Re: [PATCH] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

Re: [PATCH] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[Palmer Dabbelt]

I cut the RISC-V stuff, but I intend to reply to it later.  As you
said, it's just a different topic.

>>> However, I did see a lot of similar bugs now that you point me to it:
>>>
>>> $  grep -r \\\<CONFIG obj-tmp/usr/include/
>>> obj-tmp/usr/include/asm-generic/fcntl.h:#ifndef CONFIG_64BIT
>>> obj-tmp/usr/include/asm-generic/mman-common.h:#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED
>>> obj-tmp/usr/include/asm-generic/unistd.h:#ifdef CONFIG_MMU
>>> obj-tmp/usr/include/asm-generic/unistd.h:#endif /* CONFIG_MMU */
>>> obj-tmp/usr/include/linux/atmdev.h:#ifdef CONFIG_COMPAT
>>> obj-tmp/usr/include/linux/elfcore.h:#ifdef CONFIG_BINFMT_ELF_FDPIC
>>> obj-tmp/usr/include/linux/eventpoll.h:#ifdef CONFIG_PM_SLEEP
>>> obj-tmp/usr/include/linux/fb.h:#ifdef CONFIG_FB_BACKLIGHT
>>> obj-tmp/usr/include/linux/flat.h:#ifdef CONFIG_BINFMT_SHARED_FLAT
>>> obj-tmp/usr/include/linux/hw_breakpoint.h:#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
>>> obj-tmp/usr/include/linux/pktcdvd.h:#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
>>> obj-tmp/usr/include/linux/raw.h:#define MAX_RAW_MINORS CONFIG_MAX_RAW_DEVS
>>> obj-tmp/usr/include/asm/ptrace.h:#ifdef CONFIG_CPU_ENDIAN_BE8
>>>
>>> These all have the same problem, and we should fix them, as well as
>>> (probably) adding an automated check to scripts/headers_install.sh.
>>
>> Well, I was going to go fix them all and ran a very similar grep, but
>> I think I got a lot of false-positives.  If I understand correctly,
>> it's allowed to have CONFIG_* when guarded by __KERNEL__ in
>> user-visible headers?
>
> That is right.

It turns out there was actually a header checking script
(scripts/headers_check.pl), and it already had a check for this.  The
check was just disabled because there was "too much noise".  Rather
than putting it in headers_install I've just fixed that script.  I'm
definately lacking in perl powers, so I have no idea if what I've done
is sane.  Specifically: there's a global variable and a line over 80
characters, but since there's a bunch of other violations I figure
it's fine.

>> Now that I've written that, I realize it'd be pretty easy to just use
>> cpp to drop everything inside __KERNEL__ and then look for CONFIG_*.
>
> The lines quoted above are from the output of 'make headers_install',
> which already drops everything inside of __KERNEL__. A lot of them
> probably just need to add that #ifdef, or move the portion of the
> header file to the normal (non-uabi) file.
>
>> If you want, I can try to do that, fix what triggers the check, and
>> re-submit everything together?
>
> That would be great, yes.

OK.  I think this has turned into more of a RFC than a PATCH,
though...  I've just #ifdef'd things for now to reduce the diff size,
though I think it might be cleaner to move some of them to the
non-user headers (ep_take_care_of_epollwakeup(), USE_WCACHING,
MAX_RAW_MINORS).

I'm pretty far out of my depth here, so these should all be carefully
considered, but there's a few that scare me more ("struct
elf_prstatus", "enum by_type_idx", AT_VECTOR_SIZE_ARCH).  I think
there's only one actual bug here (MAP_UNINITIALIZED), the rest just
quiet the checking script.  Each patch has my rationale for what I
did.

Since this touches a whole lot of stuff, I've added a whole bunch of
CCs.

[PATCH 01/13] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[Palmer Dabbelt]

When working on the RISC-V port I noticed that F_SETLK64 was being
defined on our 64-bit platform, despite our port being so new that
we've only ever had the 64-bit file ops.  Since there's not compat
layer for these, this causes fcntl to bail out.

It turns out that one of the ways in with F_SETLK64 was being defined
(there's some more in glibc, but that's a whole different story... :))
is the result of CONFIG_64BIT showing up in this user-visible header.
<asm-generic/bitsperlong.h> confirms this isn't sane, so I replaced it
with a __BITS_PER_LONG check.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/fcntl.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
index e063effe0cc1..14a5c8237d84 100644
--- a/include/uapi/asm-generic/fcntl.h
+++ b/include/uapi/asm-generic/fcntl.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_GENERIC_FCNTL_H
 #define _ASM_GENERIC_FCNTL_H
 
+#include <asm/bitsperlong.h>
 #include <linux/types.h>
 
 /*
@@ -115,7 +116,7 @@
 #define F_GETSIG	11	/* for sockets. */
 #endif
 
-#ifndef CONFIG_64BIT
+#if (__BITS_PER_LONG == 32)
 #ifndef F_GETLK64
 #define F_GETLK64	12	/*  using 'struct flock64' */
 #define F_SETLK64	13
-- 
2.4.6

[PATCH 02/13] Always expose __SYSCALL(... fork ...)

[Palmer Dabbelt]

I think this change actually doesn't do anything: __NR_fork was still
being defined either way, and on my machine fork() in <unistd.h> comes
from libc.

That said, I don't think there's any way to determine this
automatically, so this at least quiets the checker.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/unistd.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index e016bd9b1a04..e027ef7aa01f 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -865,11 +865,11 @@ __SYSCALL(__NR_uselib, sys_uselib)
 __SYSCALL(__NR__sysctl, sys_sysctl)
 
 #define __NR_fork 1079
-#ifdef CONFIG_MMU
+#if !defined(__KERNEL__) || defined(CONFIG_MMU)
 __SYSCALL(__NR_fork, sys_fork)
 #else
 __SYSCALL(__NR_fork, sys_ni_syscall)
-#endif /* CONFIG_MMU */
+#endif /* !__KERNEL__ || CONFIG_MMU */
 
 #undef __NR_syscalls
 #define __NR_syscalls (__NR_fork+1)
-- 
2.4.6

[PATCH 03/13] Hide COMPAT_ATM_ADDPARTY behind #ifdef __KERNEL__

[Palmer Dabbelt]

This used to just be behind an #ifdef COMPAT_COMPAT, so most of
userspace wouldn't have seen the definition before.  This change just
makes the __KERNEL__ part explicit to quiet the header checker.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/atmdev.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/atmdev.h b/include/uapi/linux/atmdev.h
index 93e0ec008ca8..f8b6223165da 100644
--- a/include/uapi/linux/atmdev.h
+++ b/include/uapi/linux/atmdev.h
@@ -100,7 +100,7 @@ struct atm_dev_stats {
 					/* use backend to make new if */
 #define ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct atm_iobuf)
  					/* add party to p2mp call */
-#ifdef CONFIG_COMPAT
+#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 /* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
 #define COMPAT_ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct compat_atm_iobuf)
 #endif
-- 
2.4.6

[PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Palmer Dabbelt]

This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
userspace wouldn't actually ever see it.  While I could have kept
hiding it, the man pages seem to indicate that MAP_UNINITIALIZED
should be visible:

  mmap(2)
  MAP_UNINITIALIZED (since Linux 2.6.33)
    Don't clear anonymous pages.  This flag is intended to improve
    performance on embedded devices.  This flag is honored only if the
    kernel was configured with the CONFIG_MMAP_ALLOW_UNINITIALIZED
    option.  Because of the security implications, that option is
    normally enabled only on embedded devices (i.e., devices where one
    has complete control of the contents of user memory).

and since the only time it shows up in my /usr/include is in this
header I believe this should have been visible to userspace (as
non-zero, which wouldn't do anything when or'd into the flags) all
along.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/mman-common.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h
index ddc3b36f1046..e58d1911ecc6 100644
--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h
@@ -19,7 +19,7 @@
 #define MAP_TYPE	0x0f		/* Mask for type of mapping */
 #define MAP_FIXED	0x10		/* Interpret addr exactly */
 #define MAP_ANONYMOUS	0x20		/* don't use a file */
-#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED
+#if !defined(__KERNEL__) || defined(CONFIG_MMAP_ALLOW_UNINITIALIZED)
 # define MAP_UNINITIALIZED 0x4000000	/* For anonymous mmap, memory could be uninitialized */
 #else
 # define MAP_UNINITIALIZED 0x0		/* Don't support this flag */
-- 
2.4.6

[PATCH 05/13] Hide some of "struct elf_prstatus" behind #ifdef __KERNEL__

[Palmer Dabbelt]

This one scares me: while I can't find any system calls that directly
take this as an argument, a comment in <linux/ptrace.h>

  "
   Generic ptrace interface that exports the architecture specific
   regsets using the corresponding NT_* types (which are also used in
   the core dump).  Please note that the NT_PRSTATUS note type in a
   core dump contains a full 'struct elf_prstatus'. But the
   user_regset for NT_PRSTATUS contains just the elf_gregset_t that is
   the pr_reg field of 'struct elf_prstatus'. For all the other
   user_regset flavors, the user_regset layout and the ELF core dump
   note payload are exactly the same layout.
  "

seems to indicate that it's possible to see this sometimes.  Since
this would only be visible to userspace in a somewhat convoluted
manner, I'm going to try and keep it as it was.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/elfcore.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/elfcore.h b/include/uapi/linux/elfcore.h
index 569737cfb557..f9320b588937 100644
--- a/include/uapi/linux/elfcore.h
+++ b/include/uapi/linux/elfcore.h
@@ -60,7 +60,7 @@ struct elf_prstatus
 	long	pr_instr;		/* Current instruction */
 #endif
 	elf_gregset_t pr_reg;	/* GP registers */
-#ifdef CONFIG_BINFMT_ELF_FDPIC
+#if defined(__KERNEL__) && defined(CONFIG_BINFMT_ELF_FDPIC)
 	/* When using FDPIC, the loadmap addresses need to be communicated
 	 * to GDB in order for GDB to do the necessary relocations.  The
 	 * fields (below) used to communicate this information are placed
-- 
2.4.6

[PATCH 06/13] Hide ep_take_care_of_epollwakeup() behind #ifdef __KERNEL__

[Palmer Dabbelt]

This doesn't make any sense to expose to userspace.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/eventpoll.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/uapi/linux/eventpoll.h b/include/uapi/linux/eventpoll.h
index bc81fb2e1f0e..290426bfb0aa 100644
--- a/include/uapi/linux/eventpoll.h
+++ b/include/uapi/linux/eventpoll.h
@@ -61,6 +61,7 @@ struct epoll_event {
 	__u64 data;
 } EPOLL_PACKED;
 
+#ifdef __KERNEL__
 #ifdef CONFIG_PM_SLEEP
 static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
 {
@@ -73,4 +74,6 @@ static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
 	epev->events &= ~EPOLLWAKEUP;
 }
 #endif
+#endif /*__KERNEL__*/
+
 #endif /* _UAPI_LINUX_EVENTPOLL_H */
-- 
2.4.6

[PATCH 07/13] Make FB_BACKLIGHT_{LEVELS,MAX} always visible

[Palmer Dabbelt]

Nothing else in the kernel defines this, and this header is visible to
userspace.  Rather than hiding it in an #ifdef, I think it's sane to
just make this visible to userspace.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/fb.h | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/include/uapi/linux/fb.h b/include/uapi/linux/fb.h
index fb795c3b3c17..8926f13bc19f 100644
--- a/include/uapi/linux/fb.h
+++ b/include/uapi/linux/fb.h
@@ -392,11 +392,8 @@ struct fb_cursor {
 	struct fb_image	image;	/* Cursor image */
 };
 
-#ifdef CONFIG_FB_BACKLIGHT
 /* Settings for the generic backlight code */
 #define FB_BACKLIGHT_LEVELS	128
 #define FB_BACKLIGHT_MAX	0xFF
-#endif
-
 
 #endif /* _UAPI_LINUX_FB_H */
-- 
2.4.6

[PATCH 08/13] Hide MAX_SHARED_LIBS behind #ifdef __KERNEL__

[Palmer Dabbelt]

I'm not sure what this is, but it doesn't feel like something that
should be exposed to userspace here.  I'm assuming this file was
exposed for the structure in it, which doesn't depend on
MAX_SHARED_LIBS.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/flat.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/uapi/linux/flat.h b/include/uapi/linux/flat.h
index 88cd6baba8f3..4ed679f3591e 100644
--- a/include/uapi/linux/flat.h
+++ b/include/uapi/linux/flat.h
@@ -13,11 +13,13 @@
 
 #define	FLAT_VERSION			0x00000004L
 
+#ifdef __KERNEL__
 #ifdef CONFIG_BINFMT_SHARED_FLAT
 #define	MAX_SHARED_LIBS			(4)
 #else
 #define	MAX_SHARED_LIBS			(1)
 #endif
+#endif /*__KERNEL__*/
 
 /*
  * To make everything easier to port and manage cross platform
-- 
2.4.6

[PATCH 09/13] Hide bp_type_idx behind #ifdef __KERNEL__

[Palmer Dabbelt]

I'm actually not sure what to do here: if this enum is meant to be
used by userspace, then it has to be the same regardless of kernel
configuration.  One option would be to have the kernel expose all the
values to userspace and then map them internally if
CONFIG_HAVE_MIXED_BREAKPOINT_REGS isn't set, but that feels like it'd
be more invasive.

Here I took the simple and fail-fast route to hide all the
definitions.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/hw_breakpoint.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
index b04000a2296a..2498bfbf56c4 100644
--- a/include/uapi/linux/hw_breakpoint.h
+++ b/include/uapi/linux/hw_breakpoint.h
@@ -17,14 +17,16 @@ enum {
 	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
 };
 
+#ifdef __KERNEL__
 enum bp_type_idx {
 	TYPE_INST 	= 0,
-#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
+#if defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
 	TYPE_DATA	= 0,
 #else
 	TYPE_DATA	= 1,
 #endif
 	TYPE_MAX
 };
+#endif /* __KERNEL__ */
 
 #endif /* _UAPI_LINUX_HW_BREAKPOINT_H */
-- 
2.4.6

[PATCH 10/13] Hide USE_WCACHING behind #ifdef __KERNEL__

[Palmer Dabbelt]

I don't think this was ever intended to be exposed to userspace.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/pktcdvd.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/uapi/linux/pktcdvd.h b/include/uapi/linux/pktcdvd.h
index 2640b9d4e243..e2a49bfee74e 100644
--- a/include/uapi/linux/pktcdvd.h
+++ b/include/uapi/linux/pktcdvd.h
@@ -33,11 +33,13 @@
  * able to successfully recover with this option (drive will return good
  * status as soon as the cdb is validated).
  */
+#ifdef __KERNEL__
 #if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
 #define USE_WCACHING		1
 #else
 #define USE_WCACHING		0
 #endif
+#endif /* __KERNEL__ */
 
 /*
  * No user-servicable parts beyond this point ->
-- 
2.4.6

[PATCH 11/13] Hide MAX_RAW_MINORS behind #ifdef __KERNEL__

[Palmer Dabbelt]

I don't think this was ever meant to be exposed to userspace.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/raw.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/uapi/linux/raw.h b/include/uapi/linux/raw.h
index 62d543e70603..6d8d87524ff2 100644
--- a/include/uapi/linux/raw.h
+++ b/include/uapi/linux/raw.h
@@ -13,6 +13,8 @@ struct raw_config_request
 	__u64	block_minor;
 };
 
+#ifdef __KERNEL__
 #define MAX_RAW_MINORS CONFIG_MAX_RAW_DEVS
+#endif
 
 #endif /* __LINUX_RAW_H */
-- 
2.4.6

[PATCH 12/13] Hide AT_VECTOR_SIZE_ARCH behind #ifdef __KERNEL__

[Palmer Dabbelt]

I think this actually isn't a good idea, but I can't find anything
outside of the kernel that's using this so I'm going to hide it.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 arch/x86/include/uapi/asm/auxvec.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/include/uapi/asm/auxvec.h b/arch/x86/include/uapi/asm/auxvec.h
index 77203ac352de..88e5fa6d97e7 100644
--- a/arch/x86/include/uapi/asm/auxvec.h
+++ b/arch/x86/include/uapi/asm/auxvec.h
@@ -9,11 +9,13 @@
 #endif
 #define AT_SYSINFO_EHDR		33
 
+#ifdef __KERNEL__
 /* entries in ARCH_DLINFO: */
 #if defined(CONFIG_IA32_EMULATION) || !defined(CONFIG_X86_64)
 # define AT_VECTOR_SIZE_ARCH 2
 #else /* else it's non-compat x86-64 */
 # define AT_VECTOR_SIZE_ARCH 1
 #endif
+#endif /* __KERNEL__ */
 
 #endif /* _ASM_X86_AUXVEC_H */
-- 
2.4.6

[PATCH 13/13] Re-enable and clean up "check_config()" in headers_check.pl

[Palmer Dabbelt]

I recently got bit by a CONFIG_ in userspace bug.  This has apparently
happened before, but the check got disabled for triggering too much.
In order to reduce false positives, I added some hueristics to avoid
detecting comments.

