer target type

Oops, that didn't work with the pointer version.  So we need another typedef:
	#ifdef CONFIG_CPUMASK_OFFSTACK
	typedef const unsigned long *cpumask_const_t;
	#else
	typedef const unsigned long cpumask_const_t[1];
	#endif

	void cpus_copy(cpumask_t dst, cpumask_const_t src);

We end up with this:
	#ifdef CONFIG_CPUMASK_OFFSTACK
	typedef unsigned long *cpumask_t;
	typedef const unsigned long *cpumask_const_t;
	#else
	typedef unsigned long cpumask_t[1];
	typedef const unsigned long cpumask_const_t[1];
	#endif
	typedef unsigned long *cpumask_return_t;
	typedef const unsigned long *cpumask_const_return_t;
	typedef unsigned long cpumask_data_t[1];

I can't see a neater way down this path, and I don't want to lose const.

I can see three alternatives:
1) An ONSTACK_CPUMASK(name) macro which declares "struct cpumask name[1]" or
   "struct cpumask *name".  Same idea as yours, without the typedef.
2) Use a normal struct for cpumask, make everyone use pointers, but have an
   struct cpumask *alloc_stack_cpumask() which uses alloca() for small
   NR_CPUS.
3) Same, but just use kmalloc everywhere.  Optimize important cases by hand.

Anyone see a better way?
Rusty.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Ingo Molnar]

* Rusty Russell <rusty@rustcorp.com.au> wrote:

> I can't see a neater way down this path, and I don't want to lose 
> const.
> 
> I can see three alternatives:
> 1) An ONSTACK_CPUMASK(name) macro which declares "struct cpumask name[1]" or
>    "struct cpumask *name".  Same idea as yours, without the typedef.
> 2) Use a normal struct for cpumask, make everyone use pointers, but have an
>    struct cpumask *alloc_stack_cpumask() which uses alloca() for small
>    NR_CPUS.
> 3) Same, but just use kmalloc everywhere.  Optimize important cases by hand.
> 
> Anyone see a better way?

since most of the important cpumasks in high-perf codepaths are already 
pre-constructed and embedded in some existing object (say task_struct), 
i think a variant of #3 is the best approach:

 - get rid of cpumask_t and use 'struct cpumask' everywhere.

 - do not expose normal kernel code to struct cpumask's definition, only
   declare the type via 'struct cpumask;' in sched.h - a'la 
   kmem_cache_t.

 - even hide the structure from sched.h - use an extra indirection for 
   struct cpumask *cpus_allowed in task_struct and be done with it.

 - have normal cpumask object alloc/free codepaths.

 - optimize any remaining important cases by hand, if needed. (the 
   scheduler mostly)

(wrt. #2, alloca() is a nightmare i think.)

	Ingo

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Thu, 25 Sep 2008, Rusty Russell wrote:
> 
>     This turns out to be awful in practice, mainly due to const.  Consider:
> 
> 	#ifdef CONFIG_CPUMASK_OFFSTACK
> 	typedef unsigned long *cpumask_t;
> 	#else
> 	typedef unsigned long cpumask_t[1];
> 	#endif
> 
> 	cpumask_t returns_cpumask(void);

No. That's already broken. You cannot return a cpumask_t, regardless of 
interface. We must not do it regardless of how we pass those things 
around, since it generates _yet_ another temporary on the stack for the 
return slot for any kind of structure.

So all cpumask functions should always return pointers and/or take 
pointers to be filled in. That's true *regardless* of how we actually are 
to then allocate them.

So forget returning cpumasks. It's irrelevant.

What _is_ relevant is how we allocate them when we need temporary CPU 
masks. And _that_ is where my suggestion comes in. For small NR_CPUS, we 
really do want to allocate them on the stack, because calling kmalloc for 
a 4- or 8-byte allocation is just _stupid_.

So all your arguments are invalid, because you're looking at the wrong 
thing. The thing that I was talking about is converting current code that 
has

   random_function(..)
   {
	cpumask_t mask;

	.. do something with mask ...
   }

which has to be converted some way. And I think it needs to be converted 
in a way that does *not* force us to call kmalloc() for idiotically small 
values.

			Linus

Subject: [RFC 1/1] cpumask: Provide new cpumask API

[Mike Travis]

Linus Torvalds wrote:
> 
> On Thu, 25 Sep 2008, Rusty Russell wrote:
>>     This turns out to be awful in practice, mainly due to const.  Consider:
>>
>> 	#ifdef CONFIG_CPUMASK_OFFSTACK
>> 	typedef unsigned long *cpumask_t;
>> 	#else
>> 	typedef unsigned long cpumask_t[1];
>> 	#endif
>>
>> 	cpumask_t returns_cpumask(void);
> 
> No. That's already broken. You cannot return a cpumask_t, regardless of 
> interface. We must not do it regardless of how we pass those things 
> around, since it generates _yet_ another temporary on the stack for the 
> return slot for any kind of structure.
> 
> So all cpumask functions should always return pointers and/or take 
> pointers to be filled in. That's true *regardless* of how we actually are 
> to then allocate them.
> 
> So forget returning cpumasks. It's irrelevant.
> 
> What _is_ relevant is how we allocate them when we need temporary CPU 
> masks. And _that_ is where my suggestion comes in. For small NR_CPUS, we 
> really do want to allocate them on the stack, because calling kmalloc for 
> a 4- or 8-byte allocation is just _stupid_.
> 
> So all your arguments are invalid, because you're looking at the wrong 
> thing. The thing that I was talking about is converting current code that 
> has
> 
>    random_function(..)
>    {
> 	cpumask_t mask;
> 
> 	.. do something with mask ...
>    }
> 
> which has to be converted some way. And I think it needs to be converted 
> in a way that does *not* force us to call kmalloc() for idiotically small 
> values.
> 
> 			Linus


Subject: [RFC 1/1] cpumask: Provide new cpumask API

Provide new cpumask interface API.  The relevant change is basically
cpumask becomes an opaque object.  I believe this results in the
minimum amount of editing while still allowing the inline cpumask
functions, and the ability to declare static cpumask objects.


    /* raw declaration */
    struct __cpumask_data_s { DECLARE_BITMAP(bits, NR_CPUS); };

    /* cpumask_map_t used for declaring static cpumask maps */
    typedef struct __cpumask_data_s cpumask_map_t[1];

    /* cpumask_t used for function args and return pointers */
    typedef struct __cpumask_data_s *cpumask_t;

    /* cpumask_var_t used for local variable */
    typedef struct __cpumask_data_s	cpumask_var_t[1]; /* SMALL NR_CPUS */
    typedef struct __cpumask_data_s	*cpumask_var_t;	  /* LARGE NR_CPUS */

    /* replaces cpumask_t dst = (cpumask_t)src */
    void cpus_copy(cpumask_t dst, const cpumask_t src);

Remove the '*' indirection in all references to cpumask_t objects.  You can
change the reference to the cpumask object but not the cpumask object itself
without using the functions that operate on cpumask objects (f.e. the cpu_*
operators).  Functions can return a cpumask_t (which is a pointer to the
cpumask object) and only be passed a cpumask_t.

All uses of cpumask_t on the stack are changed to be cpumask_var_t. 
Allocation of local cpumask objects will follow...

All cpumask operators now operate using nr_cpu_ids instead of NR_CPUS.  All
variants of the cpumask operators which used nr_cpu_ids instead of NR_CPUS
are deleted.

All variants of functions which use the (old cpumask_t *) pointer are deleted
(f.e. set_cpus_allowed_ptr()).

Based on code from Rusty Russell <rusty@rustcorp.com.au> (THANKS!!)

Signed-of-by: Mike Travis <travis@sgi.com>

---
 include/linux/cpumask.h |  340 ++++++++++++++++++++++++------------------------
 1 file changed, 174 insertions(+), 166 deletions(-)

--- struct-cpumasks.orig/include/linux/cpumask.h
+++ struct-cpumasks/include/linux/cpumask.h
@@ -3,7 +3,8 @@
 
 /*
  * Cpumasks provide a bitmap suitable for representing the
- * set of CPU's in a system, one bit position per CPU number.
+ * set of CPU's in a system, one bit position per CPU number up to
+ * nr_cpu_ids (<= NR_CPUS).
  *
  * See detailed comments in the file linux/bitmap.h describing the
  * data type on which these cpumasks are based.
@@ -18,18 +19,6 @@
  * For details of cpus_fold(), see bitmap_fold in lib/bitmap.c.
  *
  * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
- * Note: The alternate operations with the suffix "_nr" are used
- *       to limit the range of the loop to nr_cpu_ids instead of
- *       NR_CPUS when NR_CPUS > 64 for performance reasons.
- *       If NR_CPUS is <= 64 then most assembler bitmask
- *       operators execute faster with a constant range, so
- *       the operator will continue to use NR_CPUS.
- *
- *       Another consideration is that nr_cpu_ids is initialized
- *       to NR_CPUS and isn't lowered until the possible cpus are
- *       discovered (including any disabled cpus).  So early uses
- *       will span the entire range of NR_CPUS.
- * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
  *
  * The available cpumask operations are:
  *
@@ -37,6 +26,7 @@
  * void cpu_clear(cpu, mask)		turn off bit 'cpu' in mask
  * void cpus_setall(mask)		set all bits
  * void cpus_clear(mask)		clear all bits
+ * void cpus_copy(dst, src)		copies cpumask bits from src to dst
  * int cpu_isset(cpu, mask)		true iff bit 'cpu' set in mask
  * int cpu_test_and_set(cpu, mask)	test and set bit 'cpu' in mask
  *
@@ -52,17 +42,17 @@
  * int cpus_empty(mask)			Is mask empty (no bits sets)?
  * int cpus_full(mask)			Is mask full (all bits sets)?
  * int cpus_weight(mask)		Hamming weigh - number of set bits
- * int cpus_weight_nr(mask)		Same using nr_cpu_ids instead of NR_CPUS
  *
  * void cpus_shift_right(dst, src, n)	Shift right
  * void cpus_shift_left(dst, src, n)	Shift left
  *
- * int first_cpu(mask)			Number lowest set bit, or NR_CPUS
- * int next_cpu(cpu, mask)		Next cpu past 'cpu', or NR_CPUS
- * int next_cpu_nr(cpu, mask)		Next cpu past 'cpu', or nr_cpu_ids
+ * int first_cpu(mask)			Number lowest set bit, or nr_cpu_ids
+ * int next_cpu(cpu, mask)		Next cpu past 'cpu', or nr_cpu_ids
+ *
+ * cpumask_t cpumask_of_cpu(cpu)	Return pointer to cpumask with bit
+ *					'cpu' set
  *
- * cpumask_t cpumask_of_cpu(cpu)	Return cpumask with bit 'cpu' set
- *					(can be used as an lvalue)
+ * cpu_mask_all				cpumask_map_t of all bits set
  * CPU_MASK_ALL				Initializer - all bits set
  * CPU_MASK_NONE			Initializer - no bits set
  * unsigned long *cpus_addr(mask)	Array of unsigned long's in mask
@@ -76,8 +66,7 @@
  * void cpus_onto(dst, orig, relmap)	*dst = orig relative to relmap
  * void cpus_fold(dst, orig, sz)	dst bits = orig bits mod sz
  *
- * for_each_cpu_mask(cpu, mask)		for-loop cpu over mask using NR_CPUS
- * for_each_cpu_mask_nr(cpu, mask)	for-loop cpu over mask using nr_cpu_ids
+ * for_each_cpu_mask(cpu, mask)		for-loop cpu over mask
  *
  * int num_online_cpus()		Number of online CPUs
  * int num_possible_cpus()		Number of all possible CPUs
@@ -107,129 +96,209 @@
 #include <linux/threads.h>
 #include <linux/bitmap.h>
 
-typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
-extern cpumask_t _unused_cpumask_arg_;
+/* raw declaration */
+struct __cpumask_data_s { DECLARE_BITMAP(bits, NR_CPUS); };
+
+/* cpumask_map_t used for declaring static cpumask maps */
+typedef struct __cpumask_data_s cpumask_map_t[1];
+
+/* cpumask_t used for function args and return pointers */
+typedef struct __cpumask_data_s *cpumask_t;
+
+/* cpumask_var_t used for local variable, definition follows */
+
+#if NR_CPUS == 1
+
+/* cpumask_var_t used for local variable */
+typedef struct __cpumask_data_s	cpumask_var_t[1];
+
+#define nr_cpu_ids		1
+#define first_cpu(src)		({ (void)(src); 0; })
+#define next_cpu(n, src)	({ (void)(src); 1; })
+#define any_online_cpu(mask)	0
+#define for_each_cpu_mask(cpu, mask)	\
+	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
+
+#define num_online_cpus()	1
+#define num_possible_cpus()	1
+#define num_present_cpus()	1
+#define cpu_online(cpu)		((cpu) == 0)
+#define cpu_possible(cpu)	((cpu) == 0)
+#define cpu_present(cpu)	((cpu) == 0)
+#define cpu_active(cpu)		((cpu) == 0)
+
+#else /* ... NR_CPUS > 1 */
+
+#ifdef CONFIG_CPUMASKS_ONSTACK
+
+/* Constant is usually more efficient than a variable for small NR_CPUS */
+#define nr_cpu_ids		NR_CPUS
+typedef struct __cpumask_data_s	cpumask_var_t[1];
+static inline int cpumask_size(void)
+{
+	return sizeof(struct __cpumask_data_s);
+}
+
+#else
+
+/* Starts at NR_CPUS until acpi code discovers actual number. */
+extern int nr_cpu_ids;
+typedef struct __cpumask_data_s	*cpumask_var_t;
+static inline int cpumask_size(void)
+{
+	return sizeof BITS_TO_LONGS(nr_cpu_ids) * sizeof(long);
+}
+
+#endif /* NR_CPUS > BITS_PER_LONG */
+
+int __first_cpu(const cpumask_t srcp);
+int __next_cpu(int n, const cpumask_t srcp);
+int __any_online_cpu(const cpumask_t mask);
+
+#define first_cpu(src)		__first_cpu((src))
+#define next_cpu(n, src)	__next_cpu((n), (src))
+#define any_online_cpu(mask) __any_online_cpu((mask))
+
+#define for_each_cpu_mask(cpu, mask)			\
+	for ((cpu) = -1;				\
+		(cpu) = next_cpu((cpu), (mask)),	\
+		(cpu) < nr_cpu_ids; )
+
+#define num_online_cpus()	cpus_weight(cpu_online_map)
+#define num_possible_cpus()	cpus_weight(cpu_possible_map)
+#define num_present_cpus()	cpus_weight(cpu_present_map)
+#define cpu_online(cpu)		cpu_isset((cpu), cpu_online_map)
+#define cpu_possible(cpu)	cpu_isset((cpu), cpu_possible_map)
+#define cpu_present(cpu)	cpu_isset((cpu), cpu_present_map)
+#define cpu_active(cpu)		cpu_isset((cpu), cpu_active_map)
+#endif /* NR_CPUS > 1 */
 
-#define cpu_set(cpu, dst) __cpu_set((cpu), &(dst))
-static inline void __cpu_set(int cpu, volatile cpumask_t *dstp)
+#define cpu_set(cpu, dst) __cpu_set((cpu), (dst))
+static inline void __cpu_set(int cpu, volatile cpumask_t dstp)
 {
 	set_bit(cpu, dstp->bits);
 }
 
-#define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst))
-static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp)
+#define cpu_clear(cpu, dst) __cpu_clear((cpu), (dst))
+static inline void __cpu_clear(int cpu, volatile cpumask_t dstp)
 {
 	clear_bit(cpu, dstp->bits);
 }
 
-#define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS)
-static inline void __cpus_setall(cpumask_t *dstp, int nbits)
+#define cpus_setall(dst) __cpus_setall((dst), nr_cpu_ids)
+static inline void __cpus_setall(cpumask_t dstp, int nbits)
 {
 	bitmap_fill(dstp->bits, nbits);
 }
 
-#define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS)
-static inline void __cpus_clear(cpumask_t *dstp, int nbits)
+#define cpus_clear(dst) __cpus_clear((dst), nr_cpu_ids)
+static inline void __cpus_clear(cpumask_t dstp, int nbits)
 {
 	bitmap_zero(dstp->bits, nbits);
 }
 
+#define cpus_copy(dst, src) __cpus_copy((dst), (src), nr_cpu_ids)
+static inline void __cpus_copy(cpumask_t dstp, const cpumask_t srcp, int nbits)
+{
+	bitmap_copy(dstp->bits, srcp->bits, nbits);
+}
+
 /* No static inline type checking - see Subtlety (1) above. */
-#define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits)
+#define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask)->bits)
 
-#define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask))
-static inline int __cpu_test_and_set(int cpu, cpumask_t *addr)
+#define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), (cpumask))
+static inline int __cpu_test_and_set(int cpu, cpumask_t addr)
 {
 	return test_and_set_bit(cpu, addr->bits);
 }
 
-#define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_and(dst, src1, src2) __cpus_and((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_and(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_or(dst, src1, src2) __cpus_or((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_or(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_xor(dst, src1, src2) __cpus_xor((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_xor(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
 #define cpus_andnot(dst, src1, src2) \
-				__cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+				__cpus_andnot((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_andnot(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
-static inline void __cpus_complement(cpumask_t *dstp,
-					const cpumask_t *srcp, int nbits)
+#define cpus_complement(dst, src) __cpus_complement((dst), (src), nr_cpu_ids)
+static inline void __cpus_complement(cpumask_t dstp,
+					const cpumask_t srcp, int nbits)
 {
 	bitmap_complement(dstp->bits, srcp->bits, nbits);
 }
 
-#define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_equal(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_equal(src1, src2) __cpus_equal((src1), (src2), nr_cpu_ids)
+static inline int __cpus_equal(const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	return bitmap_equal(src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_intersects(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_intersects(src1, src2) __cpus_intersects((src1), (src2), nr_cpu_ids)
+static inline int __cpus_intersects(const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	return bitmap_intersects(src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_subset(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_subset(src1, src2) __cpus_subset((src1), (src2), nr_cpu_ids)
+static inline int __cpus_subset(const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	return bitmap_subset(src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_empty(src) __cpus_empty(&(src), NR_CPUS)
-static inline int __cpus_empty(const cpumask_t *srcp, int nbits)
+#define cpus_empty(src) __cpus_empty((src), nr_cpu_ids)
+static inline int __cpus_empty(const cpumask_t srcp, int nbits)
 {
 	return bitmap_empty(srcp->bits, nbits);
 }
 
-#define cpus_full(cpumask) __cpus_full(&(cpumask), NR_CPUS)
-static inline int __cpus_full(const cpumask_t *srcp, int nbits)
+#define cpus_full(cpumask) __cpus_full((cpumask), nr_cpu_ids)
+static inline int __cpus_full(const cpumask_t srcp, int nbits)
 {
 	return bitmap_full(srcp->bits, nbits);
 }
 
-#define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS)
-static inline int __cpus_weight(const cpumask_t *srcp, int nbits)
+#define cpus_weight(cpumask) __cpus_weight((cpumask), nr_cpu_ids)
+static inline int __cpus_weight(const cpumask_t srcp, int nbits)
 {
 	return bitmap_weight(srcp->bits, nbits);
 }
 
 #define cpus_shift_right(dst, src, n) \
-			__cpus_shift_right(&(dst), &(src), (n), NR_CPUS)
-static inline void __cpus_shift_right(cpumask_t *dstp,
-					const cpumask_t *srcp, int n, int nbits)
+			__cpus_shift_right((dst), (src), (n), nr_cpu_ids)
+static inline void __cpus_shift_right(cpumask_t dstp,
+					const cpumask_t srcp, int n, int nbits)
 {
 	bitmap_shift_right(dstp->bits, srcp->bits, n, nbits);
 }
 
 #define cpus_shift_left(dst, src, n) \
-			__cpus_shift_left(&(dst), &(src), (n), NR_CPUS)
-static inline void __cpus_shift_left(cpumask_t *dstp,
-					const cpumask_t *srcp, int n, int nbits)
+			__cpus_shift_left((dst), (src), (n), nr_cpu_ids)
+static inline void __cpus_shift_left(cpumask_t dstp,
+					const cpumask_t srcp, int n, int nbits)
 {
 	bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
 }
@@ -244,11 +313,11 @@ static inline void __cpus_shift_left(cpu
 extern const unsigned long
 	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
 
-static inline const cpumask_t *get_cpu_mask(unsigned int cpu)
+static inline const cpumask_t get_cpu_mask(unsigned int cpu)
 {
 	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
 	p -= cpu / BITS_PER_LONG;
-	return (const cpumask_t *)p;
+	return (const cpumask_t)p;
 }
 
 /*
@@ -256,7 +325,7 @@ static inline const cpumask_t *get_cpu_m
  * gcc optimizes it out (it's a constant) and there's no huge stack
  * variable created:
  */
-#define cpumask_of_cpu(cpu) (*get_cpu_mask(cpu))
+#define cpumask_of_cpu(cpu) (get_cpu_mask(cpu))
 
 
 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
@@ -264,143 +333,100 @@ static inline const cpumask_t *get_cpu_m
 #if NR_CPUS <= BITS_PER_LONG
 
 #define CPU_MASK_ALL							\
-(cpumask_t) { {								\
+(cpumask_map_t) { {							\
 	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
 } }
 
-#define CPU_MASK_ALL_PTR	(&CPU_MASK_ALL)
+#define CPU_MASK_ALL_PTR	((cpumask_t)CPU_MASK_ALL)
 
 #else
 
 #define CPU_MASK_ALL							\
-(cpumask_t) { {								\
+(cpumask_map_t) { {							\
 	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
 	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
 } }
 
 /* cpu_mask_all is in init/main.c */
-extern cpumask_t cpu_mask_all;
-#define CPU_MASK_ALL_PTR	(&cpu_mask_all)
+extern cpumask_map_t cpu_mask_all;
+#define CPU_MASK_ALL_PTR	(cpu_mask_all)
 
 #endif
 
 #define CPU_MASK_NONE							\
-(cpumask_t) { {								\
+(cpumask_map_t) { {							\
 	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
 } }
 
 #define CPU_MASK_CPU0							\
-(cpumask_t) { {								\
+(cpumask_map_t) { {							\
 	[0] =  1UL							\
 } }
 
 #define cpus_addr(src) ((src).bits)
 
 #define cpumask_scnprintf(buf, len, src) \
-			__cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
+			__cpumask_scnprintf((buf), (len), (src), nr_cpu_ids)
 static inline int __cpumask_scnprintf(char *buf, int len,
-					const cpumask_t *srcp, int nbits)
+					const cpumask_t srcp, int nbits)
 {
 	return bitmap_scnprintf(buf, len, srcp->bits, nbits);
 }
 
 #define cpumask_parse_user(ubuf, ulen, dst) \
-			__cpumask_parse_user((ubuf), (ulen), &(dst), NR_CPUS)
+			__cpumask_parse_user((ubuf), (ulen), (dst), nr_cpu_ids)
 static inline int __cpumask_parse_user(const char __user *buf, int len,
-					cpumask_t *dstp, int nbits)
+					cpumask_t dstp, int nbits)
 {
 	return bitmap_parse_user(buf, len, dstp->bits, nbits);
 }
 
 #define cpulist_scnprintf(buf, len, src) \
-			__cpulist_scnprintf((buf), (len), &(src), NR_CPUS)
+			__cpulist_scnprintf((buf), (len), (src), nr_cpu_ids)
 static inline int __cpulist_scnprintf(char *buf, int len,
-					const cpumask_t *srcp, int nbits)
+					const cpumask_t srcp, int nbits)
 {
 	return bitmap_scnlistprintf(buf, len, srcp->bits, nbits);
 }
 
-#define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS)
-static inline int __cpulist_parse(const char *buf, cpumask_t *dstp, int nbits)
+#define cpulist_parse(buf, dst) __cpulist_parse((buf), (dst), nr_cpu_ids)
+static inline int __cpulist_parse(const char *buf, cpumask_t dstp, int nbits)
 {
 	return bitmap_parselist(buf, dstp->bits, nbits);
 }
 
 #define cpu_remap(oldbit, old, new) \
-		__cpu_remap((oldbit), &(old), &(new), NR_CPUS)
+		__cpu_remap((oldbit), (old), (new), nr_cpu_ids)
 static inline int __cpu_remap(int oldbit,
-		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
+		const cpumask_t oldp, const cpumask_t newp, int nbits)
 {
 	return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
 }
 
 #define cpus_remap(dst, src, old, new) \
-		__cpus_remap(&(dst), &(src), &(old), &(new), NR_CPUS)
-static inline void __cpus_remap(cpumask_t *dstp, const cpumask_t *srcp,
-		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
+		__cpus_remap((dst), (src), (old), (new), nr_cpu_ids)
+static inline void __cpus_remap(cpumask_t dstp, const cpumask_t srcp,
+		const cpumask_t oldp, const cpumask_t newp, int nbits)
 {
 	bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
 }
 
 #define cpus_onto(dst, orig, relmap) \
-		__cpus_onto(&(dst), &(orig), &(relmap), NR_CPUS)
-static inline void __cpus_onto(cpumask_t *dstp, const cpumask_t *origp,
-		const cpumask_t *relmapp, int nbits)
+		__cpus_onto((dst), (orig), (relmap), nr_cpu_ids)
+static inline void __cpus_onto(cpumask_t dstp, const cpumask_t origp,
+		const cpumask_t relmapp, int nbits)
 {
 	bitmap_onto(dstp->bits, origp->bits, relmapp->bits, nbits);
 }
 
 #define cpus_fold(dst, orig, sz) \
-		__cpus_fold(&(dst), &(orig), sz, NR_CPUS)
-static inline void __cpus_fold(cpumask_t *dstp, const cpumask_t *origp,
+		__cpus_fold((dst), (orig), sz, nr_cpu_ids)
+static inline void __cpus_fold(cpumask_t dstp, const cpumask_t origp,
 		int sz, int nbits)
 {
 	bitmap_fold(dstp->bits, origp->bits, sz, nbits);
 }
 
