* PROBLEM: PPP and other serial port related application hangs in kernel space
@ 2010-06-09 20:46 Ales Teska
2010-06-09 21:16 ` arnd
2010-06-14 14:38 ` Maciej Rutecki
0 siblings, 2 replies; 4+ messages in thread
From: Ales Teska @ 2010-06-09 20:46 UTC (permalink / raw)
To: linux-kernel
[-- Attachment #1: Type: text/plain, Size: 13296 bytes --]
Hi all,
after upgrade of Linux kernel to version 2.6.34 I started to observe following problem - ppp and other serial port related application occasionally (in 1 hour or 1/10 ppp connections) 'hangs' (see description bellow) rendering related serial device unusable. I backtracked this issue to 2.6.32.15.
Application remains in the condition marked as 'D' in 'ps' output (waiting for result from kernel space, if I understand that correctly); it stays in this condition forever.
Moreover any other application that tries to open same serial port hangs the same way.
Here is example of such a situation:
# ps ax
PID TTY STAT TIME COMMAND
....
1275 ? D 0:01 ufoprobe-client /dev/ttyUSB0
....
I also found following information in dmesg:
[ 1673.660876] ------------[ cut here ]------------
[ 1673.661471] WARNING: at drivers/char/tty_io.c:1278 tty_open+0x213/0x451()
[ 1673.662358] Modules linked in: ppp_deflate zlib_deflate bsd_comp ppp_async crc_ccitt ppp_generic slhc ipv6 nvram msr cpuid ledtrig_timer ledtrig_heartbeat ledtrig_default_on geodewdt lm90 hwmon scx200_acb option usbserial ehci_hcd ohci_hcd via_rhine usbcore leds_alix2 mii
[ 1673.689168] Pid: 1275, comm: ufoprobe_client Not tainted 2.6.34-486-exiprobes #1
[ 1673.690452] Call Trace:
[ 1673.690947] [<c10e93af>] ? tty_open+0x213/0x451
[ 1673.691926] [<c1018f51>] warn_slowpath_common+0x45/0x5c
[ 1673.693006] [<c1018f75>] warn_slowpath_null+0xd/0x10
[ 1673.694293] [<c10e93af>] tty_open+0x213/0x451
[ 1673.694755] [<c1068105>] chrdev_open+0xe3/0x126
[ 1673.695733] [<c10648e5>] __dentry_open+0x123/0x1f7
[ 1673.697472] [<c10655f8>] nameidata_to_filp+0x29/0x3d
[ 1673.697726] [<c1068022>] ? chrdev_open+0x0/0x126
[ 1673.698957] [<c106d961>] do_last+0x361/0x474
[ 1673.700138] [<c1066861>] ? percpu_counter_add+0x23/0x2f
[ 1673.701189] [<c106ed97>] do_filp_open+0x165/0x3b5
[ 1673.701700] [<c10212e8>] ? update_process_times+0x3a/0x3e
[ 1673.703295] [<c1075c1b>] ? spin_unlock+0x17/0x22
[ 1673.704537] [<c10646ac>] do_sys_open+0x4a/0xec
[ 1673.705244] [<c1064790>] sys_open+0x1e/0x26
[ 1673.706190] [<c118c835>] syscall_call+0x7/0xb
[ 1673.706644] [<c1180000>] ? xfrm_add_pol_expire+0x7a/0x166
[ 1673.708205] ---[ end trace 69d4cf5dc236c7af ]---
Keywords: ppp tty serial
Kernel version: Linux version 2.6.34-486-exiprobes (root@voyage) (gcc version 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)) #1 PREEMPT Wed Jun 9 19:18:19 GMT 2010
Environment:
ALIX2D2 Board with 2 LAN and 2 miniPCI, LX800, USB
LX-800 with integrated RAM and PSU
CPU: 500 MHz AMD Geode LX800
Dual USB port
DRAM: 256 MB DDR DRAM on board
Storage: CompactFlash socket
2 Ethernet channels (Via VT6105M 10/100)
I/O: DB9 serial port, dual USB port
# lspci
00:01.0 Host bridge: Advanced Micro Devices [AMD] Unknown device 2080 (rev 33)
00:01.2 Entertainment encryption device: Advanced Micro Devices [AMD] Geode LX AES Security Block