Since these tests all pass, I've now re-enabled them.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 scripts/headers_check.pl | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/scripts/headers_check.pl b/scripts/headers_check.pl
index 62320f93e903..dd413ad9c850 100755
--- a/scripts/headers_check.pl
+++ b/scripts/headers_check.pl
@@ -40,7 +40,7 @@ foreach my $file (@files) {
 		&check_asm_types();
 		&check_sizetypes();
 		&check_declarations();
-		# Dropped for now. Too much noise &check_config();
+		&check_config();
 	}
 	close $fh;
 }
@@ -76,9 +76,24 @@ sub check_declarations
 	}
 }
 
+my $check_config_in_multiline_comment = 0;
 sub check_config
 {
-	if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
+	my $nocomments = $line;
+	$nocomments =~ s/\/\*.*\*\///; # Remove ANSI-style comments (/* to */)
+	$nocomments =~ s/\/\/.*//;     # Remove C99-style comments (// to EOL)
+
+	# Check to see if we're within a multiline comment, and if so
+	# just remove the whole line.  I tried matching on '^ * ', but
+	# there's one header that doesn't prepend multi-line comments
+	# with * so that won't work.
+	if ($nocomments =~ m/\/\*/) { $check_config_in_multiline_comment = 1; }
+	if ($nocomments =~ m/\*\//) { $check_config_in_multiline_comment = 0; }
+	if ($check_config_in_multiline_comment == 1) { $nocomments = "" }
+
+	# Check to see if there is something that looks like CONFIG_
+	# inside a userspace-accessible header file and if so, print that out.
+	if ($nocomments =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
 		printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n";
 	}
 }
-- 
2.4.6

Re: [PATCH 09/13] Hide bp_type_idx behind #ifdef __KERNEL__

[David Howells]

Palmer Dabbelt <palmer@dabbelt.com> wrote:

> +#ifdef __KERNEL__
>  enum bp_type_idx {
>  	TYPE_INST 	= 0,
> -#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
> +#if defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
>  	TYPE_DATA	= 0,
>  #else
>  	TYPE_DATA	= 1,
>  #endif
>  	TYPE_MAX
>  };
> +#endif /* __KERNEL__ */

This should be in include/linux/hw_breakpoint.h without __KERNEL__ markings.

David

Re: [PATCH 10/13] Hide USE_WCACHING behind #ifdef __KERNEL__

[David Howells]

Palmer Dabbelt <palmer@dabbelt.com> wrote:

> I don't think this was ever intended to be exposed to userspace.

Then it should be in include/linux/pktcdvd.h

David

Re: [PATCH 11/13] Hide MAX_RAW_MINORS behind #ifdef __KERNEL__

[David Howells]

Palmer Dabbelt <palmer@dabbelt.com> wrote:

> I don't think this was ever meant to be exposed to userspace.

Then it should be in include/linux/raw.h

David

Re: [PATCH 12/13] Hide AT_VECTOR_SIZE_ARCH behind #ifdef __KERNEL__

[David Howells]

Palmer Dabbelt <palmer@dabbelt.com> wrote:

> I think this actually isn't a good idea, but I can't find anything
> outside of the kernel that's using this so I'm going to hide it.

It should be in arch/x86/include/asm/auxvec.h then.

Re: [PATCH] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[David Howells]

Rather than iterating through all the rest of your patches and saying the same
thing, if there's something in a UAPI header that needs wrapping in __KERNEL__
to exclude it from userspace's use, then it should be transferred to the
non-UAPI variant of that header (which should #include the UAPI variant).

David

Re: [PATCH] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[David Howells]

David Howells <dhowells@redhat.com> wrote:

> Rather than iterating through all the rest of your patches and saying the same
> thing, if there's something in a UAPI header that needs wrapping in __KERNEL__
> to exclude it from userspace's use, then it should be transferred to the
> non-UAPI variant of that header (which should #include the UAPI variant).

I should mention that there is the odd case where this is difficult to
achieve.  See include/uapi/linux/acct.h for an example...

David

Re: [PATCH] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[Palmer Dabbelt]

On Thu, 10 Sep 2015 04:18:05 PDT (-0700), dhowells@redhat.com wrote:
> David Howells <dhowells@redhat.com> wrote:
>
>> Rather than iterating through all the rest of your patches and saying the same
>> thing, if there's something in a UAPI header that needs wrapping in __KERNEL__
>> to exclude it from userspace's use, then it should be transferred to the
>> non-UAPI variant of that header (which should #include the UAPI variant).
>
> I should mention that there is the odd case where this is difficult to
> achieve.  See include/uapi/linux/acct.h for an example...

OK, sorry about that.  I'm submitting a v3 that should fix these
problems.

[PATCH v3] Remove #ifdef CONFIG_* from all userspace headers

[Palmer Dabbelt]

This patch set used to be called "[PATCH] Remove #ifdef CONFIG_64BIT
from all asm-generic/fcntl.h".

This is version 3 of the patch set.  I think things are kind of
cleaning up, but there's still some questions I have:

 * #4 might be dangerous, but I think this is the best way to do it
   because otherwise arch maintainers will have to #define this to
   something.  Since Xtensa already had exactly the same bug as the
   asm-generic header did, I think it'd be best to avoid those if
   possible.

   I'm OK changing this to define the value to 0 by default (though
   thinking now, I think it'd be better to not define it by default),
   since most kernels aren't going to have MAP_UNINITIALIZED do
   anything anyway.

 * #5 is big and I don't really understand what's going on, so it's
   probably broken somewhere.

Also, there's some checkpatch warnings that I purposely haven't fixed:

 * In #5, there's a checkpatch.pl complaint about same-line struct
   braces.  I've left that in to match the rest of the file, but I can
   also fix all of them if that would be better.

 * In #10, there's a checkpatch.pl complaint about a split printk
   format string, but that was there before and I don't see a way to
   make it a lot cleaner, so I'm leaving it alone.

 * In #13, there's two checkpatch.pl complains.  One is about block
   comments that is bogus, and one is about long lines but there's
   more of those so I think it's OK.

Thanks to everyone who looked at v2!




Changes since v2 (<1441832902-28993-1-git-send-email-palmer@dabbelt.com>)

* Patch set renamed.

* #2 is rewritten to use sys_ni.c instead of an #ifdef

* #3, #6, #8, #9, #10, and #11 no longer use "#ifdef __KERNEL__" but
   have instead moved the offending lines to the correct, kernel-only
   files.

* #4 has been rewritten to always define MAP_UNINITIALIZED to
   non-zero, rather than defining it to zero when in userspace.

* #5 got a whole lot longer -- rather than just always hiding these
   fields from userspace, there is now a second "struct
   elf_fdpic_prstatus" structure.  This should allow userspace to
   parse core dumps correctly.

* Rebased onto 9c488de24f7264f08d341024bffdd637b4d04c96.

Changes since v1 (<1441152610-22566-1-git-send-email-palmer@dabbelt.com>)

* All patches but #1 were added.

[PATCH 01/13] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[Palmer Dabbelt]

When working on the RISC-V port I noticed that F_SETLK64 was being
defined on our 64-bit platform, despite our port being so new that
we've only ever had the 64-bit file ops.  Since there's not compat
layer for these, this causes fcntl to bail out.

It turns out that one of the ways in with F_SETLK64 was being defined
(there's some more in glibc, but that's a whole different story... :))
is the result of CONFIG_64BIT showing up in this user-visible header.
<asm-generic/bitsperlong.h> confirms this isn't sane, so I replaced it
with a __BITS_PER_LONG check.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/fcntl.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
index e063effe0cc1..14a5c8237d84 100644
--- a/include/uapi/asm-generic/fcntl.h
+++ b/include/uapi/asm-generic/fcntl.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_GENERIC_FCNTL_H
 #define _ASM_GENERIC_FCNTL_H
 
+#include <asm/bitsperlong.h>
 #include <linux/types.h>
 
 /*
@@ -115,7 +116,7 @@
 #define F_GETSIG	11	/* for sockets. */
 #endif
 
-#ifndef CONFIG_64BIT
+#if (__BITS_PER_LONG == 32)
 #ifndef F_GETLK64
 #define F_GETLK64	12	/*  using 'struct flock64' */
 #define F_SETLK64	13
-- 
2.4.6

[PATCH 02/13] Use sys_ni.c instead of #ifdef to disable fork on CONFIG_NOMMU

[Palmer Dabbelt]

I think this change actually doesn't do anything: __NR_fork was still
being defined either way, and on my machine fork() in <unistd.h> comes
from libc.

This just moves to the standard mechanism for defining syscalls that
aren't implemented instead, which has the side-effect of no longer
having an #ifdef CONFIG_* in a user-visible header.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/unistd.h | 4 ----
 kernel/sys_ni.c                   | 1 +
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 8da542a2874d..21689284360b 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -867,11 +867,7 @@ __SYSCALL(__NR_uselib, sys_uselib)
 __SYSCALL(__NR__sysctl, sys_sysctl)
 
 #define __NR_fork 1079
-#ifdef CONFIG_MMU
 __SYSCALL(__NR_fork, sys_fork)
-#else
-__SYSCALL(__NR_fork, sys_ni_syscall)
-#endif /* CONFIG_MMU */
 
 #undef __NR_syscalls
 #define __NR_syscalls (__NR_fork+1)
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index a02decf15583..c830f7f9e36d 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -174,6 +174,7 @@ cond_syscall(sys_setfsuid);
 cond_syscall(sys_setfsgid);
 cond_syscall(sys_capget);
 cond_syscall(sys_capset);
+cond_syscall(sys_fork);
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read);
-- 
2.4.6

[PATCH 03/13] Move COMPAT_ATM_ADDPARTY to net/atm/svc.c

[Palmer Dabbelt]

This used to be behind an #ifdef COMPAT_COMPAT, so most of userspace
wouldn't have seen the definition before.  Unfortunately this header
file became visible to userspace, so the definition has instead been
moved to net/atm/svc.c (the only user).

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/atmdev.h | 4 ----
 net/atm/svc.c               | 5 +++++
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/atmdev.h b/include/uapi/linux/atmdev.h
index 93e0ec008ca8..3dcec701501c 100644
--- a/include/uapi/linux/atmdev.h
+++ b/include/uapi/linux/atmdev.h
@@ -100,10 +100,6 @@ struct atm_dev_stats {
 					/* use backend to make new if */
 #define ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct atm_iobuf)
  					/* add party to p2mp call */
-#ifdef CONFIG_COMPAT
-/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
-#define COMPAT_ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct compat_atm_iobuf)
-#endif
 #define ATM_DROPPARTY 	_IOW('a', ATMIOC_SPECIAL+5,int)
 					/* drop party from p2mp call */
 
diff --git a/net/atm/svc.c b/net/atm/svc.c
index 3fa0a9ee98d1..9e2e6ef285e8 100644
--- a/net/atm/svc.c
+++ b/net/atm/svc.c
@@ -27,6 +27,11 @@
 #include "signaling.h"
 #include "addr.h"
 
+#ifdef CONFIG_COMPAT
+/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
+#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4, struct compat_atm_iobuf)
+#endif
+
 static int svc_create(struct net *net, struct socket *sock, int protocol,
 		      int kern);
 
-- 
2.4.6

[PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Palmer Dabbelt]

This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
userspace wouldn't actually ever see it be non-zero.  While I could
have kept hiding it, the man pages seem to indicate that
MAP_UNINITIALIZED should be visible:

  mmap(2)
  MAP_UNINITIALIZED (since Linux 2.6.33)
    Don't clear anonymous pages.  This flag is intended to improve
    performance on embedded devices.  This flag is honored only if the
    kernel was configured with the CONFIG_MMAP_ALLOW_UNINITIALIZED
    option.  Because of the security implications, that option is
    normally enabled only on embedded devices (i.e., devices where one
    has complete control of the contents of user memory).

and since the only time it shows up in my /usr/include is in this
header I believe this should have been visible to userspace (as
non-zero, which wouldn't do anything when or'd into the flags) all
along.

This change also applies to the xtensa version of this definition,
whic is the same as the generic one.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 arch/xtensa/include/uapi/asm/mman.h    | 4 +---
 include/uapi/asm-generic/mman-common.h | 4 +---
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h
index 201aec0e0446..2cbc1e717082 100644
--- a/arch/xtensa/include/uapi/asm/mman.h
+++ b/arch/xtensa/include/uapi/asm/mman.h
@@ -55,11 +55,9 @@
 #define MAP_NONBLOCK	0x20000		/* do not block on IO */
 #define MAP_STACK	0x40000		/* give out an address that is best suited for process/thread stacks */
 #define MAP_HUGETLB	0x80000		/* create a huge page mapping */
-#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED
+#ifndef MAP_UNINITIALIZED
 # define MAP_UNINITIALIZED 0x4000000	/* For anonymous mmap, memory could be
 					 * uninitialized */
-#else
-# define MAP_UNINITIALIZED 0x0		/* Don't support this flag */
 #endif
 
 /*
diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h
index ddc3b36f1046..7aeeb12db193 100644
--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h
@@ -19,10 +19,8 @@
 #define MAP_TYPE	0x0f		/* Mask for type of mapping */
 #define MAP_FIXED	0x10		/* Interpret addr exactly */
 #define MAP_ANONYMOUS	0x20		/* don't use a file */
-#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED
+#ifndef MAP_UNINITIALIZED
 # define MAP_UNINITIALIZED 0x4000000	/* For anonymous mmap, memory could be uninitialized */
-#else
-# define MAP_UNINITIALIZED 0x0		/* Don't support this flag */
 #endif
 
 #define MS_ASYNC	1		/* sync memory asynchronously */
-- 
2.4.6

[PATCH 05/13] Split FDPIC "struct elf_prstatus" to "struct elf_fdpic_prstatus"

[Palmer Dabbelt]

This is a pretty big change that I haven't tested any, which worries
me a lot.  The general idea here is that "struct elf_prstatus" can be
visible to userspace (from <linux/ptrace.h>)

  "
   Generic ptrace interface that exports the architecture specific
   regsets using the corresponding NT_* types (which are also used in
   the core dump).  Please note that the NT_PRSTATUS note type in a
   core dump contains a full 'struct elf_prstatus'. But the
   user_regset for NT_PRSTATUS contains just the elf_gregset_t that is
   the pr_reg field of 'struct elf_prstatus'. For all the other
   user_regset flavors, the user_regset layout and the ELF core dump
   note payload are exactly the same layout.
  "

so it shouldn't have an "#ifdef CONFIG_" in there.

This splits the structure into two different structures, one still
named "struct elf_prstatus", and one for ELF FDPIC that is named
"struct elf_fdpic_prstatus" -- the idea here is that most users are
standard ELF, so that's the name that didn't change.

I tried to fix all the users of "struct elf_prstatus" that should now
be using "struct elf_fdpic_prstatus".  The only testing I did here was
to build a Blackfin defconfig with "struct elf_prstatus" not defined,
and to build an x86 defconfig with "struct elf_fdpic_prstatus" not
defined.

Note that this fails checkpatch.pl with a complaint about wanting open
braces on the same line as struct definitions.  The existing struct
definitions in this file have the brace a line afterwards, so I'm
going to leave this alone.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/binfmt_elf_fdpic.c        |  6 +++---
 fs/proc/kcore.c              | 16 ++++++++++++++++
 include/linux/kexec.h        |  4 ++++
 include/uapi/linux/elfcore.h | 37 +++++++++++++++++++++++++++++++++++--
 kernel/kexec_core.c          |  4 ++++
 5 files changed, 62 insertions(+), 5 deletions(-)

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index d3634bfb7fe1..587bf0466d71 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1323,7 +1323,7 @@ static inline void fill_note(struct memelfnote *note, const char *name, int type
  * fill up all the fields in prstatus from the given task struct, except
  * registers which need to be filled up separately.
  */
-static void fill_prstatus(struct elf_prstatus *prstatus,
+static void fill_prstatus(struct elf_fdpic_prstatus *prstatus,
 			  struct task_struct *p, long signr)
 {
 	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
@@ -1406,7 +1406,7 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
 struct elf_thread_status
 {
 	struct list_head list;
-	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
+	struct elf_fdpic_prstatus prstatus;	/* NT_PRSTATUS */
 	elf_fpregset_t fpu;		/* NT_PRFPREG */
 	struct task_struct *thread;
 #ifdef ELF_CORE_COPY_XFPREGS
@@ -1539,7 +1539,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 	loff_t offset = 0, dataoff;
 	int numnote;
 	struct memelfnote *notes = NULL;
-	struct elf_prstatus *prstatus = NULL;	/* NT_PRSTATUS */
+	struct elf_fdpic_prstatus *prstatus = NULL;	/* NT_PRSTATUS */
 	struct elf_prpsinfo *psinfo = NULL;	/* NT_PRPSINFO */
  	LIST_HEAD(thread_list);
  	struct list_head *t;
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 92e6726f6e37..b1edd77ec854 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -90,7 +90,11 @@ static size_t get_kcore_size(int *nphdr, size_t *elf_buflen)
 			(*nphdr + 2)*sizeof(struct elf_phdr) + 
 			3 * ((sizeof(struct elf_note)) +
 			     roundup(sizeof(CORE_STR), 4)) +
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+			roundup(sizeof(struct elf_fdpic_prstatus), 4) +
+#else
 			roundup(sizeof(struct elf_prstatus), 4) +
+#endif
 			roundup(sizeof(struct elf_prpsinfo), 4) +
 			roundup(arch_task_struct_size, 4);
 	*elf_buflen = PAGE_ALIGN(*elf_buflen);
@@ -318,7 +322,11 @@ static char *storenote(struct memelfnote *men, char *bufp)
  */
 static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff)
 {
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	struct elf_fdpic_prstatus prstatus;	/* NT_PRSTATUS */
+#else
 	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
+#endif
 	struct elf_prpsinfo prpsinfo;	/* NT_PRPSINFO */
 	struct elf_phdr *nhdr, *phdr;
 	struct elfhdr *elf;
@@ -387,10 +395,18 @@ static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff)
 	/* set up the process status */
 	notes[0].name = CORE_STR;
 	notes[0].type = NT_PRSTATUS;
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	notes[0].datasz = sizeof(struct elf_fdpic_prstatus);
+#else
 	notes[0].datasz = sizeof(struct elf_prstatus);
+#endif
 	notes[0].data = &prstatus;
 