-#if NR_CPUS == 1
-
-#define nr_cpu_ids		1
-#define first_cpu(src)		({ (void)(src); 0; })
-#define next_cpu(n, src)	({ (void)(src); 1; })
-#define any_online_cpu(mask)	0
-#define for_each_cpu_mask(cpu, mask)	\
-	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
-
-#else /* NR_CPUS > 1 */
-
-extern int nr_cpu_ids;
-int __first_cpu(const cpumask_t *srcp);
-int __next_cpu(int n, const cpumask_t *srcp);
-int __any_online_cpu(const cpumask_t *mask);
-
-#define first_cpu(src)		__first_cpu(&(src))
-#define next_cpu(n, src)	__next_cpu((n), &(src))
-#define any_online_cpu(mask) __any_online_cpu(&(mask))
-#define for_each_cpu_mask(cpu, mask)			\
-	for ((cpu) = -1;				\
-		(cpu) = next_cpu((cpu), (mask)),	\
-		(cpu) < NR_CPUS; )
-#endif
-
-#if NR_CPUS <= 64
-
-#define next_cpu_nr(n, src)		next_cpu(n, src)
-#define cpus_weight_nr(cpumask)		cpus_weight(cpumask)
-#define for_each_cpu_mask_nr(cpu, mask)	for_each_cpu_mask(cpu, mask)
-
-#else /* NR_CPUS > 64 */
-
-int __next_cpu_nr(int n, const cpumask_t *srcp);
-#define next_cpu_nr(n, src)	__next_cpu_nr((n), &(src))
-#define cpus_weight_nr(cpumask)	__cpus_weight(&(cpumask), nr_cpu_ids)
-#define for_each_cpu_mask_nr(cpu, mask)			\
-	for ((cpu) = -1;				\
-		(cpu) = next_cpu_nr((cpu), (mask)),	\
-		(cpu) < nr_cpu_ids; )
-
-#endif /* NR_CPUS > 64 */
-
 /*
  * The following particular system cpumasks and operations manage
  * possible, present, active and online cpus.  Each of them is a fixed size
@@ -458,33 +484,15 @@ int __next_cpu_nr(int n, const cpumask_t
  *        main(){ set1(3); set2(5); }
  */
 
-extern cpumask_t cpu_possible_map;
-extern cpumask_t cpu_online_map;
-extern cpumask_t cpu_present_map;
-extern cpumask_t cpu_active_map;
-
-#if NR_CPUS > 1
-#define num_online_cpus()	cpus_weight_nr(cpu_online_map)
-#define num_possible_cpus()	cpus_weight_nr(cpu_possible_map)
-#define num_present_cpus()	cpus_weight_nr(cpu_present_map)
-#define cpu_online(cpu)		cpu_isset((cpu), cpu_online_map)
-#define cpu_possible(cpu)	cpu_isset((cpu), cpu_possible_map)
-#define cpu_present(cpu)	cpu_isset((cpu), cpu_present_map)
-#define cpu_active(cpu)		cpu_isset((cpu), cpu_active_map)
-#else
-#define num_online_cpus()	1
-#define num_possible_cpus()	1
-#define num_present_cpus()	1
-#define cpu_online(cpu)		((cpu) == 0)
-#define cpu_possible(cpu)	((cpu) == 0)
-#define cpu_present(cpu)	((cpu) == 0)
-#define cpu_active(cpu)		((cpu) == 0)
-#endif
+extern cpumask_map_t cpu_possible_map;
+extern cpumask_map_t cpu_online_map;
+extern cpumask_map_t cpu_present_map;
+extern cpumask_map_t cpu_active_map;
 
 #define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
 
-#define for_each_possible_cpu(cpu) for_each_cpu_mask_nr((cpu), cpu_possible_map)
-#define for_each_online_cpu(cpu)   for_each_cpu_mask_nr((cpu), cpu_online_map)
-#define for_each_present_cpu(cpu)  for_each_cpu_mask_nr((cpu), cpu_present_map)
+#define for_each_possible_cpu(cpu) for_each_cpu_mask((cpu), cpu_possible_map)
+#define for_each_online_cpu(cpu)   for_each_cpu_mask((cpu), cpu_online_map)
+#define for_each_present_cpu(cpu)  for_each_cpu_mask((cpu), cpu_present_map)
 
 #endif /* __LINUX_CPUMASK_H */

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Rusty Russell]

On Friday 26 September 2008 01:42:13 Linus Torvalds wrote:
> On Thu, 25 Sep 2008, Rusty Russell wrote:
> >     This turns out to be awful in practice, mainly due to const. 
> > Consider:
> >
> > 	#ifdef CONFIG_CPUMASK_OFFSTACK
> > 	typedef unsigned long *cpumask_t;
> > 	#else
> > 	typedef unsigned long cpumask_t[1];
> > 	#endif
> >
> > 	cpumask_t returns_cpumask(void);
>
> No. That's already broken. You cannot return a cpumask_t, regardless of
> interface. We must not do it regardless of how we pass those things
> around, since it generates _yet_ another temporary on the stack for the
> return slot for any kind of structure.

No, for large NR_CPUS, cpumask_t is a pointer as shown.  And we have numerous 
basic functions which return a cpumask_t.  Yes, this is part of the problem.

> What _is_ relevant is how we allocate them when we need temporary CPU
> masks. And _that_ is where my suggestion comes in. For small NR_CPUS, we
> really do want to allocate them on the stack, because calling kmalloc for
> a 4- or 8-byte allocation is just _stupid_.

Right, but cpumask_t is used for far more than stack decls, thus the problems.

I can make a separate "cpumask_stack_t" and use your method tho.  I think that 
might even reduce churn and allow us to do this in parts.

> which has to be converted some way. And I think it needs to be converted
> in a way that does *not* force us to call kmalloc() for idiotically small
> values.

Yeah, got that.  But your suggestion to change cpumask_t turned out horribly 
ugly.

Cheers,
Rusty.

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Rusty Russell wrote:
> On Friday 26 September 2008 01:42:13 Linus Torvalds wrote:
>> On Thu, 25 Sep 2008, Rusty Russell wrote:
>>>     This turns out to be awful in practice, mainly due to const. 
>>> Consider:
>>>
>>> 	#ifdef CONFIG_CPUMASK_OFFSTACK
>>> 	typedef unsigned long *cpumask_t;
>>> 	#else
>>> 	typedef unsigned long cpumask_t[1];
>>> 	#endif
>>>
>>> 	cpumask_t returns_cpumask(void);
>> No. That's already broken. You cannot return a cpumask_t, regardless of
>> interface. We must not do it regardless of how we pass those things
>> around, since it generates _yet_ another temporary on the stack for the
>> return slot for any kind of structure.
> 
> No, for large NR_CPUS, cpumask_t is a pointer as shown.  And we have numerous 
> basic functions which return a cpumask_t.  Yes, this is part of the problem.
> 
>> What _is_ relevant is how we allocate them when we need temporary CPU
>> masks. And _that_ is where my suggestion comes in. For small NR_CPUS, we
>> really do want to allocate them on the stack, because calling kmalloc for
>> a 4- or 8-byte allocation is just _stupid_.
> 
> Right, but cpumask_t is used for far more than stack decls, thus the problems.
> 
> I can make a separate "cpumask_stack_t" and use your method tho.  I think that 
> might even reduce churn and allow us to do this in parts.
> 
>> which has to be converted some way. And I think it needs to be converted
>> in a way that does *not* force us to call kmalloc() for idiotically small
>> values.
> 
> Yeah, got that.  But your suggestion to change cpumask_t turned out horribly 
> ugly.
> 
> Cheers,
> Rusty.

Hi Rusty,

I've gotten some good traction on the changes in the following patch.  About 30%
of the kernel is compiling right now and I'm picking up errors and warnings as
I'm going along.  I think it's doing most of what we need.  Attempting to hide
the cpumask struct definition caused all kinds of problems with the inline
functions and statically declaring cpumask's.

(The following patch is a combination of all the changes to cpumask.h with the
header from the first patch.  I'll send you a complete copy in separate email.)

Thanks,
Mike
--

Subject: [RFC 1/1] cpumask: Provide new cpumask API

Provide new cpumask interface API.  The relevant change is basically
cpumask_t becomes an opaque object.  I believe this results in the
minimum amount of editing while still allowing the inline cpumask
functions, and the ability to declare static cpumask objects.


    /* raw declaration */
    struct __cpumask_data_s { DECLARE_BITMAP(bits, NR_CPUS); };

    /* cpumask_map_t used for declaring static cpumask maps */
    typedef struct __cpumask_data_s cpumask_map_t[1];

    /* cpumask_t used for function args and return pointers */
    typedef struct __cpumask_data_s *cpumask_t;

    /* cpumask_var_t used for local variable, definition follows */
    typedef struct __cpumask_data_s	cpumask_var_t[1]; /* SMALL NR_CPUS */
    typedef struct __cpumask_data_s	*cpumask_var_t;	  /* LARGE NR_CPUS */

    /* replaces cpumask_t dst = (cpumask_t)src */
    void cpus_copy(cpumask_t dst, const cpumask_t src);

Remove the '*' indirection in all references to cpumask_t objects.  You can
change the reference to the cpumask object but not the cpumask object itself
without using the functions that operate on cpumask objects (f.e. the cpu_*
operators).  Functions can return a cpumask_t (which is a pointer to the
cpumask object) and only be passed a cpumask_t.

All uses of cpumask_t on the stack are changed to be cpumask_var_t except
for pointers to static cpumask objects.  Allocation of local (temp) cpumask
objects will follow...

All cpumask operators now operate using nr_cpu_ids instead of NR_CPUS.  All
variants of the cpumask operators which used nr_cpu_ids instead of NR_CPUS
are deleted.

All variants of functions which use the (old cpumask_t *) pointer are deleted
(f.e. set_cpus_allowed_ptr()).

Based on code from Rusty Russell <rusty@rustcorp.com.au> (THANKS!!)

Signed-of-by: Mike Travis <travis@sgi.com>

--- struct-cpumasks.orig/include/linux/cpumask.h	2008-09-25 20:40:59.303546951 -0700
+++ struct-cpumasks/include/linux/cpumask.h	2008-09-25 22:41:00.764472541 -0700
@@ -3,7 +3,8 @@
 