00:09.0 Ethernet controller: VIA Technologies, Inc. VT6105M [Rhine-III] (rev 96)
00:0b.0 Ethernet controller: VIA Technologies, Inc. VT6105M [Rhine-III] (rev 96)
00:0f.0 ISA bridge: Advanced Micro Devices [AMD] CS5536 [Geode companion] ISA (rev 03)
00:0f.2 IDE interface: Advanced Micro Devices [AMD] CS5536 [Geode companion] IDE (rev 01)
00:0f.4 USB Controller: Advanced Micro Devices [AMD] CS5536 [Geode companion] OHC (rev 02)
00:0f.5 USB Controller: Advanced Micro Devices [AMD] CS5536 [Geode companion] EHC (rev 02)
Processor information (from /proc/cpuinfo):
processor : 0
vendor_id : AuthenticAMD
cpu family : 5
model : 10
model name : Geode(TM) Integrated Processor by AMD PCS
stepping : 2
cpu MHz : 498.071
cache size : 128 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu de pse tsc msr cx8 sep pge cmov clflush mmx mmxext 3dnowext 3dnow
bogomips : 996.14
clflush size : 32
cache_alignment : 32
address sizes : 32 bits physical, 32 bits virtual
power management:
Module information (from /proc/modules):
ppp_deflate 2734 0 - Live 0xd0a65000
zlib_deflate 15675 1 ppp_deflate, Live 0xd0a58000
bsd_comp 3754 0 - Live 0xd0a3c000
ppp_async 5124 0 - Live 0xd0a31000
crc_ccitt 983 1 ppp_async, Live 0xd0a26000
ppp_generic 13543 3 ppp_deflate,bsd_comp,ppp_async, Live 0xd0a19000
slhc 3559 1 ppp_generic, Live 0xd0a0b000
ipv6 183015 14 - Live 0xd09c8000
nvram 4136 0 - Live 0xd0981000
msr 1494 0 - Live 0xd0976000
cpuid 1263 0 - Live 0xd096c000
ledtrig_timer 1496 0 - Live 0xd0962000
ledtrig_heartbeat 857 0 - Live 0xd0958000
ledtrig_default_on 512 0 - Live 0xd094f000
geodewdt 2091 2 - Live 0xd0946000
lm90 6492 0 - Live 0xd093b000
hwmon 1007 1 lm90, Live 0xd092f000
scx200_acb 2570 0 - Live 0xd0925000
option 13661 2 - Live 0xd0915000
usbserial 22562 7 option, Live 0xd08f9000
ehci_hcd 38670 0 - Live 0xd08cc000
ohci_hcd 27580 0 - Live 0xd08ad000
via_rhine 15098 0 - Live 0xd0889000
usbcore 112174 5 option,usbserial,ehci_hcd,ohci_hcd, Live 0xd0856000
leds_alix2 1315 0 - Live 0xd0825000
mii 2687 1 via_rhine, Live 0xd0804000
Loaded driver and hardware information (/proc/ioports, /proc/iomem)
0000-001f : dma1
0020-0021 : pic1
0040-0043 : timer0
0050-0053 : timer1
0060-0060 : keyboard
0064-0064 : keyboard
0070-0071 : rtc_cmos
0070-0071 : rtc0
0080-008f : dma page reg
00a0-00a1 : pic2
00c0-00df : dma2
00f0-00ff : fpu
0170-0177 : 0000:00:0f.2
01f0-01f7 : 0000:00:0f.2
01f0-01f7 : pata_cs5536
02f8-02ff : serial
0376-0376 : 0000:00:0f.2
03f6-03f6 : 0000:00:0f.2
03f6-03f6 : pata_cs5536
03f8-03ff : serial
0cf8-0cff : PCI conf1
1000-10ff : 0000:00:09.0
1000-10ff : via-rhine
1400-14ff : 0000:00:0b.0
1400-14ff : via-rhine
6000-6007 : 0000:00:0f.0
6000-6007 : CS5536 ACB0
6100-61ff : 0000:00:0f.0
6100-61ff : leds_alix2
6200-623f : 0000:00:0f.0
6200-623f : cs5535-mfgpt
9c00-9c3f : 0000:00:0f.0
9d00-9d7f : 0000:00:0f.0
ac1c-ac1f : 0000:00:01.0
ff00-ff0f : 0000:00:0f.2
ff00-ff0f : pata_cs5536
# cat /proc/iomem
00000000-00000fff : reserved
00001000-0009ffff : System RAM
000a0000-000bffff : Video RAM area
000e0000-000effff : Extension ROM
000f0000-000fffff : reserved
000f0000-000fffff : System ROM
00100000-0fffffff : System RAM
01000000-0118d4e5 : Kernel code
0118d4e6-0125dde7 : Kernel data