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	memset(&prstatus, 0, sizeof(struct elf_fdpic_prstatus));
+#else
 	memset(&prstatus, 0, sizeof(struct elf_prstatus));
+#endif
 
 	nhdr->p_filesz	= notesize(&notes[0]);
 	bufp = storenote(&notes[0], bufp);
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index d140b1e9faa7..d9196ccd3781 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -63,7 +63,11 @@
 #define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
 #define KEXEC_CORE_NOTE_NAME "CORE"
 #define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+#define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_fdpic_prstatus), 4)
+#else
 #define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
+#endif
 /*
  * The per-cpu notes area is a list of notes terminated by a "NULL"
  * note header.  For kdump, the code in vmcore.c runs in the context
diff --git a/include/uapi/linux/elfcore.h b/include/uapi/linux/elfcore.h
index 569737cfb557..697c52db0227 100644
--- a/include/uapi/linux/elfcore.h
+++ b/include/uapi/linux/elfcore.h
@@ -60,7 +60,40 @@ struct elf_prstatus
 	long	pr_instr;		/* Current instruction */
 #endif
 	elf_gregset_t pr_reg;	/* GP registers */
-#ifdef CONFIG_BINFMT_ELF_FDPIC
+	int pr_fpvalid;		/* True if math co-processor being used.  */
+};
+
+/* Architectures that set CONFIG_BINFMT_ELF_FDPIC use this instead of
+ * "struct elf_prstatus".
+ */
+struct elf_fdpic_prstatus
+{
+#if 0
+	long	pr_flags;	/* XXX Process flags */
+	short	pr_why;		/* XXX Reason for process halt */
+	short	pr_what;	/* XXX More detailed reason */
+#endif
+	struct elf_siginfo pr_info;	/* Info associated with signal */
+	short	pr_cursig;		/* Current signal */
+	unsigned long pr_sigpend;	/* Set of pending signals */
+	unsigned long pr_sighold;	/* Set of held signals */
+#if 0
+	struct sigaltstack pr_altstack;	/* Alternate stack info */
+	struct sigaction pr_action;	/* Signal action for current sig */
+#endif
+	pid_t	pr_pid;
+	pid_t	pr_ppid;
+	pid_t	pr_pgrp;
+	pid_t	pr_sid;
+	struct timeval pr_utime;	/* User time */
+	struct timeval pr_stime;	/* System time */
+	struct timeval pr_cutime;	/* Cumulative user time */
+	struct timeval pr_cstime;	/* Cumulative system time */
+#if 0
+	long	pr_instr;		/* Current instruction */
+#endif
+	elf_gregset_t pr_reg;	/* GP registers */
+
 	/* When using FDPIC, the loadmap addresses need to be communicated
 	 * to GDB in order for GDB to do the necessary relocations.  The
 	 * fields (below) used to communicate this information are placed
@@ -69,7 +102,7 @@ struct elf_prstatus
 	 */
 	unsigned long pr_exec_fdpic_loadmap;
 	unsigned long pr_interp_fdpic_loadmap;
-#endif
+
 	int pr_fpvalid;		/* True if math co-processor being used.  */
 };
 
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 201b45327804..8d2fc707fecf 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -977,7 +977,11 @@ static void final_note(u32 *buf)
 
 void crash_save_cpu(struct pt_regs *regs, int cpu)
 {
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	struct elf_fdpic_prstatus prstatus;
+#else
 	struct elf_prstatus prstatus;
+#endif
 	u32 *buf;
 
 	if ((cpu < 0) || (cpu >= nr_cpu_ids))
-- 
2.4.6

[PATCH 06/13] Move ep_take_care_of_epollwakeup() to fs/eventpoll.c

[Palmer Dabbelt]

This doesn't make any sense to expose to userspace, so it's been moved
to the one user.  This was introduced by commit 95f19f658ce1 ("epoll:
drop EPOLLWAKEUP if PM_SLEEP is disabled").

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/eventpoll.c                 | 13 +++++++++++++
 include/uapi/linux/eventpoll.h | 12 ------------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 1e009cad8d5c..aadee3d1931a 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1812,6 +1812,19 @@ SYSCALL_DEFINE1(epoll_create, int, size)
 	return sys_epoll_create1(0);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
+		epev->events &= ~EPOLLWAKEUP;
+}
+#else
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	epev->events &= ~EPOLLWAKEUP;
+}
+#endif
+
 /*
  * The following function implements the controller interface for
  * the eventpoll file that enables the insertion/removal/change of
diff --git a/include/uapi/linux/eventpoll.h b/include/uapi/linux/eventpoll.h
index bc81fb2e1f0e..7850373079ee 100644
--- a/include/uapi/linux/eventpoll.h
+++ b/include/uapi/linux/eventpoll.h
@@ -61,16 +61,4 @@ struct epoll_event {
 	__u64 data;
 } EPOLL_PACKED;
 
-#ifdef CONFIG_PM_SLEEP
-static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
-{
-	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
-		epev->events &= ~EPOLLWAKEUP;
-}
-#else
-static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
-{
-	epev->events &= ~EPOLLWAKEUP;
-}
-#endif
 #endif /* _UAPI_LINUX_EVENTPOLL_H */
-- 
2.4.6

[PATCH 07/13] Make FB_BACKLIGHT_{LEVELS,MAX} always visible

[Palmer Dabbelt]

Nothing else in the kernel defines this, and this header is visible to
userspace.  Rather than hiding it in an #ifdef, I think it's sane to
just make this visible to userspace.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/fb.h | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/include/uapi/linux/fb.h b/include/uapi/linux/fb.h
index fb795c3b3c17..8926f13bc19f 100644
--- a/include/uapi/linux/fb.h
+++ b/include/uapi/linux/fb.h
@@ -392,11 +392,8 @@ struct fb_cursor {
 	struct fb_image	image;	/* Cursor image */
 };
 
-#ifdef CONFIG_FB_BACKLIGHT
 /* Settings for the generic backlight code */
 #define FB_BACKLIGHT_LEVELS	128
 #define FB_BACKLIGHT_MAX	0xFF
-#endif
-
 
 #endif /* _UAPI_LINUX_FB_H */
-- 
2.4.6

[PATCH 08/13] Move MAX_SHARED_LIBS to fs/binfmt_flat.c

[Palmer Dabbelt]

I'm not sure what this is, but it doesn't feel like something that
should be exposed to userspace here.  I'm assuming this file was
exposed for the structure in it, which doesn't depend on
MAX_SHARED_LIBS.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/binfmt_flat.c          | 6 ++++++
 include/uapi/linux/flat.h | 6 ------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index f723cd3a455c..e89fb43c2a10 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -72,6 +72,12 @@
 #define RELOC_FAILED 0xff00ff01		/* Relocation incorrect somewhere */
 #define UNLOADED_LIB 0x7ff000ff		/* Placeholder for unused library */
 
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+#define	MAX_SHARED_LIBS			(4)
+#else
+#define	MAX_SHARED_LIBS			(1)
+#endif
+
 struct lib_info {
 	struct {
 		unsigned long start_code;		/* Start of text segment */
diff --git a/include/uapi/linux/flat.h b/include/uapi/linux/flat.h
index 88cd6baba8f3..1b177c7637c4 100644
--- a/include/uapi/linux/flat.h
+++ b/include/uapi/linux/flat.h
@@ -13,12 +13,6 @@
 
 #define	FLAT_VERSION			0x00000004L
 
-#ifdef CONFIG_BINFMT_SHARED_FLAT
-#define	MAX_SHARED_LIBS			(4)
-#else
-#define	MAX_SHARED_LIBS			(1)
-#endif
-
 /*
  * To make everything easier to port and manage cross platform
  * development,  all fields are in network byte order.
-- 
2.4.6

[PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Palmer Dabbelt]

This has a "#ifdef CONFIG_*" that used to be exposed to userspace.

The names in here are so generic that I don't think it's a good idea
to expose them to userspace (or even the rest of the kernel).  Since
there's only one kernel user, it's been moved to that file.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/hw_breakpoint.h | 10 ----------
 kernel/events/hw_breakpoint.c      | 10 ++++++++++
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
index b04000a2296a..7a6a5a7f9511 100644
--- a/include/uapi/linux/hw_breakpoint.h
+++ b/include/uapi/linux/hw_breakpoint.h
@@ -17,14 +17,4 @@ enum {
 	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
 };
 
-enum bp_type_idx {
-	TYPE_INST 	= 0,
-#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
-	TYPE_DATA	= 0,
-#else
-	TYPE_DATA	= 1,
-#endif
-	TYPE_MAX
-};
-
 #endif /* _UAPI_LINUX_HW_BREAKPOINT_H */
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index 92ce5f4ccc26..5ad117e0f55b 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -58,6 +58,16 @@ struct bp_cpuinfo {
 	unsigned int	flexible; /* XXX: placeholder, see fetch_this_slot() */
 };
 
+enum bp_type_idx {
+	TYPE_INST	= 0,
+#if defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
+	TYPE_DATA	= 0,
+#else
+	TYPE_DATA	= 1,
+#endif
+	TYPE_MAX
+};
+
 static DEFINE_PER_CPU(struct bp_cpuinfo, bp_cpuinfo[TYPE_MAX]);
 static int nr_slots[TYPE_MAX];
 
-- 
2.4.6

[PATCH 10/13] Move USE_WCACHING to drivers/block/pktcdvd.c

[Palmer Dabbelt]

I don't think this was ever intended to be exposed to userspace, but
it did require an "#ifdef CONFIG_*".  Since the name is kind of
generic and was only used in one place, I've moved the definition to
the one user.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 drivers/block/pktcdvd.c      | 11 +++++++++++
 include/uapi/linux/pktcdvd.h | 11 -----------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 7be2375db7f2..18d2d05f5ac9 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -90,6 +90,17 @@ do {									\
 
 #define MAX_SPEED 0xffff
 
+/*
+ * use drive write caching -- we need deferred error handling to be
+ * able to successfully recover with this option (drive will return good
+ * status as soon as the cdb is validated).
+ */
+#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
+#define USE_WCACHING		1
+#else
+#define USE_WCACHING		0
+#endif
+
 static DEFINE_MUTEX(pktcdvd_mutex);
 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
 static struct proc_dir_entry *pkt_proc;
diff --git a/include/uapi/linux/pktcdvd.h b/include/uapi/linux/pktcdvd.h
index 2640b9d4e243..05c2bee70d6c 100644
--- a/include/uapi/linux/pktcdvd.h
+++ b/include/uapi/linux/pktcdvd.h
@@ -29,17 +29,6 @@
 #define PACKET_WAIT_TIME	(HZ * 5 / 1000)
 
 /*
- * use drive write caching -- we need deferred error handling to be
- * able to successfully recover with this option (drive will return good
- * status as soon as the cdb is validated).
- */
-#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
-#define USE_WCACHING		1
-#else
-#define USE_WCACHING		0
-#endif
-
-/*
  * No user-servicable parts beyond this point ->
  */
 
-- 
2.4.6

[PATCH 11/13] Always define MAX_RAW_MINORS as 65535 in userspace

[Palmer Dabbelt]

While I don't think this was ever meant to be exposed to userspace, if
anyone is using it then this will at least provide a correct (if
unlikely) definition.

MAX_RAW_MINORS used to be used in the kernel, where it's been replaced
with CONFIG_MAX_RAW_MINORS.

Note that there's a checkpatch.pl warning about a split config string
here, but I've left that alone.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 drivers/char/raw.c       | 7 ++++---
 include/uapi/linux/raw.h | 2 +-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index 60316fbaf295..362d7a6511b9 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -36,7 +36,7 @@ static struct raw_device_data *raw_devices;
 static DEFINE_MUTEX(raw_mutex);
 static const struct file_operations raw_ctl_fops; /* forward declaration */
 
-static int max_raw_minors = MAX_RAW_MINORS;
+static int max_raw_minors = CONFIG_MAX_RAW_MINORS;
 
 module_param(max_raw_minors, int, 0);
 MODULE_PARM_DESC(max_raw_minors, "Maximum number of raw devices (1-65536)");
@@ -317,8 +317,9 @@ static int __init raw_init(void)
 
 	if (max_raw_minors < 1 || max_raw_minors > 65536) {
 		printk(KERN_WARNING "raw: invalid max_raw_minors (must be"
-			" between 1 and 65536), using %d\n", MAX_RAW_MINORS);
-		max_raw_minors = MAX_RAW_MINORS;
+			" between 1 and 65536), using %d\n",
+		       CONFIG_MAX_RAW_MINORS);
+		max_raw_minors = CONFIG_MAX_RAW_MINORS;
 	}
 
 	raw_devices = vzalloc(sizeof(struct raw_device_data) * max_raw_minors);
diff --git a/include/uapi/linux/raw.h b/include/uapi/linux/raw.h
index 62d543e70603..f0390b3e8530 100644
--- a/include/uapi/linux/raw.h
+++ b/include/uapi/linux/raw.h
@@ -13,6 +13,6 @@ struct raw_config_request
 	__u64	block_minor;
 };
 
-#define MAX_RAW_MINORS CONFIG_MAX_RAW_DEVS
+#define MAX_RAW_MINORS 65535
 
 #endif /* __LINUX_RAW_H */
-- 
2.4.6

[PATCH 12/13] Remove AT_VECTOR_SIZE_ARCH on x86

[Palmer Dabbelt]

It looks like there aren't actually users of this macro anywhere:

 * The kernel doesn't use it on x86 because we don't suppor ELF FDPIC.

 * The only Google results point to LMKL patches, both the one that
   wrote this (from 2010) and my patch to hide it behind __KERNEL__.

 * I grep'd through all the source tarballs on my machine, and the
   only packages that matched were the kernel and crui (which copied a
   PPC kernel header).

Since I'm not sure how to actually provide the right answer (if I
understand correctly, CONFIG_IA32_EMULATION is not __i386__), the only
thing I can think of to do is to just remove the definition.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 arch/x86/include/uapi/asm/auxvec.h | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/x86/include/uapi/asm/auxvec.h b/arch/x86/include/uapi/asm/auxvec.h
index 77203ac352de..1316b4c35425 100644
--- a/arch/x86/include/uapi/asm/auxvec.h
+++ b/arch/x86/include/uapi/asm/auxvec.h
@@ -9,11 +9,4 @@
 #endif
 #define AT_SYSINFO_EHDR		33
 
-/* entries in ARCH_DLINFO: */
-#if defined(CONFIG_IA32_EMULATION) || !defined(CONFIG_X86_64)
-# define AT_VECTOR_SIZE_ARCH 2
-#else /* else it's non-compat x86-64 */
-# define AT_VECTOR_SIZE_ARCH 1
-#endif
-
 #endif /* _ASM_X86_AUXVEC_H */
-- 
2.4.6

[PATCH 13/13] Re-enable and clean up "check_config()" in headers_check.pl

[Palmer Dabbelt]

I recently got bit by a CONFIG_ in userspace bug.  This has apparently
happened before, but the check got disabled for triggering too much.
In order to reduce false positives, I added some hueristics to avoid
detecting comments.

Since these tests all pass, I've now re-enabled them.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 scripts/headers_check.pl | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/scripts/headers_check.pl b/scripts/headers_check.pl
index 62320f93e903..dd413ad9c850 100755
--- a/scripts/headers_check.pl
+++ b/scripts/headers_check.pl
@@ -40,7 +40,7 @@ foreach my $file (@files) {
 		&check_asm_types();
 		&check_sizetypes();
 		&check_declarations();
-		# Dropped for now. Too much noise &check_config();
+		&check_config();
 	}
 	close $fh;
 }
@@ -76,9 +76,24 @@ sub check_declarations
 	}
 }
 
+my $check_config_in_multiline_comment = 0;
 sub check_config
 {
-	if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
+	my $nocomments = $line;
+	$nocomments =~ s/\/\*.*\*\///; # Remove ANSI-style comments (/* to */)
+	$nocomments =~ s/\/\/.*//;     # Remove C99-style comments (// to EOL)
+
+	# Check to see if we're within a multiline comment, and if so
+	# just remove the whole line.  I tried matching on '^ * ', but
+	# there's one header that doesn't prepend multi-line comments
+	# with * so that won't work.
+	if ($nocomments =~ m/\/\*/) { $check_config_in_multiline_comment = 1; }
+	if ($nocomments =~ m/\*\//) { $check_config_in_multiline_comment = 0; }
+	if ($check_config_in_multiline_comment == 1) { $nocomments = "" }
+
+	# Check to see if there is something that looks like CONFIG_
+	# inside a userspace-accessible header file and if so, print that out.
+	if ($nocomments =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
 		printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n";
 	}
 }
-- 
2.4.6

Re: [PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Kirill A. Shutemov]

On Mon, Sep 14, 2015 at 03:50:38PM -0700, Palmer Dabbelt wrote:
> This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
> userspace wouldn't actually ever see it be non-zero.  While I could
> have kept hiding it, the man pages seem to indicate that
> MAP_UNINITIALIZED should be visible:
> 
>   mmap(2)
>   MAP_UNINITIALIZED (since Linux 2.6.33)
>     Don't clear anonymous pages.  This flag is intended to improve
>     performance on embedded devices.  This flag is honored only if the
>     kernel was configured with the CONFIG_MMAP_ALLOW_UNINITIALIZED
>     option.  Because of the security implications, that option is
>     normally enabled only on embedded devices (i.e., devices where one
>     has complete control of the contents of user memory).
> 
> and since the only time it shows up in my /usr/include is in this
> header I believe this should have been visible to userspace (as
> non-zero, which wouldn't do anything when or'd into the flags) all
> along.

Are you sure about "wouldn't do anything"?
Suspiciously, 0x4000000 is also (1 << MAP_HUGE_SHIFT). I'm not sure if any
architecture has order-1 huge pages, but still looks like we have conflict
here.

I think it's harmful to expose non-zero MAP_UNINITIALIZED to system which
potentially can handle multiple users. Or non-trivial user space in
general.

Should we leave it at least under '#ifndef CONFIG_MMU'? I don't think it's
possible to have single ABI for MMU and MMU-less systems anyway. And we
can avoid conflict with MAP_HUGE_SHIFT this way.

P.S. MAP_UNINITIALIZED itself looks very broken to me. I probably need dig
mailing list on why it was allowed. 
But that's other topic.