 /*
  * Cpumasks provide a bitmap suitable for representing the
- * set of CPU's in a system, one bit position per CPU number.
+ * set of CPU's in a system, one bit position per CPU number up to
+ * nr_cpu_ids (<= NR_CPUS).
  *
  * See detailed comments in the file linux/bitmap.h describing the
  * data type on which these cpumasks are based.
@@ -18,18 +19,6 @@
  * For details of cpus_fold(), see bitmap_fold in lib/bitmap.c.
  *
  * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
- * Note: The alternate operations with the suffix "_nr" are used
- *       to limit the range of the loop to nr_cpu_ids instead of
- *       NR_CPUS when NR_CPUS > 64 for performance reasons.
- *       If NR_CPUS is <= 64 then most assembler bitmask
- *       operators execute faster with a constant range, so
- *       the operator will continue to use NR_CPUS.
- *
- *       Another consideration is that nr_cpu_ids is initialized
- *       to NR_CPUS and isn't lowered until the possible cpus are
- *       discovered (including any disabled cpus).  So early uses
- *       will span the entire range of NR_CPUS.
- * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
  *
  * The available cpumask operations are:
  *
@@ -37,6 +26,7 @@
  * void cpu_clear(cpu, mask)		turn off bit 'cpu' in mask
  * void cpus_setall(mask)		set all bits
  * void cpus_clear(mask)		clear all bits
+ * void cpus_copy(dst, src)		copies cpumask bits from src to dst
  * int cpu_isset(cpu, mask)		true iff bit 'cpu' set in mask
  * int cpu_test_and_set(cpu, mask)	test and set bit 'cpu' in mask
  *
@@ -52,52 +42,22 @@
  * int cpus_empty(mask)			Is mask empty (no bits sets)?
  * int cpus_full(mask)			Is mask full (all bits sets)?
  * int cpus_weight(mask)		Hamming weigh - number of set bits
- * int cpus_weight_nr(mask)		Same using nr_cpu_ids instead of NR_CPUS
  *
  * void cpus_shift_right(dst, src, n)	Shift right
  * void cpus_shift_left(dst, src, n)	Shift left
  *
- * int first_cpu(mask)			Number lowest set bit, or NR_CPUS
- * int next_cpu(cpu, mask)		Next cpu past 'cpu', or NR_CPUS
- * int next_cpu_nr(cpu, mask)		Next cpu past 'cpu', or nr_cpu_ids
+ * int cpus_first(mask)			Number lowest set bit, or nr_cpu_ids
+ * int cpus_next(cpu, mask)		Next cpu past 'cpu', or nr_cpu_ids
+ * int cpus_next_in(cpu, mask, andmask)	Next cpu in mask & andmask or nr_cpu_ids
+ *
+ * cpumask_t cpumask_of_cpu(cpu)	Return pointer to cpumask with bit
+ *					'cpu' set
  *
- * cpumask_t cpumask_of_cpu(cpu)	Return cpumask with bit 'cpu' set
- *					(can be used as an lvalue)
+ * cpu_mask_all				cpumask_map_t of all bits set
  * CPU_MASK_ALL				Initializer - all bits set
  * CPU_MASK_NONE			Initializer - no bits set
  * unsigned long *cpus_addr(mask)	Array of unsigned long's in mask
  *
- * CPUMASK_ALLOC kmalloc's a structure that is a composite of many cpumask_t
- * variables, and CPUMASK_PTR provides pointers to each field.
- *
- * The structure should be defined something like this:
- * struct my_cpumasks {
- *	cpumask_t mask1;
- *	cpumask_t mask2;
- * };
- *
- * Usage is then:
- *	CPUMASK_ALLOC(my_cpumasks);
- *	CPUMASK_PTR(mask1, my_cpumasks);
- *	CPUMASK_PTR(mask2, my_cpumasks);
- *
- *	--- DO NOT reference cpumask_t pointers until this check ---
- *	if (my_cpumasks == NULL)
- *		"kmalloc failed"...
- *
- * References are now pointers to the cpumask_t variables (*mask1, ...)
- *
- *if NR_CPUS > BITS_PER_LONG
- *   CPUMASK_ALLOC(m)			Declares and allocates struct m *m =
- *						kmalloc(sizeof(*m), GFP_KERNEL)
- *   CPUMASK_FREE(m)			Macro for kfree(m)
- *else
- *   CPUMASK_ALLOC(m)			Declares struct m _m, *m = &_m
- *   CPUMASK_FREE(m)			Nop
- *endif
- *   CPUMASK_PTR(v, m)			Declares cpumask_t *v = &(m->v)
- * ------------------------------------------------------------------------
- *
  * int cpumask_scnprintf(buf, len, mask) Format cpumask for printing
  * int cpumask_parse_user(ubuf, ulen, mask)	Parse ascii string as cpumask
  * int cpulist_scnprintf(buf, len, mask) Format cpumask as list for printing
@@ -107,8 +67,8 @@
  * void cpus_onto(dst, orig, relmap)	*dst = orig relative to relmap
  * void cpus_fold(dst, orig, sz)	dst bits = orig bits mod sz
  *
- * for_each_cpu_mask(cpu, mask)		for-loop cpu over mask using NR_CPUS
- * for_each_cpu_mask_nr(cpu, mask)	for-loop cpu over mask using nr_cpu_ids
+ * for_each_cpu(cpu, mask)		for-loop cpu over mask
+ * for_each_cpu_in(cpu, mask, andmask)	for-loop cpu over mask & andmask
  *
  * int num_online_cpus()		Number of online CPUs
  * int num_possible_cpus()		Number of all possible CPUs
@@ -118,6 +78,7 @@
  * int cpu_possible(cpu)		Is some cpu possible?
  * int cpu_present(cpu)			Is some cpu present (can schedule)?
  *
+ * int any_cpu_in(mask, andmask)	First cpu in mask & andmask
  * int any_online_cpu(mask)		First online cpu in mask
  *
  * for_each_possible_cpu(cpu)		for-loop cpu over cpu_possible_map
@@ -138,129 +99,229 @@
 #include <linux/threads.h>
 #include <linux/bitmap.h>
 
-typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
-extern cpumask_t _unused_cpumask_arg_;
+/* raw declaration */
+struct __cpumask_data_s { DECLARE_BITMAP(bits, NR_CPUS); };
+
+/* cpumask_map_t used for declaring static cpumask maps */
+typedef struct __cpumask_data_s cpumask_map_t[1];
+
+/* cpumask_t used for function args and return pointers */
+typedef struct __cpumask_data_s *cpumask_t;
+
+/* cpumask_var_t used for local variable, definition follows */
+
+#if NR_CPUS == 1
+
+/* cpumask_var_t used for local variable */
+typedef struct __cpumask_data_s	cpumask_var_t[1];
+
+#define nr_cpu_ids			1
+#define cpus_first(src)			({ (void)(src); 0; })
+#define cpus_next(n, src)		({ (void)(src); 1; })
+#define cpus_next_in(n, src, andsrc)	({ (void)(src); 1; })
+#define any_online_cpu(mask)		0
+#define for_each_cpu(cpu, mask)	\
+	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
+#define for_each_cpu_in(cpu, mask, andmask) \
+	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)andmask)
+
+#define num_online_cpus()		1
+#define num_possible_cpus()		1
+#define num_present_cpus()		1
+#define cpu_online(cpu)			((cpu) == 0)
+#define cpu_possible(cpu)		((cpu) == 0)
+#define cpu_present(cpu)		((cpu) == 0)
+#define cpu_active(cpu)			((cpu) == 0)
+
+#else /* ... NR_CPUS > 1 */
+
+#ifdef CONFIG_CPUMASKS_ONSTACK
+
+/* Constant is usually more efficient than a variable for small NR_CPUS */
+#define nr_cpu_ids		NR_CPUS
+
+/* cpumask_var_t used for local variable */
+typedef struct __cpumask_data_s	cpumask_var_t[1];
+static inline int cpumask_size(void)
+{
+	return sizeof(struct __cpumask_data_s);
+}
+
+#else
+
+/* Starts at NR_CPUS until acpi code discovers actual number. */
+extern int nr_cpu_ids;
+
+/* cpumask_var_t used for local variable */
+typedef struct __cpumask_data_s	*cpumask_var_t;
+static inline int cpumask_size(void)
+{
+	return BITS_TO_LONGS(nr_cpu_ids) * sizeof(long);
+}
+
+#endif /* NR_CPUS > BITS_PER_LONG */
+
+/* Deprecated: use for_each_cpu() */
+#define for_each_cpu_mask(cpu, mask)	for_each_cpu(cpu, mask)
+
+/* Deprecated: use cpus_first()/cpus_next() */
+#define first_cpu(src)		cpus_first((src))
+#define next_cpu(n, src)	cpus_next((n), (src))
+
+extern int cpus_first(const cpumask_t srcp);
+extern int cpus_next(int n, const cpumask_t srcp);
+extern int cpus_next_in(int n, const cpumask_t srcp, const cpumask_t andsrc);
+extern int any_cpu_in(const cpumask_t mask);
+
+#define any_online_cpu(mask)	any_cpu_in((const cpumask_t)(mask), \
+					   (const cpumask_t)cpu_online_map)
+
+#define for_each_cpu(cpu, mask)				\
+	for ((cpu) = -1;				\
+		(cpu) = cpus_next((cpu), (mask)),	\
+		(cpu) < nr_cpu_ids; )
+
+#define for_each_cpu_in(cpu, mask, andmask)			\
+	for ((cpu) = -1;					\
+		(cpu) = cpus_next_in((cpu), (mask), (andmask)),	\
+		(cpu) < nr_cpu_ids; )
+
 
-#define cpu_set(cpu, dst) __cpu_set((cpu), &(dst))
-static inline void __cpu_set(int cpu, volatile cpumask_t *dstp)
+#define num_online_cpus()	cpus_weight(cpu_online_map)
+#define num_possible_cpus()	cpus_weight(cpu_possible_map)
+#define num_present_cpus()	cpus_weight(cpu_present_map)
+#define cpu_online(cpu)		cpu_isset((cpu), cpu_online_map)
+#define cpu_possible(cpu)	cpu_isset((cpu), cpu_possible_map)
+#define cpu_present(cpu)	cpu_isset((cpu), cpu_present_map)
+#define cpu_active(cpu)		cpu_isset((cpu), cpu_active_map)
+#endif /* NR_CPUS > 1 */
+
+#define cpu_set(cpu, dst) __cpu_set((cpu), (dst))
+static inline void __cpu_set(int cpu, volatile cpumask_t dstp)
 {
 	set_bit(cpu, dstp->bits);
 }
 
-#define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst))
-static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp)
+#define cpu_clear(cpu, dst) __cpu_clear((cpu), (dst))
+static inline void __cpu_clear(int cpu, volatile cpumask_t dstp)
 {
 	clear_bit(cpu, dstp->bits);
 }
 
-#define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS)
-static inline void __cpus_setall(cpumask_t *dstp, int nbits)
+#define cpus_setall(dst) __cpus_setall((dst), nr_cpu_ids)
+static inline void __cpus_setall(cpumask_t dstp, int nbits)
 {
 	bitmap_fill(dstp->bits, nbits);
 }
 
-#define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS)
-static inline void __cpus_clear(cpumask_t *dstp, int nbits)
+#define cpus_clear(dst) __cpus_clear((dst), nr_cpu_ids)
+static inline void __cpus_clear(cpumask_t dstp, int nbits)
 {
 	bitmap_zero(dstp->bits, nbits);
 }
 
+#define cpus_copy(dst, src) __cpus_copy((dst), (src), nr_cpu_ids)
+static inline void __cpus_copy(cpumask_t dstp, const cpumask_t srcp, int nbits)
+{
+	bitmap_copy(dstp->bits, srcp->bits, nbits);
+}
+
 /* No static inline type checking - see Subtlety (1) above. */
-#define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits)
+#define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask)->bits)
 
-#define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask))
-static inline int __cpu_test_and_set(int cpu, cpumask_t *addr)
+#define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), (cpumask))
+static inline int __cpu_test_and_set(int cpu, cpumask_t addr)
 {
 	return test_and_set_bit(cpu, addr->bits);
 }
 
-#define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_and(dst, src1, src2) __cpus_and((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_and(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_or(dst, src1, src2) __cpus_or((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_or(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_xor(dst, src1, src2) __cpus_xor((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_xor(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
 #define cpus_andnot(dst, src1, src2) \
-				__cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+				__cpus_andnot((dst), (src1), (src2), nr_cpu_ids)
+static inline void __cpus_andnot(cpumask_t dstp, const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
-static inline void __cpus_complement(cpumask_t *dstp,
-					const cpumask_t *srcp, int nbits)
+#define cpus_complement(dst, src) __cpus_complement((dst), (src), nr_cpu_ids)
+static inline void __cpus_complement(cpumask_t dstp,
+					const cpumask_t srcp, int nbits)
 {
 	bitmap_complement(dstp->bits, srcp->bits, nbits);
 }
 
-#define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_equal(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_equal(src1, src2) __cpus_equal((src1), (src2), nr_cpu_ids)
+static inline int __cpus_equal(const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	return bitmap_equal(src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_intersects(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_intersects(src1, src2) __cpus_intersects((src1), (src2), nr_cpu_ids)
+static inline int __cpus_intersects(const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	return bitmap_intersects(src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_subset(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+#define cpus_subset(src1, src2) __cpus_subset((src1), (src2), nr_cpu_ids)
+static inline int __cpus_subset(const cpumask_t src1p,
+					const cpumask_t src2p, int nbits)
 {
 	return bitmap_subset(src1p->bits, src2p->bits, nbits);
 }
 
-#define cpus_empty(src) __cpus_empty(&(src), NR_CPUS)
-static inline int __cpus_empty(const cpumask_t *srcp, int nbits)
+#define cpus_empty(src) __cpus_empty((src), nr_cpu_ids)
+static inline int __cpus_empty(const cpumask_t srcp, int nbits)
 {
 	return bitmap_empty(srcp->bits, nbits);
 }
 
-#define cpus_full(cpumask) __cpus_full(&(cpumask), NR_CPUS)
-static inline int __cpus_full(const cpumask_t *srcp, int nbits)
+#define cpus_full(cpumask) __cpus_full((cpumask), nr_cpu_ids)
+static inline int __cpus_full(const cpumask_t srcp, int nbits)
 {
 	return bitmap_full(srcp->bits, nbits);
 }
 
-#define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS)
-static inline int __cpus_weight(const cpumask_t *srcp, int nbits)
+#define cpus_weight(cpumask) __cpus_weight((cpumask), nr_cpu_ids)
+static inline int __cpus_weight(const cpumask_t srcp, int nbits)
 {
 	return bitmap_weight(srcp->bits, nbits);
 }
 
 #define cpus_shift_right(dst, src, n) \
-			__cpus_shift_right(&(dst), &(src), (n), NR_CPUS)
-static inline void __cpus_shift_right(cpumask_t *dstp,
-					const cpumask_t *srcp, int n, int nbits)
+			__cpus_shift_right((dst), (src), (n), nr_cpu_ids)
+static inline void __cpus_shift_right(cpumask_t dstp,
+					const cpumask_t srcp, int n, int nbits)
 {
 	bitmap_shift_right(dstp->bits, srcp->bits, n, nbits);
 }
 
 #define cpus_shift_left(dst, src, n) \
-			__cpus_shift_left(&(dst), &(src), (n), NR_CPUS)
-static inline void __cpus_shift_left(cpumask_t *dstp,
-					const cpumask_t *srcp, int n, int nbits)
+			__cpus_shift_left((dst), (src), (n), nr_cpu_ids)
+static inline void __cpus_shift_left(cpumask_t dstp,
+					const cpumask_t srcp, int n, int nbits)
 {
 	bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
 }
@@ -275,11 +336,12 @@ static inline void __cpus_shift_left(cpu
 extern const unsigned long
 	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
 