01282000-012d6bab : Kernel bss
e0000000-e00000ff : 0000:00:09.0
e0000000-e00000ff : via-rhine
e0040000-e00400ff : 0000:00:0b.0
e0040000-e00400ff : via-rhine
efff4000-efff7fff : 0000:00:01.2
efff4000-efff7fff : geode-aes
efffd000-efffdfff : 0000:00:0f.5
efffd000-efffdfff : ehci_hcd
efffe000-efffefff : 0000:00:0f.4
efffe000-efffefff : ohci_hcd
fff00000-ffffffff : reserved
PCI information ('lspci -vvv' as root)
# lspci -vvv
00:01.0 Host bridge: Advanced Micro Devices [AMD] Unknown device 2080 (rev 33)
Subsystem: Advanced Micro Devices [AMD] Unknown device 2080
Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
Status: Cap- 66MHz+ UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 248, Cache Line Size: 32 bytes
Region 0: I/O ports at ac1c [size=4]
00:01.2 Entertainment encryption device: Advanced Micro Devices [AMD] Geode LX AES Security Block
Subsystem: Advanced Micro Devices [AMD] Geode LX AES Security Block
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
Status: Cap- 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 0, Cache Line Size: 32 bytes
Interrupt: pin A routed to IRQ 9
Region 0: Memory at efff4000 (32-bit, non-prefetchable) [size=16K]
00:09.0 Ethernet controller: VIA Technologies, Inc. VT6105M [Rhine-III] (rev 96)
Subsystem: VIA Technologies, Inc. Unknown device 0106
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV+ VGASnoop- ParErr- Stepping+ SERR- FastB2B-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 64 (750ns min, 2000ns max), Cache Line Size: 32 bytes
Interrupt: pin A routed to IRQ 10
Region 0: I/O ports at 1000 [size=256]
Region 1: Memory at e0000000 (32-bit, non-prefetchable) [size=256]
Capabilities: [40] Power Management version 2
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
00:0b.0 Ethernet controller: VIA Technologies, Inc. VT6105M [Rhine-III] (rev 96)
Subsystem: VIA Technologies, Inc. Unknown device 0106
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV+ VGASnoop- ParErr- Stepping+ SERR- FastB2B-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 64 (750ns min, 2000ns max), Cache Line Size: 32 bytes
Interrupt: pin A routed to IRQ 15
Region 0: I/O ports at 1400 [size=256]
Region 1: Memory at e0040000 (32-bit, non-prefetchable) [size=256]
Capabilities: [40] Power Management version 2
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
00:0f.0 ISA bridge: Advanced Micro Devices [AMD] CS5536 [Geode companion] ISA (rev 03)
Subsystem: Advanced Micro Devices [AMD] CS5536 [Geode companion] ISA
Control: I/O+ Mem- BusMaster- SpecCycle+ MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
Status: Cap- 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Region 0: I/O ports at 6000 [size=8]
Region 1: I/O ports at 6100 [size=256]
Region 2: I/O ports at 6200 [size=64]
Region 3: I/O ports at <unassigned>
Region 4: I/O ports at 9d00 [size=128]
Region 5: I/O ports at 9c00 [size=64]
00:0f.2 IDE interface: Advanced Micro Devices [AMD] CS5536 [Geode companion] IDE (rev 01) (prog-if 80 [Master])
Subsystem: Advanced Micro Devices [AMD] CS5536 [Geode companion] IDE
Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
Status: Cap- 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 248, Cache Line Size: 32 bytes