-- 
 Kirill A. Shutemov

Re: [PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Palmer Dabbelt]

On Mon, 14 Sep 2015 17:23:58 PDT (-0700), kirill@shutemov.name wrote:
> On Mon, Sep 14, 2015 at 03:50:38PM -0700, Palmer Dabbelt wrote:
>> This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
>> userspace wouldn't actually ever see it be non-zero.  While I could
>> have kept hiding it, the man pages seem to indicate that
>> MAP_UNINITIALIZED should be visible:
>>
>>   mmap(2)
>>   MAP_UNINITIALIZED (since Linux 2.6.33)
>>     Don't clear anonymous pages.  This flag is intended to improve
>>     performance on embedded devices.  This flag is honored only if the
>>     kernel was configured with the CONFIG_MMAP_ALLOW_UNINITIALIZED
>>     option.  Because of the security implications, that option is
>>     normally enabled only on embedded devices (i.e., devices where one
>>     has complete control of the contents of user memory).
>>
>> and since the only time it shows up in my /usr/include is in this
>> header I believe this should have been visible to userspace (as
>> non-zero, which wouldn't do anything when or'd into the flags) all
>> along.
>
> Are you sure about "wouldn't do anything"?

That was bad writing for me.  I'd originally written something like "I
believe this should have been visible to userspace all along", but
then added the ()'s.  I meant to say:

 * I think MAP_UNINITIALIZED should have been non-zero in userspace.
 * MAP_UNINITAILIZED was zero in userspace.
 * A zero MAP_UNINITIALIZED does nothing when OR'd in.

> Suspiciously, 0x4000000 is also (1 << MAP_HUGE_SHIFT). I'm not sure if any
> architecture has order-1 huge pages, but still looks like we have conflict
> here.
>
> I think it's harmful to expose non-zero MAP_UNINITIALIZED to system which
> potentially can handle multiple users. Or non-trivial user space in
> general.

This doesn't have MAP_UNINITIALIZED do anything by default, it just
defines the flag the same way on all systems.  I was under the
impression that this just happened if I set MAP_UNINITIALIZED.
Looking at MAP_HUGE_SHIFT it mmap.c, that's definitely why my mmap()
test case ignored the set MAP_UNINITIALIZED on my PC.

I'm going to make this

 #ifndef MAP_UNINITAILIZED
 #define MAP_UNINITAILIZED 0
 #endif

and then leave Xtensa's port alone.  This is what Arnd suggested
originally, sorry for the extra work!

> Should we leave it at least under '#ifndef CONFIG_MMU'? I don't think it's
> possible to have single ABI for MMU and MMU-less systems anyway. And we
> can avoid conflict with MAP_HUGE_SHIFT this way.

The whole goal here was to eliminate "#ifndef CONFIG_*" from the
user-visible headers.  This all started because I got bit by a very
similar-looking bug (see patch #1), so I'd prefer not to go down that
route.

> P.S. MAP_UNINITIALIZED itself looks very broken to me. I probably need dig
> mailing list on why it was allowed.
> But that's other topic.

Re: [PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Josh Triplett]

On Tue, Sep 15, 2015 at 03:23:58AM +0300, Kirill A. Shutemov wrote:
> On Mon, Sep 14, 2015 at 03:50:38PM -0700, Palmer Dabbelt wrote:
> > This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
> > userspace wouldn't actually ever see it be non-zero.  While I could
> > have kept hiding it, the man pages seem to indicate that
> > MAP_UNINITIALIZED should be visible:
> > 
> >   mmap(2)
> >   MAP_UNINITIALIZED (since Linux 2.6.33)
> >     Don't clear anonymous pages.  This flag is intended to improve
> >     performance on embedded devices.  This flag is honored only if the
> >     kernel was configured with the CONFIG_MMAP_ALLOW_UNINITIALIZED
> >     option.  Because of the security implications, that option is
> >     normally enabled only on embedded devices (i.e., devices where one
> >     has complete control of the contents of user memory).
> > 
> > and since the only time it shows up in my /usr/include is in this
> > header I believe this should have been visible to userspace (as
> > non-zero, which wouldn't do anything when or'd into the flags) all
> > along.
> 
> Are you sure about "wouldn't do anything"?
> Suspiciously, 0x4000000 is also (1 << MAP_HUGE_SHIFT). I'm not sure if any
> architecture has order-1 huge pages, but still looks like we have conflict
> here.
> 
> I think it's harmful to expose non-zero MAP_UNINITIALIZED to system which
> potentially can handle multiple users. Or non-trivial user space in
> general.

The flag should always exist.  If it was defined to conflict with
something else, that's a serious ABI problem.  But the flag
should always exist, even if the kernel ends up ignoring it.

> Should we leave it at least under '#ifndef CONFIG_MMU'? I don't think it's
> possible to have single ABI for MMU and MMU-less systems anyway. And we
> can avoid conflict with MAP_HUGE_SHIFT this way.

No; even if you have an MMU (which is useful for things like fork()), a
system without user separation (for instance, without CONFIG_MULTIUSER)
can reasonably use MAP_UNINITIALIZED.

> P.S. MAP_UNINITIALIZED itself looks very broken to me. I probably need dig
> mailing list on why it was allowed.

That's what the config option *and* explicit flag are for; there are
more than enough warnings about the implications.

- Josh Triplett

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Peter Zijlstra]

On Mon, Sep 14, 2015 at 03:50:43PM -0700, Palmer Dabbelt wrote:
> This has a "#ifdef CONFIG_*" that used to be exposed to userspace.
> 
> The names in here are so generic that I don't think it's a good idea
> to expose them to userspace (or even the rest of the kernel).  Since
> there's only one kernel user, it's been moved to that file.
> 
> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
> ---
>  include/uapi/linux/hw_breakpoint.h | 10 ----------
>  kernel/events/hw_breakpoint.c      | 10 ++++++++++
>  2 files changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
> index b04000a2296a..7a6a5a7f9511 100644
> --- a/include/uapi/linux/hw_breakpoint.h
> +++ b/include/uapi/linux/hw_breakpoint.h
> @@ -17,14 +17,4 @@ enum {
>  	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
>  };
>  
> -enum bp_type_idx {
> -	TYPE_INST 	= 0,
> -#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
> -	TYPE_DATA	= 0,
> -#else
> -	TYPE_DATA	= 1,
> -#endif
> -	TYPE_MAX
> -};

This is rather unfortunate; you are correct that the naming is too
generic (and I tend to agree), but I think these values are required by
userspace to fill out:

  perf_event_attr::bp_type

So removing them will break things.

Frederic?

Re: [PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Kirill A. Shutemov]

On Mon, Sep 14, 2015 at 10:19:19PM -0700, Josh Triplett wrote:
> On Tue, Sep 15, 2015 at 03:23:58AM +0300, Kirill A. Shutemov wrote:
> > On Mon, Sep 14, 2015 at 03:50:38PM -0700, Palmer Dabbelt wrote:
> > > This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
> > > userspace wouldn't actually ever see it be non-zero.  While I could
> > > have kept hiding it, the man pages seem to indicate that
> > > MAP_UNINITIALIZED should be visible:
> > > 
> > >   mmap(2)
> > >   MAP_UNINITIALIZED (since Linux 2.6.33)
> > >     Don't clear anonymous pages.  This flag is intended to improve
> > >     performance on embedded devices.  This flag is honored only if the
> > >     kernel was configured with the CONFIG_MMAP_ALLOW_UNINITIALIZED
> > >     option.  Because of the security implications, that option is
> > >     normally enabled only on embedded devices (i.e., devices where one
> > >     has complete control of the contents of user memory).
> > > 
> > > and since the only time it shows up in my /usr/include is in this
> > > header I believe this should have been visible to userspace (as
> > > non-zero, which wouldn't do anything when or'd into the flags) all
> > > along.
> > 
> > Are you sure about "wouldn't do anything"?
> > Suspiciously, 0x4000000 is also (1 << MAP_HUGE_SHIFT). I'm not sure if any
> > architecture has order-1 huge pages, but still looks like we have conflict
> > here.
> > 
> > I think it's harmful to expose non-zero MAP_UNINITIALIZED to system which
> > potentially can handle multiple users. Or non-trivial user space in
> > general.
> 
> The flag should always exist.

Sure. And 0 is perfectly fine value for the flag. Like with MAP_FILE.

> If it was defined to conflict with
> something else, that's a serious ABI problem.  But the flag
> should always exist, even if the kernel ends up ignoring it.
> 
> > Should we leave it at least under '#ifndef CONFIG_MMU'? I don't think it's
> > possible to have single ABI for MMU and MMU-less systems anyway. And we
> > can avoid conflict with MAP_HUGE_SHIFT this way.
> 
> No; even if you have an MMU (which is useful for things like fork()), a
> system without user separation (for instance, without CONFIG_MULTIUSER)
> can reasonably use MAP_UNINITIALIZED.

Can? Yes. Reasonably? I don't think so.

> > P.S. MAP_UNINITIALIZED itself looks very broken to me. I probably need dig
> > mailing list on why it was allowed.
> 
> That's what the config option *and* explicit flag are for; there are
> more than enough warnings about the implications.

I think it's misdesigned. It doesn't require explicid opt-in from a
process who owned the page allocated in MAP_UNINITIALIZED mapping before.

#define MAP_LEAK_ME_SOME_DATA MAP_UNINITIALIZED

-- 
 Kirill A. Shutemov

Re: [PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Josh Triplett]

On Tue, Sep 15, 2015 at 12:42:00PM +0300, Kirill A. Shutemov wrote:
> On Mon, Sep 14, 2015 at 10:19:19PM -0700, Josh Triplett wrote:
> > On Tue, Sep 15, 2015 at 03:23:58AM +0300, Kirill A. Shutemov wrote:
> > > On Mon, Sep 14, 2015 at 03:50:38PM -0700, Palmer Dabbelt wrote:
> > > > This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
> > > > userspace wouldn't actually ever see it be non-zero.  While I could
> > > > have kept hiding it, the man pages seem to indicate that
> > > > MAP_UNINITIALIZED should be visible:
> > > > 
> > > >   mmap(2)
> > > >   MAP_UNINITIALIZED (since Linux 2.6.33)
> > > >     Don't clear anonymous pages.  This flag is intended to improve
> > > >     performance on embedded devices.  This flag is honored only if the
> > > >     kernel was configured with the CONFIG_MMAP_ALLOW_UNINITIALIZED
> > > >     option.  Because of the security implications, that option is
> > > >     normally enabled only on embedded devices (i.e., devices where one
> > > >     has complete control of the contents of user memory).
> > > > 
> > > > and since the only time it shows up in my /usr/include is in this
> > > > header I believe this should have been visible to userspace (as
> > > > non-zero, which wouldn't do anything when or'd into the flags) all
> > > > along.
> > > 
> > > Are you sure about "wouldn't do anything"?
> > > Suspiciously, 0x4000000 is also (1 << MAP_HUGE_SHIFT). I'm not sure if any
> > > architecture has order-1 huge pages, but still looks like we have conflict
> > > here.
> > > 
> > > I think it's harmful to expose non-zero MAP_UNINITIALIZED to system which
> > > potentially can handle multiple users. Or non-trivial user space in
> > > general.
> > 
> > The flag should always exist.
> 
> Sure. And 0 is perfectly fine value for the flag. Like with MAP_FILE.

Rephrasing: the flag should always exist with the correct value.
Whether the kernel handles it or not, the kernel *headers* shouldn't
change to match the kernel, not least of which because they don't
necessarily match the running kernel.  Just like we define the
prototypes for syscalls that the running kernel may return ENOSYS for.

> > If it was defined to conflict with
> > something else, that's a serious ABI problem.  But the flag
> > should always exist, even if the kernel ends up ignoring it.
> > 
> > > Should we leave it at least under '#ifndef CONFIG_MMU'? I don't think it's
> > > possible to have single ABI for MMU and MMU-less systems anyway. And we
> > > can avoid conflict with MAP_HUGE_SHIFT this way.
> > 
> > No; even if you have an MMU (which is useful for things like fork()), a
> > system without user separation (for instance, without CONFIG_MULTIUSER)
> > can reasonably use MAP_UNINITIALIZED.
> 
> Can? Yes. Reasonably? I don't think so.

Not all systems care.  Otherwise you should be complaining more bitterly
about options like CONFIG_MMU=n, which (*gasp*) allow access to *arbitrary
memory*.

> > > P.S. MAP_UNINITIALIZED itself looks very broken to me. I probably need dig
> > > mailing list on why it was allowed.
> > 
> > That's what the config option *and* explicit flag are for; there are
> > more than enough warnings about the implications.
> 
> I think it's misdesigned. It doesn't require explicid opt-in from a
> process who owned the page allocated in MAP_UNINITIALIZED mapping before.
> 
> #define MAP_LEAK_ME_SOME_DATA MAP_UNINITIALIZED

Hence why it has a config option.

The userspace option exists primarily because otherwise userspace might
get surprised by receiving a non-zeroed page.  On a system with the
config option turned on, processes have access to arbitrary freed
memory, as long as they say they can handle not having their memory
pre-zeroed.

- Josh Triplett

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Palmer Dabbelt]

On Tue, 15 Sep 2015 01:06:07 PDT (-0700), peterz@infradead.org wrote:
> On Mon, Sep 14, 2015 at 03:50:43PM -0700, Palmer Dabbelt wrote:
>> This has a "#ifdef CONFIG_*" that used to be exposed to userspace.
>>
>> The names in here are so generic that I don't think it's a good idea
>> to expose them to userspace (or even the rest of the kernel).  Since
>> there's only one kernel user, it's been moved to that file.
>>
>> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
>> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
>> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
>> ---
>>  include/uapi/linux/hw_breakpoint.h | 10 ----------
>>  kernel/events/hw_breakpoint.c      | 10 ++++++++++
>>  2 files changed, 10 insertions(+), 10 deletions(-)
>>
>> diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
>> index b04000a2296a..7a6a5a7f9511 100644
>> --- a/include/uapi/linux/hw_breakpoint.h
>> +++ b/include/uapi/linux/hw_breakpoint.h
>> @@ -17,14 +17,4 @@ enum {
>>  	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
>>  };
>>
>> -enum bp_type_idx {
>> -	TYPE_INST 	= 0,
>> -#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
>> -	TYPE_DATA	= 0,
>> -#else
>> -	TYPE_DATA	= 1,
>> -#endif
>> -	TYPE_MAX
>> -};
>
> This is rather unfortunate; you are correct that the naming is too
> generic (and I tend to agree), but I think these values are required by
> userspace to fill out:
>
>   perf_event_attr::bp_type
>
> So removing them will break things.
>
> Frederic?

perf_event_open(2) says

       bp_type (since Linux 2.6.33)
              This chooses the breakpoint type.  It is one of:

              HW_BREAKPOINT_EMPTY
                     No breakpoint.

              HW_BREAKPOINT_R
                     Count when we read the memory location.

              HW_BREAKPOINT_W
                     Count when we write the memory location.

              HW_BREAKPOINT_RW
                     Count when we read or write the memory location.

              HW_BREAKPOINT_X
                     Count when we execute code at the memory location.

              The values can be combined via a bitwise or, but the combination
              of HW_BREAKPOINT_R or HW_BREAKPOINT_W  with  HW_BREAKPOINT_X  is
              not allowed.

so I think removing this enum from userspace is OK.  Did I miss
something?

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Peter Zijlstra]

On Tue, Sep 15, 2015 at 11:40:11AM -0700, Palmer Dabbelt wrote:
> On Tue, 15 Sep 2015 01:06:07 PDT (-0700), peterz@infradead.org wrote:
> > On Mon, Sep 14, 2015 at 03:50:43PM -0700, Palmer Dabbelt wrote:
> >> This has a "#ifdef CONFIG_*" that used to be exposed to userspace.
> >>
> >> The names in here are so generic that I don't think it's a good idea
> >> to expose them to userspace (or even the rest of the kernel).  Since
> >> there's only one kernel user, it's been moved to that file.
> >>
> >> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
> >> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
> >> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
> >> ---
> >>  include/uapi/linux/hw_breakpoint.h | 10 ----------
> >>  kernel/events/hw_breakpoint.c      | 10 ++++++++++
> >>  2 files changed, 10 insertions(+), 10 deletions(-)
> >>
> >> diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
> >> index b04000a2296a..7a6a5a7f9511 100644
> >> --- a/include/uapi/linux/hw_breakpoint.h
> >> +++ b/include/uapi/linux/hw_breakpoint.h
> >> @@ -17,14 +17,4 @@ enum {
> >>  	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
> >>  };
> >>
> >> -enum bp_type_idx {
> >> -	TYPE_INST 	= 0,
> >> -#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
> >> -	TYPE_DATA	= 0,
> >> -#else
> >> -	TYPE_DATA	= 1,
> >> -#endif
> >> -	TYPE_MAX
> >> -};
> >
> > This is rather unfortunate; you are correct that the naming is too
> > generic (and I tend to agree), but I think these values are required by
> > userspace to fill out:
> >
> >   perf_event_attr::bp_type
> >
> > So removing them will break things.
> >
> > Frederic?
> 
> perf_event_open(2) says
> 
>        bp_type (since Linux 2.6.33)
>               This chooses the breakpoint type.  It is one of:
> 
>               HW_BREAKPOINT_EMPTY
>                      No breakpoint.
> 
>               HW_BREAKPOINT_R
>                      Count when we read the memory location.
> 
>               HW_BREAKPOINT_W
>                      Count when we write the memory location.
> 
>               HW_BREAKPOINT_RW
>                      Count when we read or write the memory location.
> 
>               HW_BREAKPOINT_X
>                      Count when we execute code at the memory location.
> 
>               The values can be combined via a bitwise or, but the combination
>               of HW_BREAKPOINT_R or HW_BREAKPOINT_W  with  HW_BREAKPOINT_X  is
>               not allowed.
> 
> so I think removing this enum from userspace is OK.  Did I miss
> something?

Nah, could've just been me not being awake. Unless Frederic says
otherwise I'll chalk it up to not having drank enough morning juice.