-static inline const cpumask_t *get_cpu_mask(unsigned int cpu)
+/* XXX - "const" causes: "warning: type qualifiers ignored on function return type" */
+static inline /*const*/ cpumask_t get_cpu_mask(unsigned int cpu)
 {
 	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
 	p -= cpu / BITS_PER_LONG;
-	return (const cpumask_t *)p;
+	return (const cpumask_t)p;
 }
 
 /*
@@ -287,7 +349,7 @@ static inline const cpumask_t *get_cpu_m
  * gcc optimizes it out (it's a constant) and there's no huge stack
  * variable created:
  */
-#define cpumask_of_cpu(cpu) (*get_cpu_mask(cpu))
+#define cpumask_of_cpu(cpu) (get_cpu_mask(cpu))
 
 
 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
@@ -295,152 +357,94 @@ static inline const cpumask_t *get_cpu_m
 #if NR_CPUS <= BITS_PER_LONG
 
 #define CPU_MASK_ALL							\
-(cpumask_t) { {								\
+(cpumask_map_t) { [0] = { {						\
 	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
-} }
-
-#define CPU_MASK_ALL_PTR	(&CPU_MASK_ALL)
+} } }
 
 #else
 
 #define CPU_MASK_ALL							\
-(cpumask_t) { {								\
+(struct __cpumask_data_s) { [0] = { {					\
 	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
 	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
-} }
-
-/* cpu_mask_all is in init/main.c */
-extern cpumask_t cpu_mask_all;
-#define CPU_MASK_ALL_PTR	(&cpu_mask_all)
+} } }
 
 #endif
 
 #define CPU_MASK_NONE							\
-(cpumask_t) { {								\
+(cpumask_map_t) { [0] = { {						\
 	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
-} }
+} } }
 
 #define CPU_MASK_CPU0							\
-(cpumask_t) { {								\
+(cpumask_map_t) { [0] = { {						\
 	[0] =  1UL							\
-} }
+} } }
 
-#define cpus_addr(src) ((src).bits)
-
-#if NR_CPUS > BITS_PER_LONG
-#define	CPUMASK_ALLOC(m)	struct m *m = kmalloc(sizeof(*m), GFP_KERNEL)
-#define	CPUMASK_FREE(m)		kfree(m)
-#else
-#define	CPUMASK_ALLOC(m)	struct m _m, *m = &_m
-#define	CPUMASK_FREE(m)
-#endif
-#define	CPUMASK_PTR(v, m) 	cpumask_t *v = &(m->v)
+#define cpus_addr(src) ((src)->bits)
 
 #define cpumask_scnprintf(buf, len, src) \
-			__cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
+			__cpumask_scnprintf((buf), (len), (src), nr_cpu_ids)
 static inline int __cpumask_scnprintf(char *buf, int len,
-					const cpumask_t *srcp, int nbits)
+					const cpumask_t srcp, int nbits)
 {
 	return bitmap_scnprintf(buf, len, srcp->bits, nbits);
 }
 
 #define cpumask_parse_user(ubuf, ulen, dst) \
-			__cpumask_parse_user((ubuf), (ulen), &(dst), NR_CPUS)
+			__cpumask_parse_user((ubuf), (ulen), (dst), nr_cpu_ids)
 static inline int __cpumask_parse_user(const char __user *buf, int len,
-					cpumask_t *dstp, int nbits)
+					cpumask_t dstp, int nbits)
 {
 	return bitmap_parse_user(buf, len, dstp->bits, nbits);
 }
 
 #define cpulist_scnprintf(buf, len, src) \
-			__cpulist_scnprintf((buf), (len), &(src), NR_CPUS)
+			__cpulist_scnprintf((buf), (len), (src), nr_cpu_ids)
 static inline int __cpulist_scnprintf(char *buf, int len,
-					const cpumask_t *srcp, int nbits)
+					const cpumask_t srcp, int nbits)
 {
 	return bitmap_scnlistprintf(buf, len, srcp->bits, nbits);
 }
 
-#define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS)
-static inline int __cpulist_parse(const char *buf, cpumask_t *dstp, int nbits)
+#define cpulist_parse(buf, dst) __cpulist_parse((buf), (dst), nr_cpu_ids)
+static inline int __cpulist_parse(const char *buf, cpumask_t dstp, int nbits)
 {
 	return bitmap_parselist(buf, dstp->bits, nbits);
 }
 
 #define cpu_remap(oldbit, old, new) \
-		__cpu_remap((oldbit), &(old), &(new), NR_CPUS)
+		__cpu_remap((oldbit), (old), (new), nr_cpu_ids)
 static inline int __cpu_remap(int oldbit,
-		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
+		const cpumask_t oldp, const cpumask_t newp, int nbits)
 {
 	return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
 }
 
 #define cpus_remap(dst, src, old, new) \
-		__cpus_remap(&(dst), &(src), &(old), &(new), NR_CPUS)
-static inline void __cpus_remap(cpumask_t *dstp, const cpumask_t *srcp,
-		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
+		__cpus_remap((dst), (src), (old), (new), nr_cpu_ids)
+static inline void __cpus_remap(cpumask_t dstp, const cpumask_t srcp,
+		const cpumask_t oldp, const cpumask_t newp, int nbits)
 {
 	bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
 }
 
 #define cpus_onto(dst, orig, relmap) \
-		__cpus_onto(&(dst), &(orig), &(relmap), NR_CPUS)
-static inline void __cpus_onto(cpumask_t *dstp, const cpumask_t *origp,
-		const cpumask_t *relmapp, int nbits)
+		__cpus_onto((dst), (orig), (relmap), nr_cpu_ids)
+static inline void __cpus_onto(cpumask_t dstp, const cpumask_t origp,
+		const cpumask_t relmapp, int nbits)
 {
 	bitmap_onto(dstp->bits, origp->bits, relmapp->bits, nbits);
 }
 
 #define cpus_fold(dst, orig, sz) \
-		__cpus_fold(&(dst), &(orig), sz, NR_CPUS)
-static inline void __cpus_fold(cpumask_t *dstp, const cpumask_t *origp,
+		__cpus_fold((dst), (orig), sz, nr_cpu_ids)
+static inline void __cpus_fold(cpumask_t dstp, const cpumask_t origp,
 		int sz, int nbits)
 {
 	bitmap_fold(dstp->bits, origp->bits, sz, nbits);
 }
 
-#if NR_CPUS == 1
-
-#define nr_cpu_ids		1
-#define first_cpu(src)		({ (void)(src); 0; })
-#define next_cpu(n, src)	({ (void)(src); 1; })
-#define any_online_cpu(mask)	0
-#define for_each_cpu_mask(cpu, mask)	\
-	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
-
-#else /* NR_CPUS > 1 */
-
-extern int nr_cpu_ids;
-int __first_cpu(const cpumask_t *srcp);
-int __next_cpu(int n, const cpumask_t *srcp);
-int __any_online_cpu(const cpumask_t *mask);
-
-#define first_cpu(src)		__first_cpu(&(src))
-#define next_cpu(n, src)	__next_cpu((n), &(src))
-#define any_online_cpu(mask) __any_online_cpu(&(mask))
-#define for_each_cpu_mask(cpu, mask)			\
-	for ((cpu) = -1;				\
-		(cpu) = next_cpu((cpu), (mask)),	\
-		(cpu) < NR_CPUS; )
-#endif
-
-#if NR_CPUS <= 64
-
-#define next_cpu_nr(n, src)		next_cpu(n, src)
-#define cpus_weight_nr(cpumask)		cpus_weight(cpumask)
-#define for_each_cpu_mask_nr(cpu, mask)	for_each_cpu_mask(cpu, mask)
-
-#else /* NR_CPUS > 64 */
-
-int __next_cpu_nr(int n, const cpumask_t *srcp);
-#define next_cpu_nr(n, src)	__next_cpu_nr((n), &(src))
-#define cpus_weight_nr(cpumask)	__cpus_weight(&(cpumask), nr_cpu_ids)
-#define for_each_cpu_mask_nr(cpu, mask)			\
-	for ((cpu) = -1;				\
-		(cpu) = next_cpu_nr((cpu), (mask)),	\
-		(cpu) < nr_cpu_ids; )
-
-#endif /* NR_CPUS > 64 */
-
 /*
  * The following particular system cpumasks and operations manage
  * possible, present, active and online cpus.  Each of them is a fixed size
@@ -498,33 +502,16 @@ int __next_cpu_nr(int n, const cpumask_t
  *        main(){ set1(3); set2(5); }
  */
 
-extern cpumask_t cpu_possible_map;
-extern cpumask_t cpu_online_map;
-extern cpumask_t cpu_present_map;
-extern cpumask_t cpu_active_map;
-
-#if NR_CPUS > 1
-#define num_online_cpus()	cpus_weight_nr(cpu_online_map)
-#define num_possible_cpus()	cpus_weight_nr(cpu_possible_map)
-#define num_present_cpus()	cpus_weight_nr(cpu_present_map)
-#define cpu_online(cpu)		cpu_isset((cpu), cpu_online_map)
-#define cpu_possible(cpu)	cpu_isset((cpu), cpu_possible_map)
-#define cpu_present(cpu)	cpu_isset((cpu), cpu_present_map)
-#define cpu_active(cpu)		cpu_isset((cpu), cpu_active_map)
-#else
-#define num_online_cpus()	1
-#define num_possible_cpus()	1
-#define num_present_cpus()	1
-#define cpu_online(cpu)		((cpu) == 0)
-#define cpu_possible(cpu)	((cpu) == 0)
-#define cpu_present(cpu)	((cpu) == 0)
-#define cpu_active(cpu)		((cpu) == 0)
-#endif
+extern cpumask_map_t cpu_possible_map;
+extern cpumask_map_t cpu_online_map;
+extern cpumask_map_t cpu_present_map;
+extern cpumask_map_t cpu_active_map;
+extern cpumask_map_t cpu_mask_all;
 
 #define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
 
-#define for_each_possible_cpu(cpu) for_each_cpu_mask_nr((cpu), cpu_possible_map)
-#define for_each_online_cpu(cpu)   for_each_cpu_mask_nr((cpu), cpu_online_map)
-#define for_each_present_cpu(cpu)  for_each_cpu_mask_nr((cpu), cpu_present_map)
+#define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_map)
+#define for_each_online_cpu(cpu)   for_each_cpu((cpu), cpu_online_map)
+#define for_each_present_cpu(cpu)  for_each_cpu((cpu), cpu_present_map)
 
 #endif /* __LINUX_CPUMASK_H */

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Ingo Molnar]

* Mike Travis <travis@sgi.com> wrote:

> Hi Rusty,
> 
> I've gotten some good traction on the changes in the following patch.  
> About 30% of the kernel is compiling right now and I'm picking up 
> errors and warnings as I'm going along.  I think it's doing most of 
> what we need.  Attempting to hide the cpumask struct definition caused 
> all kinds of problems with the inline functions and statically 
> declaring cpumask's.
> 
> (The following patch is a combination of all the changes to cpumask.h 
> with the header from the first patch.  I'll send you a complete copy 
> in separate email.)

could you please send whatever .c changes you have already, so that we 
can have a look at how the end result will look like? Doesnt have to 
build, i'm just curious about how it looks like in practice, 
semantically.

	Ingo

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Ingo Molnar wrote:
> * Mike Travis <travis@sgi.com> wrote:
> 
>> Hi Rusty,
>>
>> I've gotten some good traction on the changes in the following patch.  
>> About 30% of the kernel is compiling right now and I'm picking up 
>> errors and warnings as I'm going along.  I think it's doing most of 
>> what we need.  Attempting to hide the cpumask struct definition caused 
>> all kinds of problems with the inline functions and statically 
>> declaring cpumask's.
>>
>> (The following patch is a combination of all the changes to cpumask.h 
>> with the header from the first patch.  I'll send you a complete copy 
>> in separate email.)
> 
> could you please send whatever .c changes you have already, so that we 
> can have a look at how the end result will look like? Doesnt have to 
> build, i'm just curious about how it looks like in practice, 
> semantically.
> 
> 	Ingo


I will, and the full "allyesconfig" does compile.  And it's basically a
benign change in that the functionality is still the same.  I'm currently
reordering it a bit to clean it up.

Thanks,
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Ingo Molnar]

* Mike Travis <travis@sgi.com> wrote:

> > could you please send whatever .c changes you have already, so that 
> > we can have a look at how the end result will look like? Doesnt have 
> > to build, i'm just curious about how it looks like in practice, 
> > semantically.
> 
> 
> I will, and the full "allyesconfig" does compile.  And it's basically 
> a benign change in that the functionality is still the same.  I'm 
> currently reordering it a bit to clean it up.

btw., are the resulting instructions also expected to be the same? If 
yes then you might want to verify it all by making sure the md5's of the 
.o's do not change.

(If that's not possible (gcc decides to compile it a bit differently) 
then no big deal, just wanted to mention the possibility.)