Region 0: [virtual] Memory at 000001f0 (32-bit, non-prefetchable) [disabled] [size=8]
Region 1: [virtual] Memory at 000003f0 (type 3, non-prefetchable) [disabled] [size=1]
Region 2: [virtual] Memory at 00000170 (32-bit, non-prefetchable) [disabled] [size=8]
Region 3: [virtual] Memory at 00000370 (type 3, non-prefetchable) [disabled] [size=1]
Region 4: I/O ports at ff00 [size=16]
00:0f.4 USB Controller: Advanced Micro Devices [AMD] CS5536 [Geode companion] OHC (rev 02) (prog-if 10 [OHCI])
Subsystem: Advanced Micro Devices [AMD] CS5536 [Geode companion] OHC
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
Status: Cap+ 66MHz+ UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 0, Cache Line Size: 32 bytes
Interrupt: pin D routed to IRQ 12
Region 0: Memory at efffe000 (32-bit, non-prefetchable) [size=4K]
Capabilities: [40] Power Management version 2
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
00:0f.5 USB Controller: Advanced Micro Devices [AMD] CS5536 [Geode companion] EHC (rev 02) (prog-if 20 [EHCI])
Subsystem: Advanced Micro Devices [AMD] CS5536 [Geode companion] EHC
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
Status: Cap+ 66MHz+ UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 0, Cache Line Size: 32 bytes
Interrupt: pin D routed to IRQ 12
Region 0: Memory at efffd000 (32-bit, non-prefetchable) [size=4K]
Capabilities: [40] Power Management version 2
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
SCSI information (from /proc/scsi/scsi)
# cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
Vendor: ATA Model: IEI Technology C Rev: 0811
Type: Direct-Access ANSI SCSI revision: 05
Other information that might be relevant to the problem:
* Previous version of the kernel i used (2.6.29.1) was and still is OK (without this issue).
* I'm using ppp version 2.4.5
* My kernel is vanilla version compiled for i486
* So far I'm not able to write script to reproduce that for 100% - but just enabling and disabling ppp connection will do the work
Thank you,
Ales Teska
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: PROBLEM: PPP and other serial port related application hangs in kernel space
2010-06-09 20:46 PROBLEM: PPP and other serial port related application hangs in kernel space Ales Teska
@ 2010-06-09 21:16 ` arnd
2010-06-11 0:04 ` Ales Teska
2010-06-14 14:38 ` Maciej Rutecki
1 sibling, 1 reply; 4+ messages in thread
From: arnd @ 2010-06-09 21:16 UTC (permalink / raw)
To: Ales Teska; +Cc: linux-kernel, Greg KH, Alan Cox
On Wednesday 09 June 2010 22:46:28 Ales Teska wrote:
> after upgrade of Linux kernel to version 2.6.34 I started to observe following problem
> - ppp and other serial port related application occasionally (in 1 hour or 1/10 ppp
> connections) 'hangs' (see description bellow) rendering related serial device unusable.
> I backtracked this issue to 2.6.32.15.
> Application remains in the condition marked as 'D' in 'ps' output (waiting for result
> from kernel space, if I understand that correctly); it stays in this condition forever.
It would be good to find out where exactly the application hangs. Please try a sysrq-t
(press Alt+SysRq+t simultaneously) or cat /proc/<pid-that-hangs>/stack.