Re: [PATCH 11/13] Always define MAX_RAW_MINORS as 65535 in userspace

[H. Peter Anvin]

On 09/14/2015 03:50 PM, Palmer Dabbelt wrote:
> While I don't think this was ever meant to be exposed to userspace, if
> anyone is using it then this will at least provide a correct (if
> unlikely) definition.
> 
> MAX_RAW_MINORS used to be used in the kernel, where it's been replaced
> with CONFIG_MAX_RAW_MINORS.
> 
> Note that there's a checkpatch.pl warning about a split config string
> here, but I've left that alone.

>From a UAPI perspective I would think the right value would be 2^20.

	-hpa

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Arnd Bergmann]

On Tuesday 15 September 2015 10:06:07 Peter Zijlstra wrote:
> > diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
> > index b04000a2296a..7a6a5a7f9511 100644
> > --- a/include/uapi/linux/hw_breakpoint.h
> > +++ b/include/uapi/linux/hw_breakpoint.h
> > @@ -17,14 +17,4 @@ enum {
> >       HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
> >  };
> >  
> > -enum bp_type_idx {
> > -     TYPE_INST       = 0,
> > -#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
> > -     TYPE_DATA       = 0,
> > -#else
> > -     TYPE_DATA       = 1,
> > -#endif
> > -     TYPE_MAX
> > -};
> 
> This is rather unfortunate; you are correct that the naming is too
> generic (and I tend to agree), but I think these values are required by
> userspace to fill out:
> 
>   perf_event_attr::bp_type
> 
> So removing them will break things.
> 
> Frederic?

If user space actually relies on the definition from this header file,
then it will use the wrong one on x86 and get 'TYPE_DATA = 1', while the
kernel uses 'TYPE_DATA = 0'.

That seems unlikely to work, so I suspect it gets a different definition.
If it uses this definition and it does work, we can probably use

#if defined(__KERNEL__) && defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)

but that requires a comment explaining exactly why that works.

	Arnd

Re: [PATCH 11/13] Always define MAX_RAW_MINORS as 65535 in userspace

[Palmer Dabbelt]

On Tue, 15 Sep 2015 13:42:47 PDT (-0700), hpa@zytor.com wrote:
> On 09/14/2015 03:50 PM, Palmer Dabbelt wrote:
>> While I don't think this was ever meant to be exposed to userspace, if
>> anyone is using it then this will at least provide a correct (if
>> unlikely) definition.
>>
>> MAX_RAW_MINORS used to be used in the kernel, where it's been replaced
>> with CONFIG_MAX_RAW_MINORS.
>>
>> Note that there's a checkpatch.pl warning about a split config string
>> here, but I've left that alone.
>
> From a UAPI perspective I would think the right value would be 2^20.

Wow, I'm super surprised.  For some reason I thought major/minor
numbers were 16 bits, but according to glibc I just have no idea what
I'm doing :).

Thanks for catching this!

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Palmer Dabbelt]

On Tue, 15 Sep 2015 12:39:10 PDT (-0700), peterz@infradead.org wrote:
> On Tue, Sep 15, 2015 at 11:40:11AM -0700, Palmer Dabbelt wrote:
>> On Tue, 15 Sep 2015 01:06:07 PDT (-0700), peterz@infradead.org wrote:
>> > On Mon, Sep 14, 2015 at 03:50:43PM -0700, Palmer Dabbelt wrote:
>> >> This has a "#ifdef CONFIG_*" that used to be exposed to userspace.
>> >>
>> >> The names in here are so generic that I don't think it's a good idea
>> >> to expose them to userspace (or even the rest of the kernel).  Since
>> >> there's only one kernel user, it's been moved to that file.
>> >>
>> >> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
>> >> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
>> >> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
>> >> ---
>> >>  include/uapi/linux/hw_breakpoint.h | 10 ----------
>> >>  kernel/events/hw_breakpoint.c      | 10 ++++++++++
>> >>  2 files changed, 10 insertions(+), 10 deletions(-)
>> >>
>> >> diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
>> >> index b04000a2296a..7a6a5a7f9511 100644
>> >> --- a/include/uapi/linux/hw_breakpoint.h
>> >> +++ b/include/uapi/linux/hw_breakpoint.h
>> >> @@ -17,14 +17,4 @@ enum {
>> >>  	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
>> >>  };
>> >>
>> >> -enum bp_type_idx {
>> >> -	TYPE_INST 	= 0,
>> >> -#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
>> >> -	TYPE_DATA	= 0,
>> >> -#else
>> >> -	TYPE_DATA	= 1,
>> >> -#endif
>> >> -	TYPE_MAX
>> >> -};
>> >
>> > This is rather unfortunate; you are correct that the naming is too
>> > generic (and I tend to agree), but I think these values are required by
>> > userspace to fill out:
>> >
>> >   perf_event_attr::bp_type
>> >
>> > So removing them will break things.
>> >
>> > Frederic?
>>
>> perf_event_open(2) says
>>
>>        bp_type (since Linux 2.6.33)
>>               This chooses the breakpoint type.  It is one of:
>>
>>               HW_BREAKPOINT_EMPTY
>>                      No breakpoint.
>>
>>               HW_BREAKPOINT_R
>>                      Count when we read the memory location.
>>
>>               HW_BREAKPOINT_W
>>                      Count when we write the memory location.
>>
>>               HW_BREAKPOINT_RW
>>                      Count when we read or write the memory location.
>>
>>               HW_BREAKPOINT_X
>>                      Count when we execute code at the memory location.
>>
>>               The values can be combined via a bitwise or, but the combination
>>               of HW_BREAKPOINT_R or HW_BREAKPOINT_W  with  HW_BREAKPOINT_X  is
>>               not allowed.
>>
>> so I think removing this enum from userspace is OK.  Did I miss
>> something?
>
> Nah, could've just been me not being awake. Unless Frederic says
> otherwise I'll chalk it up to not having drank enough morning juice.

Well, I'm going to leave this alone, then -- as Arnd pointed out in a
later email that got mis-threaded, this would be super tricky to fix
if userspace actually relied on it (which is why I was scared I was
wrong).

v4 (which is hopefully the final version of the patch set) will leave
this as it is.

Re: [PATCH 03/13] Move COMPAT_ATM_ADDPARTY to net/atm/svc.c

[David Howells]

Palmer Dabbelt <palmer@dabbelt.com> wrote:

> +#ifdef CONFIG_COMPAT
> +/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
> +#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4, struct compat_atm_iobuf)
> +#endif

I wonder if it would hurt to ditch the conditionals entirely.  It only eats
cpp namespace, not C namespace so it won't affect the output if it is not used
because the code that uses it is compiled out.

David

Re: [PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[David Howells]

Josh Triplett <josh@joshtriplett.org> wrote:

> > Sure. And 0 is perfectly fine value for the flag. Like with MAP_FILE.
> 
> Rephrasing: the flag should always exist with the correct value.
> Whether the kernel handles it or not, the kernel *headers* shouldn't
> change to match the kernel, not least of which because they don't
> necessarily match the running kernel.  Just like we define the
> prototypes for syscalls that the running kernel may return ENOSYS for.

Josh is correct.

CONFIG_xxx *should* *not* be seen in UAPI headers, except inside #ifdef
__KERNEL__ guards under special circumstances - and #ifdef __KERNEL__ guards
*should* *not* be seen in UAPI headers except under special circumstances.

In terms of such special circumstances, take a peek in
include/uapi/linux/acct.h at struct acct with this:

	/* m68k had no padding here. */
	#if !defined(CONFIG_M68K) || !defined(__KERNEL__)
		__u16		ac_ahz;			/* AHZ */
	#endif

in the middle of it...

Or include/{,uapi/}linux/agpgart.h where it defines two different but
same-named variants of several structs.

Now, some of these - particularly things like the latter - can be fixed by
someone who has the time.

David

Re: [PATCH 05/13] Split FDPIC "struct elf_prstatus" to "struct elf_fdpic_prstatus"

[David Howells]

Palmer Dabbelt <palmer@dabbelt.com> wrote:

> I tried to fix all the users of "struct elf_prstatus" that should now
> be using "struct elf_fdpic_prstatus".  The only testing I did here was
> to build a Blackfin defconfig with "struct elf_prstatus" not defined,
> and to build an x86 defconfig with "struct elf_fdpic_prstatus" not
> defined.

You probably also need to try loading a core into a debugger.

David

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[David Howells]

Arnd Bergmann <arnd@arndb.de> wrote:

> That seems unlikely to work, so I suspect it gets a different definition.
> If it uses this definition and it does work, we can probably use
> 
> #if defined(__KERNEL__) && defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
> 
> but that requires a comment explaining exactly why that works.

Are you suggesting wrapping the entire construct in this within the UAPI
header?

David

Re: [PATCH 03/13] Move COMPAT_ATM_ADDPARTY to net/atm/svc.c

[Palmer Dabbelt]

On Thu, 17 Sep 2015 02:57:12 PDT (-0700), dhowells@redhat.com wrote:
> Palmer Dabbelt <palmer@dabbelt.com> wrote:
>
>> +#ifdef CONFIG_COMPAT
>> +/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
>> +#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4, struct compat_atm_iobuf)
>> +#endif
>
> I wonder if it would hurt to ditch the conditionals entirely.  It only eats
> cpp namespace, not C namespace so it won't affect the output if it is not used
> because the code that uses it is compiled out.

Makes sense to me.

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Frederic Weisbecker]

On Tue, Sep 15, 2015 at 11:15:29PM +0200, Arnd Bergmann wrote:
> On Tuesday 15 September 2015 10:06:07 Peter Zijlstra wrote:
> > > diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
> > > index b04000a2296a..7a6a5a7f9511 100644
> > > --- a/include/uapi/linux/hw_breakpoint.h
> > > +++ b/include/uapi/linux/hw_breakpoint.h
> > > @@ -17,14 +17,4 @@ enum {
> > >       HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
> > >  };
> > >  
> > > -enum bp_type_idx {
> > > -     TYPE_INST       = 0,
> > > -#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
> > > -     TYPE_DATA       = 0,
> > > -#else
> > > -     TYPE_DATA       = 1,
> > > -#endif
> > > -     TYPE_MAX
> > > -};
> > 
> > This is rather unfortunate; you are correct that the naming is too
> > generic (and I tend to agree), but I think these values are required by
> > userspace to fill out:
> > 
> >   perf_event_attr::bp_type
> > 
> > So removing them will break things.
> > 
> > Frederic?
> 
> If user space actually relies on the definition from this header file,
> then it will use the wrong one on x86 and get 'TYPE_DATA = 1', while the
> kernel uses 'TYPE_DATA = 0'.
> 
> That seems unlikely to work, so I suspect it gets a different definition.
> If it uses this definition and it does work, we can probably use
> 
> #if defined(__KERNEL__) && defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
> 
> but that requires a comment explaining exactly why that works.

I think this TYPE_DATA/TYPE_INST can be safely removed from uapi. This is only
about internal kernel code. Userspace only relies on HW_BREAKPOINT_[R/W/X]
to tell about the nature of the breakpoint.

If userspace ever relies on it, which I have no idea why, it even needs to define
CONFIG_HAVE_MIXED_BREAKPOINTS_REGS. No really there shouldn't be any user of that outside
the kernel.

Thanks.

> 
> 	Arnd

[PATCH v4] Remove #ifdef CONFIG_* from all userspace headers

[Palmer Dabbelt]

I think this is good to go.  There are two acks, but I wasn't sure if I was
supposed to collect them in the patches or not.  Arnd Bergman acked #1 and #7.

Changes since v3 (<1442271047-4908-1-git-send-email-palmer@dabbelt.com>)

 * #4 is very different: rather than defining a canonical value for
   MAP_UNINITIALIZED, it just punts on the problem and lets arch maintainers
   deal with it.  There's still an #ifndef MAP_UNINITIALIZED in there, but that
   shouldn't get triggered by anything because the arch headers should set it
   to whatever they actually want.

 * #11 defines MAX_RAW_MINORS to 2^20 instead of 2^16.

 * #13 moves the variable around a bit so it gets initialized.  I forgot I was
   in perl and not C :).

Changes since v2 (<1441832902-28993-1-git-send-email-palmer@dabbelt.com>)

 * Patch set renamed.

 * #2 is rewritten to use sys_ni.c instead of an #ifdef

 * #3, #6, #8, #9, #10, and #11 no longer use "#ifdef __KERNEL__" but
   have instead moved the offending lines to the correct, kernel-only
   files.

 * #4 has been rewritten to always define MAP_UNINITIALIZED to
   non-zero, rather than defining it to zero when in userspace.

 * #5 got a whole lot longer -- rather than just always hiding these
   fields from userspace, there is now a second "struct
   elf_fdpic_prstatus" structure.  This should allow userspace to
   parse core dumps correctly.

 * Rebased onto 9c488de24f7264f08d341024bffdd637b4d04c96.

Changes since v1 (<1441152610-22566-1-git-send-email-palmer@dabbelt.com>)

 * All patches but #1 were added.

[PATCH 01/13] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[Palmer Dabbelt]

When working on the RISC-V port I noticed that F_SETLK64 was being
defined on our 64-bit platform, despite our port being so new that
we've only ever had the 64-bit file ops.  Since there's not compat
layer for these, this causes fcntl to bail out.

It turns out that one of the ways in with F_SETLK64 was being defined
(there's some more in glibc, but that's a whole different story... :))
is the result of CONFIG_64BIT showing up in this user-visible header.
<asm-generic/bitsperlong.h> confirms this isn't sane, so I replaced it
with a __BITS_PER_LONG check.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/fcntl.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
index e063eff..14a5c82 100644
--- a/include/uapi/asm-generic/fcntl.h
+++ b/include/uapi/asm-generic/fcntl.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_GENERIC_FCNTL_H
 #define _ASM_GENERIC_FCNTL_H
 
+#include <asm/bitsperlong.h>
 #include <linux/types.h>
 
 /*
@@ -115,7 +116,7 @@
 #define F_GETSIG	11	/* for sockets. */
 #endif
 
-#ifndef CONFIG_64BIT
+#if (__BITS_PER_LONG == 32)
 #ifndef F_GETLK64
 #define F_GETLK64	12	/*  using 'struct flock64' */
 #define F_SETLK64	13
-- 
2.4.10

[PATCH 02/13] Use sys_ni.c instead of #ifdef to disable fork on CONFIG_NOMMU

[Palmer Dabbelt]

I think this change actually doesn't do anything: __NR_fork was still
being defined either way, and on my machine fork() in <unistd.h> comes
from libc.

This just moves to the standard mechanism for defining syscalls that
aren't implemented instead, which has the side-effect of no longer
having an #ifdef CONFIG_* in a user-visible header.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/unistd.h | 4 ----
 kernel/sys_ni.c                   | 1 +
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index ee12400..ffd2957 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -869,11 +869,7 @@ __SYSCALL(__NR_uselib, sys_uselib)
 __SYSCALL(__NR__sysctl, sys_sysctl)
 
 #define __NR_fork 1079
-#ifdef CONFIG_MMU
 __SYSCALL(__NR_fork, sys_fork)
-#else
-__SYSCALL(__NR_fork, sys_ni_syscall)
-#endif /* CONFIG_MMU */
 
 #undef __NR_syscalls
 #define __NR_syscalls (__NR_fork+1)
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index a02decf..c830f7f 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -174,6 +174,7 @@ cond_syscall(sys_setfsuid);
 cond_syscall(sys_setfsgid);
 cond_syscall(sys_capget);
 cond_syscall(sys_capset);
+cond_syscall(sys_fork);
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read);
-- 
2.4.10

[PATCH 03/13] Move COMPAT_ATM_ADDPARTY to net/atm/svc.c

[Palmer Dabbelt]

This used to be behind an #ifdef COMPAT_COMPAT, so most of userspace
wouldn't have seen the definition before.  Unfortunately this header
file became visible to userspace, so the definition has instead been
moved to net/atm/svc.c (the only user).

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/atmdev.h | 4 ----
 net/atm/svc.c               | 5 +++++
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/atmdev.h b/include/uapi/linux/atmdev.h
index 93e0ec0..3dcec70 100644
--- a/include/uapi/linux/atmdev.h
+++ b/include/uapi/linux/atmdev.h
@@ -100,10 +100,6 @@ struct atm_dev_stats {
 					/* use backend to make new if */
 #define ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct atm_iobuf)
  					/* add party to p2mp call */
-#ifdef CONFIG_COMPAT
-/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
-#define COMPAT_ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct compat_atm_iobuf)
-#endif
 #define ATM_DROPPARTY 	_IOW('a', ATMIOC_SPECIAL+5,int)
 					/* drop party from p2mp call */
 
diff --git a/net/atm/svc.c b/net/atm/svc.c
index 3fa0a9e..9e2e6ef 100644
--- a/net/atm/svc.c
+++ b/net/atm/svc.c
@@ -27,6 +27,11 @@
 #include "signaling.h"
 #include "addr.h"
 
+#ifdef CONFIG_COMPAT
+/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
+#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4, struct compat_atm_iobuf)
+#endif
+
 static int svc_create(struct net *net, struct socket *sock, int protocol,
 		      int kern);
 
-- 
2.4.10

[PATCH 04/13] Always expose MAP_UNINITIALIZED to userspace

[Palmer Dabbelt]

This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
userspace wouldn't actually ever see it be non-zero.  While I had
originally hoped to avoid hiding it, it looks like this conflicts with
MAP_HUGE_SHIFT so I think it's safer to just keep this 0.

Architectures that want to define this can still override it.  In
fact, the Xtensa port already overrides it in a very similar manner to
the previously broken one (but due to lots of conflicting opinions on
how to solve this correctly, I'm just taking the easy way out and
letting their arch maintainers deal with it -- sorry).