	Ingo

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Ingo Molnar wrote:
> * Mike Travis <travis@sgi.com> wrote:
> 
>>> could you please send whatever .c changes you have already, so that 
>>> we can have a look at how the end result will look like? Doesnt have 
>>> to build, i'm just curious about how it looks like in practice, 
>>> semantically.
>>
>> I will, and the full "allyesconfig" does compile.  And it's basically 
>> a benign change in that the functionality is still the same.  I'm 
>> currently reordering it a bit to clean it up.
> 
> btw., are the resulting instructions also expected to be the same? If 
> yes then you might want to verify it all by making sure the md5's of the 
> .o's do not change.
> 
> (If that's not possible (gcc decides to compile it a bit differently) 
> then no big deal, just wanted to mention the possibility.)
> 
> 	Ingo

Well, not exactly... ;-)  It does institute the new API change that specifies
only pointers to cpumask's can be passed to functions and returned from
functions.  I really wanted the default cpumask_t to be a constant so those
instances where the passed in cpumask is used as a read/write temp variable
would be caught.  But it started getting messy.

One pain is:

	typedef struct __cpumask_s *cpumask_t;
	const cpumask_t xxx;

is not the same as:

	typedef const struct __cpumask_s *const_cpumask_t;
	const_cpumask_t xxx;

and I'm not exactly sure why.  It came up when I tried to declare
functions that returned a constant cpumask_t pointer (node_to_cpumask,
cpumask_of_cpu, etc.)

The other major change I'm contemplating is to remove "cpumask_t" completely
(maybe cpumask_ptr_t?).  This would force every instance of cpumask_t to be
examined.  (I found quite a few I had missed in my original edits when I
added the task struct temp cpumask's.)

Oh yeah, one question ... is "current" always valid?

Thanks,
Mike

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Linus Torvalds]

On Tue, 30 Sep 2008, Mike Travis wrote:
> 
> One pain is:
> 
> 	typedef struct __cpumask_s *cpumask_t;
> 	const cpumask_t xxx;
> 
> is not the same as:
> 
> 	typedef const struct __cpumask_s *const_cpumask_t;
> 	const_cpumask_t xxx;
> 
> and I'm not exactly sure why.

Umm. The const has different 

One is

	typedef const struct __cpumask_s *const_cpumask_t;

which becomes

	(const struct __cpumask_s) *

while the other is

	const cpumask_t xxx

which is

	const (struct __cpumask_s *)

and if you look a bit more closely, you'll see that they are _obviously_ 
not the same thing at all.

Quite frankly, I personally do hate typedefs that end up being pointers, 
and used as pointers, without showing that in the source code.

When you do

	type_t a;

	fn(a);

I expect the code to essentially do a pass-by-value. But when the type_t 
is a pointer, that doesn't really work.

Your issue with 'const' is just another version of the same. You don't 
want the _pointer_ to be const, you want what it points _to_ to be const. 
But because you hid the pointerness inside the typedef, you simply cannot 
do that.

The problem with cpumask's, of course, is that for the "small mask" case, 
we really don't want it to be a pointer. So now it's sometimes a pointer 
and sometimes not. The typedef hides that, and I understand why it's a 
good idea, but I'm surprised you didn't understand what the implications 
were for 'const', and I'm now a bit more leery about this whole thing just 
because the typedef ends up hiding so much - it doesn't just hide the 
basic type, it hides a very basic *code* issue.

			Linus

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Mike Travis]

Linus Torvalds wrote:
> 
> On Tue, 30 Sep 2008, Mike Travis wrote:
>> One pain is:
>>
>> 	typedef struct __cpumask_s *cpumask_t;
>> 	const cpumask_t xxx;
>>
>> is not the same as:
>>
>> 	typedef const struct __cpumask_s *const_cpumask_t;
>> 	const_cpumask_t xxx;
>>
>> and I'm not exactly sure why.
> 
> Umm. The const has different 
> 
> One is
> 
> 	typedef const struct __cpumask_s *const_cpumask_t;
> 
> which becomes
> 
> 	(const struct __cpumask_s) *
> 
> while the other is
> 
> 	const cpumask_t xxx
> 
> which is
> 
> 	const (struct __cpumask_s *)
> 
> and if you look a bit more closely, you'll see that they are _obviously_ 
> not the same thing at all.

Thanks, yes that explains what I should have figured out.  (Nice way to
explain it btw... ;-)

> 
> Quite frankly, I personally do hate typedefs that end up being pointers, 
> and used as pointers, without showing that in the source code.
> 
> When you do
> 
> 	type_t a;
> 
> 	fn(a);
> 
> I expect the code to essentially do a pass-by-value. But when the type_t 
> is a pointer, that doesn't really work.

I agree, and as I mentioned, Rusty was working towards an alternative
method of declaring cpumask's which does not hide this.

My goal was to create an (apparent) opaque handle for cpumask_t and modify
the code so all changes to the contents of the cpumask are via functions.

> 
> Your issue with 'const' is just another version of the same. You don't 
> want the _pointer_ to be const, you want what it points _to_ to be const. 
> But because you hid the pointerness inside the typedef, you simply cannot 
> do that.
> 
> The problem with cpumask's, of course, is that for the "small mask" case, 
> we really don't want it to be a pointer. So now it's sometimes a pointer 
> and sometimes not. The typedef hides that, and I understand why it's a 
> good idea, but I'm surprised you didn't understand what the implications 
> were for 'const', and I'm now a bit more leery about this whole thing just 
> because the typedef ends up hiding so much - it doesn't just hide the 
> basic type, it hides a very basic *code* issue.

Perhaps then defining the cpumask as a list of unsigned longs (remove the
outer struct) would play more "naturally".  Lists by definition are always
referenced by pointers.  I have another version of the patchset that shows
this and I'll post just the cpumask.h and doc files.

> 
> 			Linus

Thanks!
Mike

[RFC 1/1] cpumask: New cpumask API - take 2 - use unsigned longs

[Mike Travis]

Mike Travis wrote:
> Linus Torvalds wrote:
...
>> Your issue with 'const' is just another version of the same. You don't 
>> want the _pointer_ to be const, you want what it points _to_ to be const. 
>> But because you hid the pointerness inside the typedef, you simply cannot 
>> do that.
>>
>> The problem with cpumask's, of course, is that for the "small mask" case, 
>> we really don't want it to be a pointer. So now it's sometimes a pointer 
>> and sometimes not. The typedef hides that, and I understand why it's a 
>> good idea, but I'm surprised you didn't understand what the implications 
>> were for 'const', and I'm now a bit more leery about this whole thing just 
>> because the typedef ends up hiding so much - it doesn't just hide the 
>> basic type, it hides a very basic *code* issue.
> 
> Perhaps then defining the cpumask as a list of unsigned longs (remove the
> outer struct) would play more "naturally".  Lists by definition are always
> referenced by pointers.  I have another version of the patchset that shows
> this and I'll post just the cpumask.h and doc files.
...

Here's an alternate proposal for the new cpumask API.  I have not yet begun
the tedious work of making it compile so there may still be some syntax
errors.  (Init/main.c compiles.)  But I believe it more closely adheres to
proper 'C' coding styles.

Thanks,
Mike
--
Subject: cpumask: Provide new cpumask API

[Copied from Documentation/cpumask.txt]

Introduction

Cpumask variables are used to represent (with a single bit) all the
CPU's in a system.  With the prolific increase in the number of CPU's
in a single system image (SSI), managing this large number of cpus has
become an ordeal.  When the limit of CPU's in a system was small, the
cpumask could fit within an integer.  Even with the increase to 128,
a bit pattern was well within a manageable size.  Now with systems
available that have 2048 cores, with hyper-threading there are 4096
cpu threads.  And the number of cpus in an SSI is growing, 16,384 is
right around the corner.  Even desktop systems with only 2 or 4 sockets,
a new generation of Intel processors that have 128 cores per socket will
increase the count of CPU threads tremendously.

Thus the handling of the cpumask that represents this 4096 limit needs
512 bytes, putting pressure on the amount of stack space needed to
accommodate temporary cpumask variables.

The primary goal of the cpumasks API is to accommodate these large
number of cpus without effecting the compactness of Linux for small,
compact systems.


The Changes

Provide new cpumask interface API.  The relevant change is basically
cpumask_t becomes an pointer to a constant list of unsigned longs
and two new typedef's are used for declaring cpumask_t variables,
cpumask_var_t and cpumask_map_t.  This should result in the minimum
amount of modifications while still allowing the inline cpumask
functions, and the ability to declare static cpumask objects.


    /* cpumask_t is used when pointing to a constant cpumask */
    typedef const unsigned long *cpumask_t;

    /* cpumask_map_t used for declaring static cpumask maps */
    typedef unsigned long cpumask_map_t[BITS_TO_LONGS(nr_cpu_ids)];

    /* cpumask_var_t used for read/write cpumask variables */
    typedef unsigned long cpumask_var_t[BITS_TO_LONGS(nr_cpu_ids)];
    							/* SMALL NR_CPUS */
    typedef unsigned long *cpumask_var_t;		/* LARGE NR_CPUS */

    /* replaces cpumask_t dst = (cpumask_t)src */
    void cpus_copy(cpumask_var_t dst, cpumask_t src);

You can change the reference to the cpumask object but to change the
contents of the cpumask object itself you must use the functions that
operate on cpumask objects (f.e. the cpu_* operators).  Functions can
return a cpumask_t (cpumask pointer) and can only be passed a cpumask_t.

All uses of a cpumask_t variable on the stack are changed to be
cpumask_var_t except for pointers to static (read only) cpumask objects.
Allocation of local (temp) cpumask objects use the functions available
in cpumask_alloc.h.  (descriptions to be supplied.)

All cpumask operators now operate using nr_cpu_ids instead of NR_CPUS.
All variants of the cpumask operators which used nr_cpu_ids instead of
NR_CPUS have been deleted.

All variants of functions which use the (old cpumask_t *) pointer have been
deleted (f.e. set_cpus_allowed_ptr()).

Based on code from Rusty Russell <rusty@rustcorp.com.au> (THANKS!!)

Signed-of-by: Mike Travis <travis@sgi.com>

---
 include/linux/cpumask.h       |  432 +++++++++++++++++++-----------------------
 include/linux/cpumask_alloc.h |   58 +++--
 lib/cpumask.c                 |   36 ++-
 3 files changed, 258 insertions(+), 268 deletions(-)

--- longs-cpumasks.orig/include/linux/cpumask.h
+++ longs-cpumasks/include/linux/cpumask.h
@@ -3,7 +3,8 @@
 
 /*
  * Cpumasks provide a bitmap suitable for representing the
- * set of CPU's in a system, one bit position per CPU number.
+ * set of CPU's in a system, one bit position per CPU number up to
+ * nr_cpu_ids (<= NR_CPUS).
  *
  * See detailed comments in the file linux/bitmap.h describing the
  * data type on which these cpumasks are based.
@@ -18,18 +19,6 @@
  * For details of cpus_fold(), see bitmap_fold in lib/bitmap.c.
  *
  * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
- * Note: The alternate operations with the suffix "_nr" are used
- *       to limit the range of the loop to nr_cpu_ids instead of
- *       NR_CPUS when NR_CPUS > 64 for performance reasons.
- *       If NR_CPUS is <= 64 then most assembler bitmask
- *       operators execute faster with a constant range, so
- *       the operator will continue to use NR_CPUS.
- *
- *       Another consideration is that nr_cpu_ids is initialized
- *       to NR_CPUS and isn't lowered until the possible cpus are
- *       discovered (including any disabled cpus).  So early uses
- *       will span the entire range of NR_CPUS.
- * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
  *
  * The available cpumask operations are:
  *
@@ -37,6 +26,7 @@
  * void cpu_clear(cpu, mask)		turn off bit 'cpu' in mask
  * void cpus_setall(mask)		set all bits
  * void cpus_clear(mask)		clear all bits
+ * void cpus_copy(dst, src)		copies cpumask bits from src to dst
  * int cpu_isset(cpu, mask)		true iff bit 'cpu' set in mask
  * int cpu_test_and_set(cpu, mask)	test and set bit 'cpu' in mask
  *
@@ -52,19 +42,21 @@
  * int cpus_empty(mask)			Is mask empty (no bits sets)?
  * int cpus_full(mask)			Is mask full (all bits sets)?
  * int cpus_weight(mask)		Hamming weigh - number of set bits
- * int cpus_weight_nr(mask)		Same using nr_cpu_ids instead of NR_CPUS
  *
  * void cpus_shift_right(dst, src, n)	Shift right
  * void cpus_shift_left(dst, src, n)	Shift left
  *
- * int first_cpu(mask)			Number lowest set bit, or NR_CPUS
- * int next_cpu(cpu, mask)		Next cpu past 'cpu', or NR_CPUS
- * int next_cpu_nr(cpu, mask)		Next cpu past 'cpu', or nr_cpu_ids
- *
- * cpumask_t cpumask_of_cpu(cpu)	Return cpumask with bit 'cpu' set
- *					(can be used as an lvalue)
- * CPU_MASK_ALL				Initializer - all bits set
- * CPU_MASK_NONE			Initializer - no bits set
+ * int cpus_first(mask)			Number lowest set bit, or nr_cpu_ids
+ * int cpus_next(cpu, mask)		Next cpu past 'cpu', or nr_cpu_ids
+ * int cpus_next_in(cpu, mask, andmask)	Next cpu in mask & andmask or nr_cpu_ids
+ *
+ * const cpumask_t cpumask_of_cpu(cpu)	Return pointer to cpumask with bit
+ *					'cpu' set
+ *
+ * cpu_mask_all				cpumask_map_t of all bits set
+ * CPU_MASK_ALL				Initializer only - all bits set
+ * CPU_MASK_NONE			Initializer only - no bits set
+ * CPU_MASK_CPU0			Initializer only - cpu 0 bit set
  * unsigned long *cpus_addr(mask)	Array of unsigned long's in mask
  *
  * int cpumask_scnprintf(buf, len, mask) Format cpumask for printing
@@ -76,8 +68,8 @@
  * void cpus_onto(dst, orig, relmap)	*dst = orig relative to relmap
  * void cpus_fold(dst, orig, sz)	dst bits = orig bits mod sz
  *
- * for_each_cpu_mask(cpu, mask)		for-loop cpu over mask using NR_CPUS
- * for_each_cpu_mask_nr(cpu, mask)	for-loop cpu over mask using nr_cpu_ids
+ * for_each_cpu(cpu, mask)		for-loop cpu over mask
+ * for_each_cpu_in(cpu, mask, andmask)	for-loop cpu over mask & andmask
  *
  * int num_online_cpus()		Number of online CPUs
  * int num_possible_cpus()		Number of all possible CPUs
@@ -87,6 +79,7 @@
  * int cpu_possible(cpu)		Is some cpu possible?
  * int cpu_present(cpu)			Is some cpu present (can schedule)?
  *
+ * int any_cpu_in(mask, andmask)	First cpu in mask & andmask
  * int any_online_cpu(mask)		First online cpu in mask
  *
  * for_each_possible_cpu(cpu)		for-loop cpu over cpu_possible_map
@@ -107,131 +100,200 @@
 #include <linux/threads.h>
 #include <linux/bitmap.h>
 
-typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
-extern cpumask_t _unused_cpumask_arg_;
+#if NR_CPUS == 1
+
+typedef (const unsigned long) *cpumask_t;
+typedef unsigned long cpumask_map_t[1];
+typedef unsigned long cpumask_var_t[1];
+
+#define nr_cpu_ids			1
+#define cpus_first(src)			({ (void)(src); 0; })
+#define cpus_next(n, src)		({ (void)(src); 1; })
+#define cpus_next_in(n, src, andsrc)	({ (void)(src); 1; })
+#define any_online_cpu(mask)		0
+#define for_each_cpu(cpu, mask)	\
+	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
+#define for_each_cpu_in(cpu, mask, andmask) \
+	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)andmask)
+
+#define num_online_cpus()		1
+#define num_possible_cpus()		1
+#define num_present_cpus()		1
+#define cpu_online(cpu)			((cpu) == 0)
+#define cpu_possible(cpu)		((cpu) == 0)
+#define cpu_present(cpu)		((cpu) == 0)
+#define cpu_active(cpu)			((cpu) == 0)
+
+#else /* ... NR_CPUS > 1 */
+
+#ifdef CONFIG_CPUMASKS_OFFSTACK
+
+/* Starts at NR_CPUS until acpi code discovers actual number. */
+extern int nr_cpu_ids;
+typedef unsigned long *cpumask_var_t;
+
+#else /* CPUMASKS "ONSTACK" */
+
+/* Constant is usually more efficient than a variable for small NR_CPUS */
+#define nr_cpu_ids		NR_CPUS
+typedef unsigned long cpumask_var_t[BITS_TO_LONGS(nr_cpu_ids)];
+
+#endif
+
+/* cpumask_t defaults to pointer to constant bit map */
+typedef const unsigned long *cpumask_t;
+typedef unsigned long cpumask_map_t[BITS_TO_LONGS(nr_cpu_ids)];
+
+extern int cpus_first(cpumask_t src);
+extern int cpus_next(int n, cpumask_t src);
+extern int cpus_next_in(int n, cpumask_t src, cpumask_t andsrc);
+extern int any_cpu_in(cpumask_t mask, cpumask_t andmask);
+
+#define any_online_cpu(mask)	any_cpu_in((cpumask_t)(mask), \
+					   (cpumask_t)cpu_online_map)
+
+#define for_each_cpu(cpu, mask)				\
+	for ((cpu) = -1;				\
+		(cpu) = cpus_next((cpu), (mask)),	\
+		(cpu) < nr_cpu_ids; )
+
+#define for_each_cpu_in(cpu, mask, andmask)			\
+	for ((cpu) = -1;					\
+		(cpu) = cpus_next_in((cpu), (mask), (andmask)),	\
+		(cpu) < nr_cpu_ids; )
+
+#define num_online_cpus()	cpus_weight(cpu_online_map)
+#define num_possible_cpus()	cpus_weight(cpu_possible_map)
+#define num_present_cpus()	cpus_weight(cpu_present_map)
+#define cpu_online(cpu)		cpu_isset((cpu), cpu_online_map)
+#define cpu_possible(cpu)	cpu_isset((cpu), cpu_possible_map)
+#define cpu_present(cpu)	cpu_isset((cpu), cpu_present_map)
+#define cpu_active(cpu)		cpu_isset((cpu), cpu_active_map)
+
+#endif /* NR_CPUS > 1 */
+
+/* Deprecated: use for_each_cpu() */
+#define for_each_cpu_mask(cpu, mask)	\
+	for_each_cpu(cpu, mask)
+/*
+ * XXX - how to add this to the above macro?
+ * #warning "for_each_cpu_mask is deprecated, use for_each_cpu"
+ */
+
+/* Deprecated: use cpus_first() */
+static inline int __deprecated first_cpu(cpumask_t src)
+{
+	return cpus_first(src);
+}
+
+/* Deprecated: use cpus_next() */
+static inline int __deprecated next_cpu(int n, cpumask_t src)
+{
+	return cpus_next(n, src);
+}
+
+static inline int cpumask_size(void)
+{
+	return BITS_TO_LONGS(nr_cpu_ids) * sizeof(unsigned long);
+}
 
-#define cpu_set(cpu, dst) __cpu_set((cpu), &(dst))
-static inline void __cpu_set(int cpu, volatile cpumask_t *dstp)
+static inline void cpu_set(int cpu, volatile cpumask_var_t dst)
 {
-	set_bit(cpu, dstp->bits);
+	set_bit(cpu, dst);
 }
 
-#define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst))
-static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp)
+static inline void cpu_clear(int cpu, volatile cpumask_var_t dst)
 {
-	clear_bit(cpu, dstp->bits);
+	clear_bit(cpu, dst);
 }
 
-#define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS)
-static inline void __cpus_setall(cpumask_t *dstp, int nbits)
+static inline void cpus_setall(cpumask_var_t dst)
 {
-	bitmap_fill(dstp->bits, nbits);
+	bitmap_fill(dst, nr_cpu_ids);
 }
 
-#define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS)
-static inline void __cpus_clear(cpumask_t *dstp, int nbits)
+static inline void cpus_clear(cpumask_var_t dst)
 {
-	bitmap_zero(dstp->bits, nbits);
+	bitmap_zero(dst, nr_cpu_ids);
+}
+
+static inline void cpus_copy(cpumask_var_t dst, cpumask_t src)
+{
+	bitmap_copy(dst, src, nr_cpu_ids);
 }
 
 /* No static inline type checking - see Subtlety (1) above. */
-#define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits)
+#define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask))
 
-#define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask))
-static inline int __cpu_test_and_set(int cpu, cpumask_t *addr)
+static inline int cpu_test_and_set(int cpu, cpumask_var_t addr)
 {
-	return test_and_set_bit(cpu, addr->bits);
+	return test_and_set_bit(cpu, addr);
 }
 
-#define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+static inline void cpus_and(cpumask_var_t dst, cpumask_t src1, cpumask_t src2)
 {
-	bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
+	bitmap_and(dst, src1, src2, nr_cpu_ids);
 }
 
-#define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+static inline void cpus_or(cpumask_var_t dst, cpumask_t src1, cpumask_t src2)
 {
-	bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
+	bitmap_or(dst, src1, src2, nr_cpu_ids);
 }
 
-#define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+static inline void cpus_xor(cpumask_var_t dst, cpumask_t src1, cpumask_t src2)
 {
-	bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
+	bitmap_xor(dst, src1, src2, nr_cpu_ids);
 }
 
-#define cpus_andnot(dst, src1, src2) \
-				__cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+static inline void cpus_andnot(cpumask_var_t dst, cpumask_t src1,
+						cpumask_t src2)
 {
-	bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
+	bitmap_andnot(dst, src1, src2, nr_cpu_ids);
 }
 
-#define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
-static inline void __cpus_complement(cpumask_t *dstp,
-					const cpumask_t *srcp, int nbits)
+static inline void cpus_complement(cpumask_var_t dst, cpumask_t src)
 {
-	bitmap_complement(dstp->bits, srcp->bits, nbits);
+	bitmap_complement(dst, src, nr_cpu_ids);
 }
 
-#define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_equal(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+static inline int cpus_equal(cpumask_t src1, cpumask_t src2)
 {
-	return bitmap_equal(src1p->bits, src2p->bits, nbits);
+	return bitmap_equal(src1, src2, nr_cpu_ids);
 }
 
-#define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_intersects(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+static inline int cpus_intersects(cpumask_t src1, cpumask_t src2)
 {
-	return bitmap_intersects(src1p->bits, src2p->bits, nbits);
+	return bitmap_intersects(src1, src2, nr_cpu_ids);
 }
 
-#define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS)
-static inline int __cpus_subset(const cpumask_t *src1p,
-					const cpumask_t *src2p, int nbits)
+static inline int cpus_subset(cpumask_t src1, cpumask_t src2)
 {
-	return bitmap_subset(src1p->bits, src2p->bits, nbits);
+	return bitmap_subset(src1, src2, nr_cpu_ids);
 }
 
-#define cpus_empty(src) __cpus_empty(&(src), NR_CPUS)
-static inline int __cpus_empty(const cpumask_t *srcp, int nbits)
+static inline int cpus_empty(cpumask_t src)
 {
-	return bitmap_empty(srcp->bits, nbits);
+	return bitmap_empty(src, nr_cpu_ids);
 }
 
-#define cpus_full(cpumask) __cpus_full(&(cpumask), NR_CPUS)
-static inline int __cpus_full(const cpumask_t *srcp, int nbits)
+static inline int cpus_full(cpumask_t src)
 {
-	return bitmap_full(srcp->bits, nbits);
+	return bitmap_full(src, nr_cpu_ids);
 }
 
-#define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS)
-static inline int __cpus_weight(const cpumask_t *srcp, int nbits)
+static inline int cpus_weight(cpumask_t src)
 {
-	return bitmap_weight(srcp->bits, nbits);
+	return bitmap_weight(src, nr_cpu_ids);
 }
 
-#define cpus_shift_right(dst, src, n) \
-			__cpus_shift_right(&(dst), &(src), (n), NR_CPUS)
-static inline void __cpus_shift_right(cpumask_t *dstp,
-					const cpumask_t *srcp, int n, int nbits)
+static inline void cpus_shift_right(cpumask_var_t dst, cpumask_t src, int n)
 {
-	bitmap_shift_right(dstp->bits, srcp->bits, n, nbits);
+	bitmap_shift_right(dst, src, n, nr_cpu_ids);
 }
 
-#define cpus_shift_left(dst, src, n) \
-			__cpus_shift_left(&(dst), &(src), (n), NR_CPUS)
-static inline void __cpus_shift_left(cpumask_t *dstp,
-					const cpumask_t *srcp, int n, int nbits)
+static inline void cpus_shift_left(cpumask_var_t dst, cpumask_t src, int n)
 {
-	bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
+	bitmap_shift_left(dst, src, n, nr_cpu_ids);
 }
 
 /*
@@ -244,11 +306,11 @@ static inline void __cpus_shift_left(cpu
 extern const unsigned long
 	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
 
-static inline const cpumask_t *get_cpu_mask(unsigned int cpu)
+static inline cpumask_t get_cpu_mask(unsigned int cpu)
 {
 	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
 	p -= cpu / BITS_PER_LONG;
-	return (const cpumask_t *)p;
+	return (cpumask_t)p;
 }
 
 /*
@@ -256,150 +318,79 @@ static inline const cpumask_t *get_cpu_m
  * gcc optimizes it out (it's a constant) and there's no huge stack
  * variable created:
  */
-#define cpumask_of_cpu(cpu) (*get_cpu_mask(cpu))
-
+#define cpumask_of_cpu(cpu) ((cpumask_t)get_cpu_mask(cpu))
 
 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
+#define	CPU_MASK_INIT(value) {					\
+	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  value		\
+}
 
 #if NR_CPUS <= BITS_PER_LONG
 
-#define CPU_MASK_ALL							\
-(cpumask_t) { {								\
-	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
-} }
-
-#define CPU_MASK_ALL_PTR	(&CPU_MASK_ALL)
+/* Initializer only, use cpu_mask_all in function arguments */
+#define CPU_MASK_ALL CPU_MASK_INIT(CPU_MASK_LAST_WORD)
 