It might also be helpful to try running the kernel with CONFIG_LOCKDEP and/or
CONFIG_TTY_MUTEX enabled. For the latter one, you need to get the source
from the tty branch of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl.git
> I also found following information in dmesg:
> [ 1673.660876] ------------[ cut here ]------------
> [ 1673.661471] WARNING: at drivers/char/tty_io.c:1278 tty_open+0x213/0x451()
> [ 1673.662358] Modules linked in: ppp_deflate zlib_deflate bsd_comp ppp_async crc_ccitt ppp_generic slhc ipv6 nvram msr cpuid ledtrig_timer ledtrig_heartbeat ledtrig_default_on geodewdt lm90 hwmon scx200_acb option usbserial ehci_hcd ohci_hcd via_rhine usbcore leds_alix2 mii
> [ 1673.689168] Pid: 1275, comm: ufoprobe_client Not tainted 2.6.34-486-exiprobes #1
> [ 1673.690452] Call Trace:
> [ 1673.690947] [<c10e93af>] ? tty_open+0x213/0x451
> [ 1673.691926] [<c1018f51>] warn_slowpath_common+0x45/0x5c
> [ 1673.693006] [<c1018f75>] warn_slowpath_null+0xd/0x10
> [ 1673.694293] [<c10e93af>] tty_open+0x213/0x451
> [ 1673.694755] [<c1068105>] chrdev_open+0xe3/0x126
Do you always see this message exactly once before it hangs?
Arnd
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: PROBLEM: PPP and other serial port related application hangs in kernel space
2010-06-09 21:16 ` arnd
@ 2010-06-11 0:04 ` Ales Teska
0 siblings, 0 replies; 4+ messages in thread
From: Ales Teska @ 2010-06-11 0:04 UTC (permalink / raw)
To: arnd; +Cc: linux-kernel, Greg KH, Alan Cox
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Here is a stack from 2.6.34 with few debugging options on:
# cat /proc/1390/stack
[<c10f79fb>] tty_ldisc_ref_wait+0x5d/0x75
[<c10f3c54>] tty_ioctl+0x6d1/0x731
[<c1077e6c>] vfs_ioctl+0x22/0x86
[<c10783ba>] do_vfs_ioctl+0x45a/0x4a5
[<c1078431>] sys_ioctl+0x2c/0x45
[<c1198e65>] syscall_call+0x7/0xb
[<ffffffff>] 0xffffffff
[ 841.121579] INFO: task pppd:1390 blocked for more than 120 seconds.
[ 841.122613] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 841.123578] pppd D cec53ea4 0 1390 1139 0x00000000
[ 841.126502] cec53ebc 00000046 c1037b30 cec53ea4 c1198bf6 cec29070 cec291f8 cfdbc520
[ 841.134781] c10f7049 cec53ebc 00000000 cec51800 cec53ec4 cec53ee4 c10f79fb 00000000
[ 841.143007] cec29070 c102b471 c13dc904 c13dc904 d0c35211 cefc6aa0 cec51800 cec53f1c
[ 841.151250] Call Trace:
[ 841.151815] [<c1037b30>] ? trace_hardirqs_on+0xb/0xd
[ 841.152755] [<c1198bf6>] ? _raw_spin_unlock_irqrestore+0x53/0x60
[ 841.153657] [<c10f7049>] ? spin_unlock_irqrestore+0x8/0xa
[ 841.154601] [<c10f79fb>] tty_ldisc_ref_wait+0x5d/0x75
[ 841.155265] [<c102b471>] ? autoremove_wake_function+0x0/0x33
[ 841.156456] [<d0c35211>] ? serial_ioctl+0x0/0x68 [usbserial]
[ 841.157913] [<c10f3c54>] tty_ioctl+0x6d1/0x731
[ 841.158834] [<c102fa77>] ? sched_clock_cpu+0xac/0xbc
[ 841.159658] [<c10f3583>] ? tty_ioctl+0x0/0x731
[ 841.160922] [<c1077e6c>] vfs_ioctl+0x22/0x86
[ 841.161836] [<c10783ba>] do_vfs_ioctl+0x45a/0x4a5
[ 841.162746] [<c1036a5e>] ? put_lock_stats+0xd/0x21
[ 841.163699] [<c1036ac6>] ? lock_release_holdtime+0x54/0x5a
[ 841.164530] [<c100fd87>] ? do_page_fault+0x27c/0x285
[ 841.165898] [<c102e978>] ? up_read+0x16/0x28
[ 841.166820] [<c1078431>] sys_ioctl+0x2c/0x45
[ 841.167452] [<c1198e65>] syscall_call+0x7/0xb
[ 841.168403] no locks held by pppd/1390.
... strangely now I'm getting different message in the dmesg output (and actually +120 seconds from incident).