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/mman-common.h | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h
index ddc3b36..0ce2a13 100644
--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h
@@ -19,9 +19,7 @@
 #define MAP_TYPE	0x0f		/* Mask for type of mapping */
 #define MAP_FIXED	0x10		/* Interpret addr exactly */
 #define MAP_ANONYMOUS	0x20		/* don't use a file */
-#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED
-# define MAP_UNINITIALIZED 0x4000000	/* For anonymous mmap, memory could be uninitialized */
-#else
+#ifndef MAP_UNINITIALIZED
 # define MAP_UNINITIALIZED 0x0		/* Don't support this flag */
 #endif
 
-- 
2.4.10

[PATCH 05/13] Split FDPIC "struct elf_prstatus" to "struct elf_fdpic_prstatus"

[Palmer Dabbelt]

This is a pretty big change that I haven't tested any, which worries
me a lot.  The general idea here is that "struct elf_prstatus" can be
visible to userspace (from <linux/ptrace.h>)

  "
   Generic ptrace interface that exports the architecture specific
   regsets using the corresponding NT_* types (which are also used in
   the core dump).  Please note that the NT_PRSTATUS note type in a
   core dump contains a full 'struct elf_prstatus'. But the
   user_regset for NT_PRSTATUS contains just the elf_gregset_t that is
   the pr_reg field of 'struct elf_prstatus'. For all the other
   user_regset flavors, the user_regset layout and the ELF core dump
   note payload are exactly the same layout.
  "

so it shouldn't have an "#ifdef CONFIG_" in there.

This splits the structure into two different structures, one still
named "struct elf_prstatus", and one for ELF FDPIC that is named
"struct elf_fdpic_prstatus" -- the idea here is that most users are
standard ELF, so that's the name that didn't change.

I tried to fix all the users of "struct elf_prstatus" that should now
be using "struct elf_fdpic_prstatus".  The only testing I did here was
to build a Blackfin defconfig with "struct elf_prstatus" not defined,
and to build an x86 defconfig with "struct elf_fdpic_prstatus" not
defined.

Note that this fails checkpatch.pl with a complaint about wanting open
braces on the same line as struct definitions.  The existing struct
definitions in this file have the brace a line afterwards, so I'm
going to leave this alone.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/binfmt_elf_fdpic.c        |  6 +++---
 fs/proc/kcore.c              | 16 ++++++++++++++++
 include/linux/kexec.h        |  4 ++++
 include/uapi/linux/elfcore.h | 37 +++++++++++++++++++++++++++++++++++--
 kernel/kexec_core.c          |  4 ++++
 5 files changed, 62 insertions(+), 5 deletions(-)

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index d3634bf..587bf04 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1323,7 +1323,7 @@ static inline void fill_note(struct memelfnote *note, const char *name, int type
  * fill up all the fields in prstatus from the given task struct, except
  * registers which need to be filled up separately.
  */
-static void fill_prstatus(struct elf_prstatus *prstatus,
+static void fill_prstatus(struct elf_fdpic_prstatus *prstatus,
 			  struct task_struct *p, long signr)
 {
 	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
@@ -1406,7 +1406,7 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
 struct elf_thread_status
 {
 	struct list_head list;
-	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
+	struct elf_fdpic_prstatus prstatus;	/* NT_PRSTATUS */
 	elf_fpregset_t fpu;		/* NT_PRFPREG */
 	struct task_struct *thread;
 #ifdef ELF_CORE_COPY_XFPREGS
@@ -1539,7 +1539,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 	loff_t offset = 0, dataoff;
 	int numnote;
 	struct memelfnote *notes = NULL;
-	struct elf_prstatus *prstatus = NULL;	/* NT_PRSTATUS */
+	struct elf_fdpic_prstatus *prstatus = NULL;	/* NT_PRSTATUS */
 	struct elf_prpsinfo *psinfo = NULL;	/* NT_PRPSINFO */
  	LIST_HEAD(thread_list);
  	struct list_head *t;
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 92e6726..b1edd77e 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -90,7 +90,11 @@ static size_t get_kcore_size(int *nphdr, size_t *elf_buflen)
 			(*nphdr + 2)*sizeof(struct elf_phdr) + 
 			3 * ((sizeof(struct elf_note)) +
 			     roundup(sizeof(CORE_STR), 4)) +
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+			roundup(sizeof(struct elf_fdpic_prstatus), 4) +
+#else
 			roundup(sizeof(struct elf_prstatus), 4) +
+#endif
 			roundup(sizeof(struct elf_prpsinfo), 4) +
 			roundup(arch_task_struct_size, 4);
 	*elf_buflen = PAGE_ALIGN(*elf_buflen);
@@ -318,7 +322,11 @@ static char *storenote(struct memelfnote *men, char *bufp)
  */
 static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff)
 {
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	struct elf_fdpic_prstatus prstatus;	/* NT_PRSTATUS */
+#else
 	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
+#endif
 	struct elf_prpsinfo prpsinfo;	/* NT_PRPSINFO */
 	struct elf_phdr *nhdr, *phdr;
 	struct elfhdr *elf;
@@ -387,10 +395,18 @@ static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff)
 	/* set up the process status */
 	notes[0].name = CORE_STR;
 	notes[0].type = NT_PRSTATUS;
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	notes[0].datasz = sizeof(struct elf_fdpic_prstatus);
+#else
 	notes[0].datasz = sizeof(struct elf_prstatus);
+#endif
 	notes[0].data = &prstatus;
 
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	memset(&prstatus, 0, sizeof(struct elf_fdpic_prstatus));
+#else
 	memset(&prstatus, 0, sizeof(struct elf_prstatus));
+#endif
 
 	nhdr->p_filesz	= notesize(&notes[0]);
 	bufp = storenote(&notes[0], bufp);
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index d140b1e..d9196cc 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -63,7 +63,11 @@
 #define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
 #define KEXEC_CORE_NOTE_NAME "CORE"
 #define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+#define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_fdpic_prstatus), 4)
+#else
 #define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
+#endif
 /*
  * The per-cpu notes area is a list of notes terminated by a "NULL"
  * note header.  For kdump, the code in vmcore.c runs in the context
diff --git a/include/uapi/linux/elfcore.h b/include/uapi/linux/elfcore.h
index 569737c..697c52d 100644
--- a/include/uapi/linux/elfcore.h
+++ b/include/uapi/linux/elfcore.h
@@ -60,7 +60,40 @@ struct elf_prstatus
 	long	pr_instr;		/* Current instruction */
 #endif
 	elf_gregset_t pr_reg;	/* GP registers */
-#ifdef CONFIG_BINFMT_ELF_FDPIC
+	int pr_fpvalid;		/* True if math co-processor being used.  */
+};
+
+/* Architectures that set CONFIG_BINFMT_ELF_FDPIC use this instead of
+ * "struct elf_prstatus".
+ */
+struct elf_fdpic_prstatus
+{
+#if 0
+	long	pr_flags;	/* XXX Process flags */
+	short	pr_why;		/* XXX Reason for process halt */
+	short	pr_what;	/* XXX More detailed reason */
+#endif
+	struct elf_siginfo pr_info;	/* Info associated with signal */
+	short	pr_cursig;		/* Current signal */
+	unsigned long pr_sigpend;	/* Set of pending signals */
+	unsigned long pr_sighold;	/* Set of held signals */
+#if 0
+	struct sigaltstack pr_altstack;	/* Alternate stack info */
+	struct sigaction pr_action;	/* Signal action for current sig */
+#endif
+	pid_t	pr_pid;
+	pid_t	pr_ppid;
+	pid_t	pr_pgrp;
+	pid_t	pr_sid;
+	struct timeval pr_utime;	/* User time */
+	struct timeval pr_stime;	/* System time */
+	struct timeval pr_cutime;	/* Cumulative user time */
+	struct timeval pr_cstime;	/* Cumulative system time */
+#if 0
+	long	pr_instr;		/* Current instruction */
+#endif
+	elf_gregset_t pr_reg;	/* GP registers */
+
 	/* When using FDPIC, the loadmap addresses need to be communicated
 	 * to GDB in order for GDB to do the necessary relocations.  The
 	 * fields (below) used to communicate this information are placed
@@ -69,7 +102,7 @@ struct elf_prstatus
 	 */
 	unsigned long pr_exec_fdpic_loadmap;
 	unsigned long pr_interp_fdpic_loadmap;
-#endif
+
 	int pr_fpvalid;		/* True if math co-processor being used.  */
 };
 
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 201b453..8d2fc70 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -977,7 +977,11 @@ static void final_note(u32 *buf)
 
 void crash_save_cpu(struct pt_regs *regs, int cpu)
 {
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	struct elf_fdpic_prstatus prstatus;
+#else
 	struct elf_prstatus prstatus;
+#endif
 	u32 *buf;
 
 	if ((cpu < 0) || (cpu >= nr_cpu_ids))
-- 
2.4.10

[PATCH 06/13] Move ep_take_care_of_epollwakeup() to fs/eventpoll.c

[Palmer Dabbelt]

This doesn't make any sense to expose to userspace, so it's been moved
to the one user.  This was introduced by commit 95f19f658ce1 ("epoll:
drop EPOLLWAKEUP if PM_SLEEP is disabled").

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/eventpoll.c                 | 13 +++++++++++++
 include/uapi/linux/eventpoll.h | 12 ------------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 1e009ca..aadee3d 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1812,6 +1812,19 @@ SYSCALL_DEFINE1(epoll_create, int, size)
 	return sys_epoll_create1(0);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
+		epev->events &= ~EPOLLWAKEUP;
+}
+#else
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	epev->events &= ~EPOLLWAKEUP;
+}
+#endif
+
 /*
  * The following function implements the controller interface for
  * the eventpoll file that enables the insertion/removal/change of
diff --git a/include/uapi/linux/eventpoll.h b/include/uapi/linux/eventpoll.h
index bc81fb2..7850373 100644
--- a/include/uapi/linux/eventpoll.h
+++ b/include/uapi/linux/eventpoll.h
@@ -61,16 +61,4 @@ struct epoll_event {
 	__u64 data;
 } EPOLL_PACKED;
 
-#ifdef CONFIG_PM_SLEEP
-static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
-{
-	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
-		epev->events &= ~EPOLLWAKEUP;
-}
-#else
-static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
-{
-	epev->events &= ~EPOLLWAKEUP;
-}
-#endif
 #endif /* _UAPI_LINUX_EVENTPOLL_H */
-- 
2.4.10

[PATCH 07/13] Make FB_BACKLIGHT_{LEVELS,MAX} always visible

[Palmer Dabbelt]

Nothing else in the kernel defines this, and this header is visible to
userspace.  Rather than hiding it in an #ifdef, I think it's sane to
just make this visible to userspace.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/fb.h | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/include/uapi/linux/fb.h b/include/uapi/linux/fb.h
index fb795c3..8926f13 100644
--- a/include/uapi/linux/fb.h
+++ b/include/uapi/linux/fb.h
@@ -392,11 +392,8 @@ struct fb_cursor {
 	struct fb_image	image;	/* Cursor image */
 };
 
-#ifdef CONFIG_FB_BACKLIGHT
 /* Settings for the generic backlight code */
 #define FB_BACKLIGHT_LEVELS	128
 #define FB_BACKLIGHT_MAX	0xFF
-#endif
-
 
 #endif /* _UAPI_LINUX_FB_H */
-- 
2.4.10

[PATCH 08/13] Move MAX_SHARED_LIBS to fs/binfmt_flat.c

[Palmer Dabbelt]

I'm not sure what this is, but it doesn't feel like something that
should be exposed to userspace here.  I'm assuming this file was
exposed for the structure in it, which doesn't depend on
MAX_SHARED_LIBS.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/binfmt_flat.c          | 6 ++++++
 include/uapi/linux/flat.h | 6 ------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index f723cd3..e89fb43 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -72,6 +72,12 @@
 #define RELOC_FAILED 0xff00ff01		/* Relocation incorrect somewhere */
 #define UNLOADED_LIB 0x7ff000ff		/* Placeholder for unused library */
 
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+#define	MAX_SHARED_LIBS			(4)
+#else
+#define	MAX_SHARED_LIBS			(1)
+#endif
+
 struct lib_info {
 	struct {
 		unsigned long start_code;		/* Start of text segment */
diff --git a/include/uapi/linux/flat.h b/include/uapi/linux/flat.h
index 88cd6ba..1b177c7 100644
--- a/include/uapi/linux/flat.h
+++ b/include/uapi/linux/flat.h
@@ -13,12 +13,6 @@
 
 #define	FLAT_VERSION			0x00000004L
 
-#ifdef CONFIG_BINFMT_SHARED_FLAT
-#define	MAX_SHARED_LIBS			(4)
-#else
-#define	MAX_SHARED_LIBS			(1)
-#endif
-
 /*
  * To make everything easier to port and manage cross platform
  * development,  all fields are in network byte order.
-- 
2.4.10

[PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Palmer Dabbelt]

This has a "#ifdef CONFIG_*" that used to be exposed to userspace.

The names in here are so generic that I don't think it's a good idea
to expose them to userspace (or even the rest of the kernel).  Since
there's only one kernel user, it's been moved to that file.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/hw_breakpoint.h | 10 ----------
 kernel/events/hw_breakpoint.c      | 10 ++++++++++
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
index b04000a..7a6a5a7 100644
--- a/include/uapi/linux/hw_breakpoint.h
+++ b/include/uapi/linux/hw_breakpoint.h
@@ -17,14 +17,4 @@ enum {
 	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
 };
 
-enum bp_type_idx {
-	TYPE_INST 	= 0,
-#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
-	TYPE_DATA	= 0,
-#else
-	TYPE_DATA	= 1,
-#endif
-	TYPE_MAX
-};
-
 #endif /* _UAPI_LINUX_HW_BREAKPOINT_H */
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index 92ce5f4..5ad117e 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -58,6 +58,16 @@ struct bp_cpuinfo {
 	unsigned int	flexible; /* XXX: placeholder, see fetch_this_slot() */
 };
 
+enum bp_type_idx {
+	TYPE_INST	= 0,
+#if defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
+	TYPE_DATA	= 0,
+#else
+	TYPE_DATA	= 1,
+#endif
+	TYPE_MAX
+};
+
 static DEFINE_PER_CPU(struct bp_cpuinfo, bp_cpuinfo[TYPE_MAX]);
 static int nr_slots[TYPE_MAX];
 
-- 
2.4.10

[PATCH 10/13] Move USE_WCACHING to drivers/block/pktcdvd.c

[Palmer Dabbelt]

I don't think this was ever intended to be exposed to userspace, but
it did require an "#ifdef CONFIG_*".  Since the name is kind of
generic and was only used in one place, I've moved the definition to
the one user.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 drivers/block/pktcdvd.c      | 11 +++++++++++
 include/uapi/linux/pktcdvd.h | 11 -----------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 7be2375..18d2d05 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -90,6 +90,17 @@ do {									\
 
 #define MAX_SPEED 0xffff
 
+/*
+ * use drive write caching -- we need deferred error handling to be
+ * able to successfully recover with this option (drive will return good
+ * status as soon as the cdb is validated).
+ */
+#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
+#define USE_WCACHING		1
+#else
+#define USE_WCACHING		0
+#endif
+
 static DEFINE_MUTEX(pktcdvd_mutex);
 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
 static struct proc_dir_entry *pkt_proc;
diff --git a/include/uapi/linux/pktcdvd.h b/include/uapi/linux/pktcdvd.h
index 2640b9d..05c2bee 100644
--- a/include/uapi/linux/pktcdvd.h
+++ b/include/uapi/linux/pktcdvd.h
@@ -29,17 +29,6 @@
 #define PACKET_WAIT_TIME	(HZ * 5 / 1000)
 
 /*
- * use drive write caching -- we need deferred error handling to be
- * able to successfully recover with this option (drive will return good
- * status as soon as the cdb is validated).
- */
-#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
-#define USE_WCACHING		1
-#else
-#define USE_WCACHING		0
-#endif
-
-/*
  * No user-servicable parts beyond this point ->
  */
 
-- 
2.4.10

[PATCH 11/13] Always define MAX_RAW_MINORS as 2**20 in userspace

[Palmer Dabbelt]

While I don't think this was ever meant to be exposed to userspace, if
anyone is using it then this will at least provide a correct (if
unlikely) definition.

MAX_RAW_MINORS used to be used in the kernel, where it's been replaced
with CONFIG_MAX_RAW_MINORS.

Note that there's a checkpatch.pl warning about a split config string
here, but I've left that alone.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 drivers/char/raw.c       | 7 ++++---
 include/uapi/linux/raw.h | 2 +-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index 60316fb..362d7a6 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -36,7 +36,7 @@ static struct raw_device_data *raw_devices;
 static DEFINE_MUTEX(raw_mutex);
 static const struct file_operations raw_ctl_fops; /* forward declaration */
 
-static int max_raw_minors = MAX_RAW_MINORS;
+static int max_raw_minors = CONFIG_MAX_RAW_MINORS;
 
 module_param(max_raw_minors, int, 0);
 MODULE_PARM_DESC(max_raw_minors, "Maximum number of raw devices (1-65536)");
@@ -317,8 +317,9 @@ static int __init raw_init(void)
 
 	if (max_raw_minors < 1 || max_raw_minors > 65536) {
 		printk(KERN_WARNING "raw: invalid max_raw_minors (must be"
-			" between 1 and 65536), using %d\n", MAX_RAW_MINORS);
-		max_raw_minors = MAX_RAW_MINORS;
+			" between 1 and 65536), using %d\n",
+		       CONFIG_MAX_RAW_MINORS);
+		max_raw_minors = CONFIG_MAX_RAW_MINORS;
 	}
 
 	raw_devices = vzalloc(sizeof(struct raw_device_data) * max_raw_minors);
diff --git a/include/uapi/linux/raw.h b/include/uapi/linux/raw.h
index 62d543e..f3d009b 100644
--- a/include/uapi/linux/raw.h
+++ b/include/uapi/linux/raw.h
@@ -13,6 +13,6 @@ struct raw_config_request
 	__u64	block_minor;
 };
 
-#define MAX_RAW_MINORS CONFIG_MAX_RAW_DEVS
+#define MAX_RAW_MINORS (1 << 20)
 
 #endif /* __LINUX_RAW_H */
-- 
2.4.10

[PATCH 12/13] Remove AT_VECTOR_SIZE_ARCH on x86

[Palmer Dabbelt]

It looks like there aren't actually users of this macro anywhere:

 * The kernel doesn't use it on x86 because we don't suppor ELF FDPIC.