 #else
 
-#define CPU_MASK_ALL							\
-(cpumask_t) { {								\
-	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
-	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
-} }
-
-/* cpu_mask_all is in init/main.c */
-extern cpumask_t cpu_mask_all;
-#define CPU_MASK_ALL_PTR	(&cpu_mask_all)
+/* Initializer only, use cpu_mask_all in function arguments */
+#define CPU_MASK_ALL {						\
+	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,		\
+	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD		\
+}
 
 #endif
 
-#define CPU_MASK_NONE							\
-(cpumask_t) { {								\
-	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
-} }
-
-#define CPU_MASK_CPU0							\
-(cpumask_t) { {								\
-	[0] =  1UL							\
-} }
+/* Initializers only */
+#define CPU_MASK_NONE CPU_MASK_INIT(0UL)
+#define CPU_MASK_CPU0 CPU_MASK_INIT(1UL)
 
-#define cpus_addr(src) ((src).bits)
-
-#define cpumask_scnprintf(buf, len, src) \
-			__cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
-static inline int __cpumask_scnprintf(char *buf, int len,
-					const cpumask_t *srcp, int nbits)
+static inline unsigned long *cpus_addr(cpumask_t src)
 {
-	return bitmap_scnprintf(buf, len, srcp->bits, nbits);
+	return (unsigned long *)src;
 }
 
-#define cpumask_parse_user(ubuf, ulen, dst) \
-			__cpumask_parse_user((ubuf), (ulen), &(dst), NR_CPUS)
-static inline int __cpumask_parse_user(const char __user *buf, int len,
-					cpumask_t *dstp, int nbits)
+static inline int cpumask_scnprintf(char *buf, int len, cpumask_t src)
 {
-	return bitmap_parse_user(buf, len, dstp->bits, nbits);
+	return bitmap_scnprintf(buf, len, src, nr_cpu_ids);
 }
 
-#define cpulist_scnprintf(buf, len, src) \
-			__cpulist_scnprintf((buf), (len), &(src), NR_CPUS)
-static inline int __cpulist_scnprintf(char *buf, int len,
-					const cpumask_t *srcp, int nbits)
+static inline int cpumask_parse_user(const char __user *buf, int len,
+							cpumask_var_t dst)
 {
-	return bitmap_scnlistprintf(buf, len, srcp->bits, nbits);
+	return bitmap_parse_user(buf, len, dst, nr_cpu_ids);
 }
 
-#define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS)
-static inline int __cpulist_parse(const char *buf, cpumask_t *dstp, int nbits)
+static inline int cpulist_scnprintf(char *buf, int len, cpumask_t src)
 {
-	return bitmap_parselist(buf, dstp->bits, nbits);
+	return bitmap_scnlistprintf(buf, len, src, nr_cpu_ids);
 }
 
-#define cpu_remap(oldbit, old, new) \
-		__cpu_remap((oldbit), &(old), &(new), NR_CPUS)
-static inline int __cpu_remap(int oldbit,
-		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
+static inline int cpulist_parse(const char *buf, cpumask_var_t dst)
 {
-	return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
+	return bitmap_parselist(buf, dst, nr_cpu_ids);
 }
 
-#define cpus_remap(dst, src, old, new) \
-		__cpus_remap(&(dst), &(src), &(old), &(new), NR_CPUS)
-static inline void __cpus_remap(cpumask_t *dstp, const cpumask_t *srcp,
-		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
+static inline int cpu_remap(int oldbit, cpumask_t old, cpumask_t new)
 {
-	bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
+	return bitmap_bitremap(oldbit, old, new, nr_cpu_ids);
 }
 
-#define cpus_onto(dst, orig, relmap) \
-		__cpus_onto(&(dst), &(orig), &(relmap), NR_CPUS)
-static inline void __cpus_onto(cpumask_t *dstp, const cpumask_t *origp,
-		const cpumask_t *relmapp, int nbits)
+static inline void cpus_remap(cpumask_var_t dst, cpumask_t src, cpumask_t old,
+								cpumask_t new)
 {
-	bitmap_onto(dstp->bits, origp->bits, relmapp->bits, nbits);
+	bitmap_remap(dst, src, old, new, nr_cpu_ids);
 }
 
-#define cpus_fold(dst, orig, sz) \
-		__cpus_fold(&(dst), &(orig), sz, NR_CPUS)
-static inline void __cpus_fold(cpumask_t *dstp, const cpumask_t *origp,
-		int sz, int nbits)
+static inline void cpus_onto(cpumask_var_t dst, cpumask_t orig,
+						cpumask_t relmap)
 {
-	bitmap_fold(dstp->bits, origp->bits, sz, nbits);
+	bitmap_onto(dst, orig, relmap, nr_cpu_ids);
 }
 
-#if NR_CPUS == 1
-
-#define nr_cpu_ids		1
-#define first_cpu(src)		({ (void)(src); 0; })
-#define next_cpu(n, src)	({ (void)(src); 1; })
-#define any_online_cpu(mask)	0
-#define for_each_cpu_mask(cpu, mask)	\
-	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
-
-#else /* NR_CPUS > 1 */
-
-extern int nr_cpu_ids;
-int __first_cpu(const cpumask_t *srcp);
-int __next_cpu(int n, const cpumask_t *srcp);
-int __any_online_cpu(const cpumask_t *mask);
-
-#define first_cpu(src)		__first_cpu(&(src))
-#define next_cpu(n, src)	__next_cpu((n), &(src))
-#define any_online_cpu(mask) __any_online_cpu(&(mask))
-#define for_each_cpu_mask(cpu, mask)			\
-	for ((cpu) = -1;				\
-		(cpu) = next_cpu((cpu), (mask)),	\
-		(cpu) < NR_CPUS; )
-#endif
-
-#if NR_CPUS <= 64
-
-#define next_cpu_nr(n, src)		next_cpu(n, src)
-#define cpus_weight_nr(cpumask)		cpus_weight(cpumask)
-#define for_each_cpu_mask_nr(cpu, mask)	for_each_cpu_mask(cpu, mask)
-
-#else /* NR_CPUS > 64 */
-
-int __next_cpu_nr(int n, const cpumask_t *srcp);
-#define next_cpu_nr(n, src)	__next_cpu_nr((n), &(src))
-#define cpus_weight_nr(cpumask)	__cpus_weight(&(cpumask), nr_cpu_ids)
-#define for_each_cpu_mask_nr(cpu, mask)			\
-	for ((cpu) = -1;				\
-		(cpu) = next_cpu_nr((cpu), (mask)),	\
-		(cpu) < nr_cpu_ids; )
-
-#endif /* NR_CPUS > 64 */
+static inline void cpus_fold(cpumask_var_t dst, cpumask_t orig, int sz)
+{
+	bitmap_fold(dst, orig, sz, nr_cpu_ids);
+}
 
 /*
  * The following particular system cpumasks and operations manage
@@ -458,33 +449,16 @@ int __next_cpu_nr(int n, const cpumask_t
  *        main(){ set1(3); set2(5); }
  */
 
-extern cpumask_t cpu_possible_map;
-extern cpumask_t cpu_online_map;
-extern cpumask_t cpu_present_map;
-extern cpumask_t cpu_active_map;
-
-#if NR_CPUS > 1
-#define num_online_cpus()	cpus_weight_nr(cpu_online_map)
-#define num_possible_cpus()	cpus_weight_nr(cpu_possible_map)
-#define num_present_cpus()	cpus_weight_nr(cpu_present_map)
-#define cpu_online(cpu)		cpu_isset((cpu), cpu_online_map)
-#define cpu_possible(cpu)	cpu_isset((cpu), cpu_possible_map)
-#define cpu_present(cpu)	cpu_isset((cpu), cpu_present_map)
-#define cpu_active(cpu)		cpu_isset((cpu), cpu_active_map)
-#else
-#define num_online_cpus()	1
-#define num_possible_cpus()	1
-#define num_present_cpus()	1
-#define cpu_online(cpu)		((cpu) == 0)
-#define cpu_possible(cpu)	((cpu) == 0)
-#define cpu_present(cpu)	((cpu) == 0)
-#define cpu_active(cpu)		((cpu) == 0)
-#endif
+extern cpumask_map_t cpu_possible_map;
+extern cpumask_map_t cpu_online_map;
+extern cpumask_map_t cpu_present_map;
+extern cpumask_map_t cpu_active_map;
+extern cpumask_map_t cpu_mask_all;
 
 #define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
 
-#define for_each_possible_cpu(cpu) for_each_cpu_mask_nr((cpu), cpu_possible_map)
-#define for_each_online_cpu(cpu)   for_each_cpu_mask_nr((cpu), cpu_online_map)
-#define for_each_present_cpu(cpu)  for_each_cpu_mask_nr((cpu), cpu_present_map)
+#define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_map)
+#define for_each_online_cpu(cpu)   for_each_cpu((cpu), cpu_online_map)
+#define for_each_present_cpu(cpu)  for_each_cpu((cpu), cpu_present_map)
 
 #endif /* __LINUX_CPUMASK_H */
--- longs-cpumasks.orig/lib/cpumask.c
+++ longs-cpumasks/lib/cpumask.c
@@ -3,34 +3,40 @@
 #include <linux/cpumask.h>
 #include <linux/module.h>
 
-int __first_cpu(const cpumask_t *srcp)
+int cpus_first(cpumask_t srcp)
 {
-	return find_first_bit(srcp->bits, NR_CPUS);
+	return find_first_bit(srcp, nr_cpu_ids);
 }
-EXPORT_SYMBOL(__first_cpu);
+EXPORT_SYMBOL(cpus_first);
 
-int __next_cpu(int n, const cpumask_t *srcp)
+int cpus_next(int n, cpumask_t srcp)
 {
-	return find_next_bit(srcp->bits, NR_CPUS, n+1);
+	return find_next_bit(srcp, nr_cpu_ids, n+1);
 }
-EXPORT_SYMBOL(__next_cpu);
+EXPORT_SYMBOL(cpus_next);
 
-#if NR_CPUS > 64
-int __next_cpu_nr(int n, const cpumask_t *srcp)
+int cpus_next_in(int n, cpumask_t srcp, cpumask_t andp)
 {
-	return find_next_bit(srcp->bits, nr_cpu_ids, n+1);
+	int cpu;
+
+	for (cpu = n + 1; cpu < nr_cpu_ids; cpu++) {
+		cpu = find_next_bit(srcp, nr_cpu_ids, cpu);
+
+		if (cpu < nr_cpu_ids && cpu_isset(cpu, andp))
+			return cpu;
+	}
+	return nr_cpu_ids;
 }
-EXPORT_SYMBOL(__next_cpu_nr);
-#endif
+EXPORT_SYMBOL(cpus_next_in);
 
-int __any_online_cpu(const cpumask_t *mask)
+int any_cpu_in(cpumask_t mask, cpumask_t andmask)
 {
 	int cpu;
 
-	for_each_cpu_mask(cpu, *mask) {
-		if (cpu_online(cpu))
+	for_each_cpu(cpu, mask) {
+		if (cpu_isset(cpu, andmask))
 			break;
 	}
 	return cpu;
 }
-EXPORT_SYMBOL(__any_online_cpu);
+EXPORT_SYMBOL(any_cpu_in);

Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected

[Rusty Russell]

On Wednesday 01 October 2008 02:46:59 Linus Torvalds wrote:
> Quite frankly, I personally do hate typedefs that end up being pointers,
> and used as pointers, without showing that in the source code.
...
> I'm now a bit more leery about this whole thing just
> because the typedef ends up hiding so much - it doesn't just hide the
> basic type, it hides a very basic *code* issue.

Yes, this is why my version of the rework moved away from typedefs, except for 
the special case of "cpumask_var_t" for stack vars where this trick is really 
desired.

Everywhere else, the code becomes nice and clear: struct cpumask *.

Cheers,
Rusty.

Re: [RFC 1/1] cpumask: New cpumask API - take 2 - use unsigned longs

[Rusty Russell]

On Wednesday 01 October 2008 08:22:09 Mike Travis wrote:
> Here's an alternate proposal for the new cpumask API.  I have not yet begun
...
> +/* cpumask_t defaults to pointer to constant bit map */
> +typedef const unsigned long *cpumask_t;

Hiding a const here is not a good idea either, I think :(

Rusty.

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (143 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (136 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (130 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (126 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (115 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (109 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (102 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (95 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of regressions introduced between 2.6.26 and 2.6.27.

The following bug entry is on the current list of known regressions
introduced between 2.6.26 and 2.6.27.  Please verify if it still should
be listed and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (87 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (66 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2 command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (59 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (53 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (44 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (38 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (31 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (17 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed and let me know
(either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (10 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4
Handled-By	: Peter Zijlstra <a.p.zijlstra@chello.nl>

[Bug #11215] INFO: possible recursive locking detected ps2_command

[Rafael J. Wysocki]

This message has been generated automatically as a part of a report
of recent regressions.

The following bug entry is on the current list of known regressions
from 2.6.26.  Please verify if it still should be listed
and let me know (either way).


Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=11215
Subject		: INFO: possible recursive locking detected ps2_command
Submitter	: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Date		: 2008-07-31 9:41 (3 days old)
References	: http://marc.info/?l=linux-kernel&m=121749737011637&w=4