Ratio of hangs is now higher with this build ...
I will do a test with CONFIG_LOCKDEP & CONFIG_TTY_MUTEX options over the weekend.
Ales
On 9 Jun 2010, at 23:16 , arnd@arndb.de wrote:
> On Wednesday 09 June 2010 22:46:28 Ales Teska wrote:
>> after upgrade of Linux kernel to version 2.6.34 I started to observe following problem
>> - ppp and other serial port related application occasionally (in 1 hour or 1/10 ppp
>> connections) 'hangs' (see description bellow) rendering related serial device unusable.
>> I backtracked this issue to 2.6.32.15.
>> Application remains in the condition marked as 'D' in 'ps' output (waiting for result
>> from kernel space, if I understand that correctly); it stays in this condition forever.
>
> It would be good to find out where exactly the application hangs. Please try a sysrq-t
> (press Alt+SysRq+t simultaneously) or cat /proc/<pid-that-hangs>/stack.
>
> It might also be helpful to try running the kernel with CONFIG_LOCKDEP and/or
> CONFIG_TTY_MUTEX enabled. For the latter one, you need to get the source
> from the tty branch of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl.git
>
>> I also found following information in dmesg:
>> [ 1673.660876] ------------[ cut here ]------------
>> [ 1673.661471] WARNING: at drivers/char/tty_io.c:1278 tty_open+0x213/0x451()
>> [ 1673.662358] Modules linked in: ppp_deflate zlib_deflate bsd_comp ppp_async crc_ccitt ppp_generic slhc ipv6 nvram msr cpuid ledtrig_timer ledtrig_heartbeat ledtrig_default_on geodewdt lm90 hwmon scx200_acb option usbserial ehci_hcd ohci_hcd via_rhine usbcore leds_alix2 mii
>> [ 1673.689168] Pid: 1275, comm: ufoprobe_client Not tainted 2.6.34-486-exiprobes #1
>> [ 1673.690452] Call Trace:
>> [ 1673.690947] [<c10e93af>] ? tty_open+0x213/0x451
>> [ 1673.691926] [<c1018f51>] warn_slowpath_common+0x45/0x5c
>> [ 1673.693006] [<c1018f75>] warn_slowpath_null+0xd/0x10
>> [ 1673.694293] [<c10e93af>] tty_open+0x213/0x451
>> [ 1673.694755] [<c1068105>] chrdev_open+0xe3/0x126
>
> Do you always see this message exactly once before it hangs?
>
> Arnd
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: PROBLEM: PPP and other serial port related application hangs in kernel space
2010-06-09 20:46 PROBLEM: PPP and other serial port related application hangs in kernel space Ales Teska
2010-06-09 21:16 ` arnd
@ 2010-06-14 14:38 ` Maciej Rutecki
1 sibling, 0 replies; 4+ messages in thread
From: Maciej Rutecki @ 2010-06-14 14:38 UTC (permalink / raw)
To: Ales Teska; +Cc: linux-kernel
On środa, 9 czerwca 2010 o 22:46:28 Ales Teska wrote:
> Hi all,
>
> after upgrade of Linux kernel to version 2.6.34 I started to observe
> following problem - ppp and other serial port related application
> occasionally (in 1 hour or 1/10 ppp connections) 'hangs' (see description
> bellow) rendering related serial device unusable. I backtracked this issue
> to 2.6.32.15. Application remains in the condition marked as 'D' in 'ps'
> output (waiting for result from kernel space, if I understand that
> correctly); it stays in this condition forever. Moreover any other
> application that tries to open same serial port hangs the same way.
>
I created a Bugzilla entry at
https://bugzilla.kernel.org/show_bug.cgi?id=16206
for your bug report, please add your address to the CC list in there, thanks!
--
Maciej Rutecki
http://www.maciek.unixy.pl
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-- links below jump to the message on this page --
2010-06-09 20:46 PROBLEM: PPP and other serial port related application hangs in kernel space Ales Teska
2010-06-09 21:16 ` arnd
2010-06-11 0:04 ` Ales Teska
2010-06-14 14:38 ` Maciej Rutecki
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