 * The only Google results point to LMKL patches, both the one that
   wrote this (from 2010) and my patch to hide it behind __KERNEL__.

 * I grep'd through all the source tarballs on my machine, and the
   only packages that matched were the kernel and crui (which copied a
   PPC kernel header).

Since I'm not sure how to actually provide the right answer (if I
understand correctly, CONFIG_IA32_EMULATION is not __i386__), the only
thing I can think of to do is to just remove the definition.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 arch/x86/include/uapi/asm/auxvec.h | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/x86/include/uapi/asm/auxvec.h b/arch/x86/include/uapi/asm/auxvec.h
index 77203ac..1316b4c 100644
--- a/arch/x86/include/uapi/asm/auxvec.h
+++ b/arch/x86/include/uapi/asm/auxvec.h
@@ -9,11 +9,4 @@
 #endif
 #define AT_SYSINFO_EHDR		33
 
-/* entries in ARCH_DLINFO: */
-#if defined(CONFIG_IA32_EMULATION) || !defined(CONFIG_X86_64)
-# define AT_VECTOR_SIZE_ARCH 2
-#else /* else it's non-compat x86-64 */
-# define AT_VECTOR_SIZE_ARCH 1
-#endif
-
 #endif /* _ASM_X86_AUXVEC_H */
-- 
2.4.10

[PATCH 13/13] Re-enable and clean up "check_config()" in headers_check.pl

[Palmer Dabbelt]

I recently got bit by a CONFIG_ in userspace bug.  This has apparently
happened before, but the check got disabled for triggering too much.
In order to reduce false positives, I added some hueristics to avoid
detecting comments.

Since these tests all pass, I've now re-enabled them.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 scripts/headers_check.pl | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/scripts/headers_check.pl b/scripts/headers_check.pl
index 62320f9..1634b51 100755
--- a/scripts/headers_check.pl
+++ b/scripts/headers_check.pl
@@ -27,6 +27,7 @@ my $ret = 0;
 my $line;
 my $lineno = 0;
 my $filename;
+my $check_config_in_multiline_comment = 0;
 
 foreach my $file (@files) {
 	$filename = $file;
@@ -40,7 +41,7 @@ foreach my $file (@files) {
 		&check_asm_types();
 		&check_sizetypes();
 		&check_declarations();
-		# Dropped for now. Too much noise &check_config();
+		&check_config();
 	}
 	close $fh;
 }
@@ -78,7 +79,21 @@ sub check_declarations
 
 sub check_config
 {
-	if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
+	my $nocomments = $line;
+	$nocomments =~ s/\/\*.*\*\///; # Remove ANSI-style comments (/* to */)
+	$nocomments =~ s/\/\/.*//;     # Remove C99-style comments (// to EOL)
+
+	# Check to see if we're within a multiline comment, and if so
+	# just remove the whole line.  I tried matching on '^ * ', but
+	# there's one header that doesn't prepend multi-line comments
+	# with * so that won't work.
+	if ($nocomments =~ m/\/\*/) { $check_config_in_multiline_comment = 1; }
+	if ($nocomments =~ m/\*\//) { $check_config_in_multiline_comment = 0; }
+	if ($check_config_in_multiline_comment == 1) { $nocomments = "" }
+
+	# Check to see if there is something that looks like CONFIG_
+	# inside a userspace-accessible header file and if so, print that out.
+	if ($nocomments =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
 		printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n";
 	}
 }
-- 
2.4.10

Re: [PATCH 11/13] Always define MAX_RAW_MINORS as 2**20 in userspace

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1359 bytes --]

Hi Palmer,

[auto build test ERROR on v4.3-rc7]
[also ERROR on: next-20151103]

url:    https://github.com/0day-ci/linux/commits/Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
base:   https://github.com/0day-ci/linux Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
config: x86_64-randconfig-x014-11022153 (attached as .config)
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

>> drivers/char/raw.c:39:29: error: 'CONFIG_MAX_RAW_MINORS' undeclared here (not in a function)
    static int max_raw_minors = CONFIG_MAX_RAW_MINORS;
                                ^

vim +/CONFIG_MAX_RAW_MINORS +39 drivers/char/raw.c

    33	
    34	static struct class *raw_class;
    35	static struct raw_device_data *raw_devices;
    36	static DEFINE_MUTEX(raw_mutex);
    37	static const struct file_operations raw_ctl_fops; /* forward declaration */
    38	
  > 39	static int max_raw_minors = CONFIG_MAX_RAW_MINORS;
    40	
    41	module_param(max_raw_minors, int, 0);
    42	MODULE_PARM_DESC(max_raw_minors, "Maximum number of raw devices (1-65536)");

---
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[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 21634 bytes --]

Re: [PATCH 13/13] Re-enable and clean up "check_config()" in headers_check.pl

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 2466 bytes --]

Hi Palmer,

[auto build test WARNING on v4.3-rc7]
[also WARNING on: next-20151103]

url:    https://github.com/0day-ci/linux/commits/Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
base:   https://github.com/0day-ci/linux Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
config: blackfin-TCM-BF537_defconfig (attached as .config)
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=blackfin 

All warnings (new ones prefixed by >>):

>> ./usr/include/asm/fixed_code.h:14: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:15: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:18: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:20: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:22: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:24: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:25: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:26: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:27: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:28: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:29: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:30: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:32: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:34: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid
   ./usr/include/asm/fixed_code.h:36: leaks CONFIG_PHY_RAM_BASE_ADDRESS to userspace where it is not valid

---
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[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 10070 bytes --]

Re: [PATCH 13/13] Re-enable and clean up "check_config()" in headers_check.pl

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 953 bytes --]

Hi Palmer,

[auto build test WARNING on v4.3-rc7]
[also WARNING on: next-20151103]

url:    https://github.com/0day-ci/linux/commits/Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
base:   https://github.com/0day-ci/linux Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
config: alpha-defconfig (attached as .config)
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=alpha 

All warnings (new ones prefixed by >>):

>> ./usr/include/asm/setup.h:16: leaks CONFIG_ALPHA_LEGACY_START_ADDRESS to userspace where it is not valid

---
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[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 11535 bytes --]

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 2149 bytes --]

Hi Palmer,

[auto build test ERROR on v4.3-rc7]
[also ERROR on: next-20151103]

url:    https://github.com/0day-ci/linux/commits/Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
base:   https://github.com/0day-ci/linux Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
config: powerpc-defconfig (attached as .config)
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=powerpc 

All errors (new ones prefixed by >>):

   arch/powerpc/kernel/hw_breakpoint.c: In function 'hw_breakpoint_slots':
>> arch/powerpc/kernel/hw_breakpoint.c:49:14: error: 'TYPE_DATA' undeclared (first use in this function)
     if (type == TYPE_DATA)
                 ^
   arch/powerpc/kernel/hw_breakpoint.c:49:14: note: each undeclared identifier is reported only once for each function it appears in

vim +/TYPE_DATA +49 arch/powerpc/kernel/hw_breakpoint.c

5aae8a53 K.Prasad       2010-06-15  43  
5aae8a53 K.Prasad       2010-06-15  44  /*
d09ec738 Paul Mackerras 2010-06-29  45   * Returns total number of data or instruction breakpoints available.
d09ec738 Paul Mackerras 2010-06-29  46   */
d09ec738 Paul Mackerras 2010-06-29  47  int hw_breakpoint_slots(int type)
d09ec738 Paul Mackerras 2010-06-29  48  {
d09ec738 Paul Mackerras 2010-06-29 @49  	if (type == TYPE_DATA)
d09ec738 Paul Mackerras 2010-06-29  50  		return HBP_NUM;
d09ec738 Paul Mackerras 2010-06-29  51  	return 0;		/* no instruction breakpoints available */
d09ec738 Paul Mackerras 2010-06-29  52  }

:::::: The code at line 49 was first introduced by commit
:::::: d09ec7387184eba9e3030496f0451204090ff610 powerpc, hw_breakpoint: Tell generic code we have no instruction breakpoints

:::::: TO: Paul Mackerras <paulus@samba.org>
:::::: CC: Paul Mackerras <paulus@samba.org>

---
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[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 21538 bytes --]

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 2896 bytes --]

Hi Palmer,

[auto build test ERROR on v4.3-rc7]
[also ERROR on: next-20151103]

url:    https://github.com/0day-ci/linux/commits/Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
base:   https://github.com/0day-ci/linux Palmer-Dabbelt/Remove-ifdef-CONFIG_64BIT-from-all-asm-generic-fcntl-h/20151104-035501
config: arm-socfpga_defconfig (attached as .config)
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=arm 

All errors (new ones prefixed by >>):

   arch/arm/kernel/ptrace.c: In function 'ptrace_get_hbp_resource_info':
>> arch/arm/kernel/ptrace.c:440:33: error: 'TYPE_INST' undeclared (first use in this function)
     num_brps = hw_breakpoint_slots(TYPE_INST);
                                    ^
   arch/arm/kernel/ptrace.c:440:33: note: each undeclared identifier is reported only once for each function it appears in
>> arch/arm/kernel/ptrace.c:441:33: error: 'TYPE_DATA' undeclared (first use in this function)
     num_wrps = hw_breakpoint_slots(TYPE_DATA);
                                    ^
--
   arch/arm/kernel/hw_breakpoint.c: In function 'hw_breakpoint_slots':
>> arch/arm/kernel/hw_breakpoint.c:290:7: error: 'TYPE_INST' undeclared (first use in this function)
     case TYPE_INST:
          ^
   arch/arm/kernel/hw_breakpoint.c:290:7: note: each undeclared identifier is reported only once for each function it appears in
>> arch/arm/kernel/hw_breakpoint.c:292:7: error: 'TYPE_DATA' undeclared (first use in this function)
     case TYPE_DATA:
          ^

vim +/TYPE_INST +440 arch/arm/kernel/ptrace.c

864232fa Will Deacon 2010-09-03  434  
864232fa Will Deacon 2010-09-03  435  static u32 ptrace_get_hbp_resource_info(void)
864232fa Will Deacon 2010-09-03  436  {
864232fa Will Deacon 2010-09-03  437  	u8 num_brps, num_wrps, debug_arch, wp_len;
864232fa Will Deacon 2010-09-03  438  	u32 reg = 0;
864232fa Will Deacon 2010-09-03  439  
864232fa Will Deacon 2010-09-03 @440  	num_brps	= hw_breakpoint_slots(TYPE_INST);
864232fa Will Deacon 2010-09-03 @441  	num_wrps	= hw_breakpoint_slots(TYPE_DATA);
864232fa Will Deacon 2010-09-03  442  	debug_arch	= arch_get_debug_arch();
864232fa Will Deacon 2010-09-03  443  	wp_len		= arch_get_max_wp_len();
864232fa Will Deacon 2010-09-03  444  

:::::: The code at line 440 was first introduced by commit
:::::: 864232fa1a2f8dfe003438ef0851a56722740f3e ARM: 6357/1: hw-breakpoint: add new ptrace requests for hw-breakpoint interaction

:::::: TO: Will Deacon <will.deacon@arm.com>
:::::: CC: Russell King <rmk+kernel@arm.linux.org.uk>

---
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[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 15319 bytes --]

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Peter Zijlstra]

On Tue, Nov 03, 2015 at 11:46:30AM -0800, Palmer Dabbelt wrote:
> This has a "#ifdef CONFIG_*" that used to be exposed to userspace.
> 
> The names in here are so generic that I don't think it's a good idea
> to expose them to userspace (or even the rest of the kernel).  Since
> there's only one kernel user, it's been moved to that file.
> 
> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>

Assuming you want to keep all these patches together in a tree or so.
Let me know if you want me to take this patch.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Peter Zijlstra]

On Wed, Nov 04, 2015 at 12:41:06PM +0100, Peter Zijlstra wrote:
> On Tue, Nov 03, 2015 at 11:46:30AM -0800, Palmer Dabbelt wrote:
> > This has a "#ifdef CONFIG_*" that used to be exposed to userspace.
> > 
> > The names in here are so generic that I don't think it's a good idea
> > to expose them to userspace (or even the rest of the kernel).  Since
> > there's only one kernel user, it's been moved to that file.
> > 
> > Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
> > Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
> > Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
> 
> Assuming you want to keep all these patches together in a tree or so.
> Let me know if you want me to take this patch.
> 
> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Ah, build-bot finds your change is broken and you didn't grep right. It
is used in more places.

How about moving it to include/linux/hw_breakpoint.h, instead of having
it in the uapi crud?

Re: [PATCH 09/13] Move bp_type_idx to kernel/event/hw_breakpoint.c

[Palmer Dabbelt]

On Wed, 04 Nov 2015 04:21:51 PST (-0800), peterz@infradead.org wrote:
> On Wed, Nov 04, 2015 at 12:41:06PM +0100, Peter Zijlstra wrote:
>> On Tue, Nov 03, 2015 at 11:46:30AM -0800, Palmer Dabbelt wrote:
>> > This has a "#ifdef CONFIG_*" that used to be exposed to userspace.
>> >
>> > The names in here are so generic that I don't think it's a good idea
>> > to expose them to userspace (or even the rest of the kernel).  Since
>> > there's only one kernel user, it's been moved to that file.
>> >
>> > Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
>> > Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
>> > Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
>>
>> Assuming you want to keep all these patches together in a tree or so.
>> Let me know if you want me to take this patch.

Well, the plan was to try to get the whole patch set all upstream together.
I'd prefer that, because it'll be easier to make sure everything gets in before
the last checker patch.  Since it touches so many different places I'd be OK
with doing it peicemeal.

I'm kind of new to this whole process: do you think someone is likely to take
this patch set all together?

>> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
>
> Ah, build-bot finds your change is broken and you didn't grep right. It
> is used in more places.

Sorry about that, I must have mis-grep'd.  I guess that's what the build-bot is
for :).

> How about moving it to include/linux/hw_breakpoint.h, instead of having
> it in the uapi crud?

Yep, that makes sense.

I'm going to re-submit a v5 of this patch set, since there was also a missing
patch for blackfin that the buildbot found.

[PATCH v5] Remove #ifdef CONFIG_* from all userspace headers

[Palmer Dabbelt]

I think this should _actually_ be ready to go this time, the buildbot found
some errors in arches that I didn't test for.

Changes since v4 (<1446579994-9937-1-git-send-email-palmer@dabbelt.com>)

 * #9 was changed to work on arm by moving the enum to an in-kernel header
   file.

 * #13 was added, this fixes a problem on blackfin.

Changes since v3 (<1442271047-4908-1-git-send-email-palmer@dabbelt.com>)

 * #4 is very different: rather than defining a canonical value for
   MAP_UNINITIALIZED, it just punts on the problem and lets arch maintainers
   deal with it.  There's still an #ifndef MAP_UNINITIALIZED in there, but that
   shouldn't get triggered by anything because the arch headers should set it
   to whatever they actually want.

 * #11 defines MAX_RAW_MINORS to 2^20 instead of 2^16.

 * #13 moves the variable around a bit so it gets initialized.  I forgot I was
   in perl and not C :).

Changes since v2 (<1441832902-28993-1-git-send-email-palmer@dabbelt.com>)

 * Patch set renamed.

 * #2 is rewritten to use sys_ni.c instead of an #ifdef

 * #3, #6, #8, #9, #10, and #11 no longer use "#ifdef __KERNEL__" but
   have instead moved the offending lines to the correct, kernel-only
   files.

 * #4 has been rewritten to always define MAP_UNINITIALIZED to
   non-zero, rather than defining it to zero when in userspace.

 * #5 got a whole lot longer -- rather than just always hiding these
   fields from userspace, there is now a second "struct
   elf_fdpic_prstatus" structure.  This should allow userspace to
   parse core dumps correctly.

 * Rebased onto 9c488de24f7264f08d341024bffdd637b4d04c96.

Changes since v1 (<1441152610-22566-1-git-send-email-palmer@dabbelt.com>)

 * All patches but #1 were added.

[PATCH 01/14] Remove #ifdef CONFIG_64BIT from all asm-generic/fcntl.h

[Palmer Dabbelt]

When working on the RISC-V port I noticed that F_SETLK64 was being
defined on our 64-bit platform, despite our port being so new that
we've only ever had the 64-bit file ops.  Since there's not compat
layer for these, this causes fcntl to bail out.

It turns out that one of the ways in with F_SETLK64 was being defined
(there's some more in glibc, but that's a whole different story... :))
is the result of CONFIG_64BIT showing up in this user-visible header.
<asm-generic/bitsperlong.h> confirms this isn't sane, so I replaced it
with a __BITS_PER_LONG check.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
---
 include/uapi/asm-generic/fcntl.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
index e063eff..14a5c82 100644
--- a/include/uapi/asm-generic/fcntl.h
+++ b/include/uapi/asm-generic/fcntl.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_GENERIC_FCNTL_H
 #define _ASM_GENERIC_FCNTL_H
 
+#include <asm/bitsperlong.h>
 #include <linux/types.h>
 
 /*
@@ -115,7 +116,7 @@
 #define F_GETSIG	11	/* for sockets. */
 #endif
 
-#ifndef CONFIG_64BIT
+#if (__BITS_PER_LONG == 32)
 #ifndef F_GETLK64
 #define F_GETLK64	12	/*  using 'struct flock64' */
 #define F_SETLK64	13
-- 
2.4.10

[PATCH 02/14] Use sys_ni.c instead of #ifdef to disable fork on CONFIG_NOMMU

[Palmer Dabbelt]

I think this change actually doesn't do anything: __NR_fork was still
being defined either way, and on my machine fork() in <unistd.h> comes
from libc.

This just moves to the standard mechanism for defining syscalls that
aren't implemented instead, which has the side-effect of no longer
having an #ifdef CONFIG_* in a user-visible header.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/unistd.h | 4 ----
 kernel/sys_ni.c                   | 1 +
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 1324b02..9a95912 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -871,11 +871,7 @@ __SYSCALL(__NR_uselib, sys_uselib)
 __SYSCALL(__NR__sysctl, sys_sysctl)
 
 #define __NR_fork 1079
-#ifdef CONFIG_MMU
 __SYSCALL(__NR_fork, sys_fork)
-#else
-__SYSCALL(__NR_fork, sys_ni_syscall)
-#endif /* CONFIG_MMU */
 
 #undef __NR_syscalls
 #define __NR_syscalls (__NR_fork+1)
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 0623787..e251b30 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -174,6 +174,7 @@ cond_syscall(sys_setfsuid);
 cond_syscall(sys_setfsgid);
 cond_syscall(sys_capget);
 cond_syscall(sys_capset);
+cond_syscall(sys_fork);
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read);
-- 
2.4.10

[PATCH 03/14] Move COMPAT_ATM_ADDPARTY to net/atm/svc.c

[Palmer Dabbelt]

This used to be behind an #ifdef COMPAT_COMPAT, so most of userspace
wouldn't have seen the definition before.  Unfortunately this header
file became visible to userspace, so the definition has instead been
moved to net/atm/svc.c (the only user).

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/atmdev.h | 4 ----
 net/atm/svc.c               | 5 +++++
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/atmdev.h b/include/uapi/linux/atmdev.h
index 93e0ec0..3dcec70 100644
--- a/include/uapi/linux/atmdev.h
+++ b/include/uapi/linux/atmdev.h
@@ -100,10 +100,6 @@ struct atm_dev_stats {
 					/* use backend to make new if */
 #define ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct atm_iobuf)
  					/* add party to p2mp call */
-#ifdef CONFIG_COMPAT
-/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
-#define COMPAT_ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct compat_atm_iobuf)
-#endif
 #define ATM_DROPPARTY 	_IOW('a', ATMIOC_SPECIAL+5,int)
 					/* drop party from p2mp call */
 
diff --git a/net/atm/svc.c b/net/atm/svc.c
index 3fa0a9e..9e2e6ef 100644
--- a/net/atm/svc.c
+++ b/net/atm/svc.c
@@ -27,6 +27,11 @@
 #include "signaling.h"
 #include "addr.h"
 
+#ifdef CONFIG_COMPAT
+/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
+#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4, struct compat_atm_iobuf)
+#endif
+
 static int svc_create(struct net *net, struct socket *sock, int protocol,
 		      int kern);
 
-- 
2.4.10

[PATCH 04/14] Always expose MAP_UNINITIALIZED to userspace

[Palmer Dabbelt]

This used to be hidden behind CONFIG_MMAP_ALLOW_UNINITIALIZED, so
userspace wouldn't actually ever see it be non-zero.  While I had
originally hoped to avoid hiding it, it looks like this conflicts with
MAP_HUGE_SHIFT so I think it's safer to just keep this 0.

Architectures that want to define this can still override it.  In
fact, the Xtensa port already overrides it in a very similar manner to
the previously broken one (but due to lots of conflicting opinions on
how to solve this correctly, I'm just taking the easy way out and
letting their arch maintainers deal with it -- sorry).

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/asm-generic/mman-common.h | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h
index a74dd84..25ca92c 100644
--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h
@@ -19,9 +19,7 @@
 #define MAP_TYPE	0x0f		/* Mask for type of mapping */
 #define MAP_FIXED	0x10		/* Interpret addr exactly */
 #define MAP_ANONYMOUS	0x20		/* don't use a file */
-#ifdef CONFIG_MMAP_ALLOW_UNINITIALIZED
-# define MAP_UNINITIALIZED 0x4000000	/* For anonymous mmap, memory could be uninitialized */
-#else
+#ifndef MAP_UNINITIALIZED
 # define MAP_UNINITIALIZED 0x0		/* Don't support this flag */
 #endif
 
-- 
2.4.10

[PATCH 05/14] Split FDPIC "struct elf_prstatus" to "struct elf_fdpic_prstatus"

[Palmer Dabbelt]

This is a pretty big change that I haven't tested any, which worries
me a lot.  The general idea here is that "struct elf_prstatus" can be
visible to userspace (from <linux/ptrace.h>)

  "
   Generic ptrace interface that exports the architecture specific
   regsets using the corresponding NT_* types (which are also used in
   the core dump).  Please note that the NT_PRSTATUS note type in a
   core dump contains a full 'struct elf_prstatus'. But the
   user_regset for NT_PRSTATUS contains just the elf_gregset_t that is
   the pr_reg field of 'struct elf_prstatus'. For all the other
   user_regset flavors, the user_regset layout and the ELF core dump
   note payload are exactly the same layout.
  "

so it shouldn't have an "#ifdef CONFIG_" in there.

This splits the structure into two different structures, one still
named "struct elf_prstatus", and one for ELF FDPIC that is named
"struct elf_fdpic_prstatus" -- the idea here is that most users are
standard ELF, so that's the name that didn't change.

I tried to fix all the users of "struct elf_prstatus" that should now
be using "struct elf_fdpic_prstatus".  The only testing I did here was
to build a Blackfin defconfig with "struct elf_prstatus" not defined,
and to build an x86 defconfig with "struct elf_fdpic_prstatus" not
defined.

Note that this fails checkpatch.pl with a complaint about wanting open
braces on the same line as struct definitions.  The existing struct
definitions in this file have the brace a line afterwards, so I'm
going to leave this alone.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/binfmt_elf_fdpic.c        |  6 +++---
 fs/proc/kcore.c              | 16 ++++++++++++++++
 include/linux/kexec.h        |  4 ++++
 include/uapi/linux/elfcore.h | 37 +++++++++++++++++++++++++++++++++++--
 kernel/kexec_core.c          |  4 ++++
 5 files changed, 62 insertions(+), 5 deletions(-)

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index d3634bf..587bf04 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1323,7 +1323,7 @@ static inline void fill_note(struct memelfnote *note, const char *name, int type
  * fill up all the fields in prstatus from the given task struct, except
  * registers which need to be filled up separately.
  */
-static void fill_prstatus(struct elf_prstatus *prstatus,
+static void fill_prstatus(struct elf_fdpic_prstatus *prstatus,
 			  struct task_struct *p, long signr)
 {
 	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
@@ -1406,7 +1406,7 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
 struct elf_thread_status
 {
 	struct list_head list;
-	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
+	struct elf_fdpic_prstatus prstatus;	/* NT_PRSTATUS */
 	elf_fpregset_t fpu;		/* NT_PRFPREG */
 	struct task_struct *thread;
 #ifdef ELF_CORE_COPY_XFPREGS
@@ -1539,7 +1539,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 	loff_t offset = 0, dataoff;
 	int numnote;
 	struct memelfnote *notes = NULL;
-	struct elf_prstatus *prstatus = NULL;	/* NT_PRSTATUS */
+	struct elf_fdpic_prstatus *prstatus = NULL;	/* NT_PRSTATUS */
 	struct elf_prpsinfo *psinfo = NULL;	/* NT_PRPSINFO */
  	LIST_HEAD(thread_list);
  	struct list_head *t;
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 92e6726..b1edd77e 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -90,7 +90,11 @@ static size_t get_kcore_size(int *nphdr, size_t *elf_buflen)
 			(*nphdr + 2)*sizeof(struct elf_phdr) + 
 			3 * ((sizeof(struct elf_note)) +
 			     roundup(sizeof(CORE_STR), 4)) +
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+			roundup(sizeof(struct elf_fdpic_prstatus), 4) +
+#else
 			roundup(sizeof(struct elf_prstatus), 4) +
+#endif
 			roundup(sizeof(struct elf_prpsinfo), 4) +
 			roundup(arch_task_struct_size, 4);
 	*elf_buflen = PAGE_ALIGN(*elf_buflen);
@@ -318,7 +322,11 @@ static char *storenote(struct memelfnote *men, char *bufp)
  */
 static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff)
 {
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	struct elf_fdpic_prstatus prstatus;	/* NT_PRSTATUS */
+#else
 	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
+#endif
 	struct elf_prpsinfo prpsinfo;	/* NT_PRPSINFO */
 	struct elf_phdr *nhdr, *phdr;
 	struct elfhdr *elf;
@@ -387,10 +395,18 @@ static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff)
 	/* set up the process status */
 	notes[0].name = CORE_STR;
 	notes[0].type = NT_PRSTATUS;
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	notes[0].datasz = sizeof(struct elf_fdpic_prstatus);
+#else
 	notes[0].datasz = sizeof(struct elf_prstatus);
+#endif
 	notes[0].data = &prstatus;
 
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	memset(&prstatus, 0, sizeof(struct elf_fdpic_prstatus));
+#else
 	memset(&prstatus, 0, sizeof(struct elf_prstatus));
+#endif
 
 	nhdr->p_filesz	= notesize(&notes[0]);
 	bufp = storenote(&notes[0], bufp);
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index d140b1e..d9196cc 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -63,7 +63,11 @@
 #define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
 #define KEXEC_CORE_NOTE_NAME "CORE"
 #define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+#define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_fdpic_prstatus), 4)
+#else
 #define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
+#endif
 /*
  * The per-cpu notes area is a list of notes terminated by a "NULL"
  * note header.  For kdump, the code in vmcore.c runs in the context
diff --git a/include/uapi/linux/elfcore.h b/include/uapi/linux/elfcore.h
index 569737c..697c52d 100644
--- a/include/uapi/linux/elfcore.h
+++ b/include/uapi/linux/elfcore.h
@@ -60,7 +60,40 @@ struct elf_prstatus
 	long	pr_instr;		/* Current instruction */
 #endif
 	elf_gregset_t pr_reg;	/* GP registers */
-#ifdef CONFIG_BINFMT_ELF_FDPIC
+	int pr_fpvalid;		/* True if math co-processor being used.  */
+};
+
+/* Architectures that set CONFIG_BINFMT_ELF_FDPIC use this instead of
+ * "struct elf_prstatus".
+ */
+struct elf_fdpic_prstatus
+{
+#if 0
+	long	pr_flags;	/* XXX Process flags */
+	short	pr_why;		/* XXX Reason for process halt */
+	short	pr_what;	/* XXX More detailed reason */
+#endif
+	struct elf_siginfo pr_info;	/* Info associated with signal */
+	short	pr_cursig;		/* Current signal */
+	unsigned long pr_sigpend;	/* Set of pending signals */
+	unsigned long pr_sighold;	/* Set of held signals */
+#if 0
+	struct sigaltstack pr_altstack;	/* Alternate stack info */
+	struct sigaction pr_action;	/* Signal action for current sig */
+#endif
+	pid_t	pr_pid;
+	pid_t	pr_ppid;
+	pid_t	pr_pgrp;
+	pid_t	pr_sid;
+	struct timeval pr_utime;	/* User time */
+	struct timeval pr_stime;	/* System time */
+	struct timeval pr_cutime;	/* Cumulative user time */
+	struct timeval pr_cstime;	/* Cumulative system time */
+#if 0
+	long	pr_instr;		/* Current instruction */
+#endif
+	elf_gregset_t pr_reg;	/* GP registers */
+
 	/* When using FDPIC, the loadmap addresses need to be communicated
 	 * to GDB in order for GDB to do the necessary relocations.  The
 	 * fields (below) used to communicate this information are placed
@@ -69,7 +102,7 @@ struct elf_prstatus
 	 */
 	unsigned long pr_exec_fdpic_loadmap;
 	unsigned long pr_interp_fdpic_loadmap;
-#endif
+
 	int pr_fpvalid;		/* True if math co-processor being used.  */
 };
 
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 11b64a6..9cb496b 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -977,7 +977,11 @@ static void final_note(u32 *buf)
 
 void crash_save_cpu(struct pt_regs *regs, int cpu)
 {
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+	struct elf_fdpic_prstatus prstatus;
+#else
 	struct elf_prstatus prstatus;
+#endif
 	u32 *buf;
 
 	if ((cpu < 0) || (cpu >= nr_cpu_ids))
-- 
2.4.10

[PATCH 06/14] Move ep_take_care_of_epollwakeup() to fs/eventpoll.c

[Palmer Dabbelt]

This doesn't make any sense to expose to userspace, so it's been moved
to the one user.  This was introduced by commit 95f19f658ce1 ("epoll:
drop EPOLLWAKEUP if PM_SLEEP is disabled").

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/eventpoll.c                 | 13 +++++++++++++
 include/uapi/linux/eventpoll.h | 12 ------------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 1e009ca..aadee3d 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1812,6 +1812,19 @@ SYSCALL_DEFINE1(epoll_create, int, size)
 	return sys_epoll_create1(0);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
+		epev->events &= ~EPOLLWAKEUP;
+}
+#else
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	epev->events &= ~EPOLLWAKEUP;
+}
+#endif
+
 /*
  * The following function implements the controller interface for
  * the eventpoll file that enables the insertion/removal/change of
diff --git a/include/uapi/linux/eventpoll.h b/include/uapi/linux/eventpoll.h
index bc81fb2..7850373 100644
--- a/include/uapi/linux/eventpoll.h
+++ b/include/uapi/linux/eventpoll.h
@@ -61,16 +61,4 @@ struct epoll_event {
 	__u64 data;
 } EPOLL_PACKED;
 
-#ifdef CONFIG_PM_SLEEP
-static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
-{
-	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
-		epev->events &= ~EPOLLWAKEUP;
-}
-#else
-static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
-{
-	epev->events &= ~EPOLLWAKEUP;
-}
-#endif
 #endif /* _UAPI_LINUX_EVENTPOLL_H */
-- 
2.4.10

[PATCH 07/14] Make FB_BACKLIGHT_{LEVELS,MAX} always visible

[Palmer Dabbelt]

Nothing else in the kernel defines this, and this header is visible to
userspace.  Rather than hiding it in an #ifdef, I think it's sane to
just make this visible to userspace.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/uapi/linux/fb.h | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/include/uapi/linux/fb.h b/include/uapi/linux/fb.h
index fb795c3..8926f13 100644
--- a/include/uapi/linux/fb.h
+++ b/include/uapi/linux/fb.h
@@ -392,11 +392,8 @@ struct fb_cursor {
 	struct fb_image	image;	/* Cursor image */
 };
 
-#ifdef CONFIG_FB_BACKLIGHT
 /* Settings for the generic backlight code */
 #define FB_BACKLIGHT_LEVELS	128
 #define FB_BACKLIGHT_MAX	0xFF
-#endif
-
 
 #endif /* _UAPI_LINUX_FB_H */
-- 
2.4.10

[PATCH 08/14] Move MAX_SHARED_LIBS to fs/binfmt_flat.c

[Palmer Dabbelt]

I'm not sure what this is, but it doesn't feel like something that
should be exposed to userspace here.  I'm assuming this file was
exposed for the structure in it, which doesn't depend on
MAX_SHARED_LIBS.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 fs/binfmt_flat.c          | 6 ++++++
 include/uapi/linux/flat.h | 6 ------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index f723cd3..e89fb43 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -72,6 +72,12 @@
 #define RELOC_FAILED 0xff00ff01		/* Relocation incorrect somewhere */
 #define UNLOADED_LIB 0x7ff000ff		/* Placeholder for unused library */
 
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+#define	MAX_SHARED_LIBS			(4)
+#else
+#define	MAX_SHARED_LIBS			(1)
+#endif
+
 struct lib_info {
 	struct {
 		unsigned long start_code;		/* Start of text segment */
diff --git a/include/uapi/linux/flat.h b/include/uapi/linux/flat.h
index 88cd6ba..1b177c7 100644
--- a/include/uapi/linux/flat.h
+++ b/include/uapi/linux/flat.h
@@ -13,12 +13,6 @@
 
 #define	FLAT_VERSION			0x00000004L
 
-#ifdef CONFIG_BINFMT_SHARED_FLAT
-#define	MAX_SHARED_LIBS			(4)
-#else
-#define	MAX_SHARED_LIBS			(1)
-#endif
-
 /*
  * To make everything easier to port and manage cross platform
  * development,  all fields are in network byte order.
-- 
2.4.10

[PATCH 09/14] Move bp_type_idx to include/linux/hw_breakpoint.h

[Palmer Dabbelt]

This has a "#ifdef CONFIG_*" that used to be exposed to userspace.

The names in here are so generic that I don't think it's a good idea
to expose them to userspace (or even the rest of the kernel).  There are
multiple in-kernel users, so it's been moved to a kernel header file.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 include/linux/hw_breakpoint.h      | 10 ++++++++++
 include/uapi/linux/hw_breakpoint.h | 10 ----------
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/include/linux/hw_breakpoint.h b/include/linux/hw_breakpoint.h
index 0464c85..dfe0376 100644
--- a/include/linux/hw_breakpoint.h
+++ b/include/linux/hw_breakpoint.h
@@ -6,6 +6,16 @@
 
 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 
+enum bp_type_idx {
+	TYPE_INST	= 0,
+#if defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
+	TYPE_DATA	= 0,
+#else
+	TYPE_DATA	= 1,
+#endif
+	TYPE_MAX
+};
+
 extern int __init init_hw_breakpoint(void);
 
 static inline void hw_breakpoint_init(struct perf_event_attr *attr)
diff --git a/include/uapi/linux/hw_breakpoint.h b/include/uapi/linux/hw_breakpoint.h
index b04000a..7a6a5a7 100644
--- a/include/uapi/linux/hw_breakpoint.h
+++ b/include/uapi/linux/hw_breakpoint.h
@@ -17,14 +17,4 @@ enum {
 	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
 };
 
-enum bp_type_idx {
-	TYPE_INST 	= 0,
-#ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
-	TYPE_DATA	= 0,
-#else
-	TYPE_DATA	= 1,
-#endif
-	TYPE_MAX
-};
-
 #endif /* _UAPI_LINUX_HW_BREAKPOINT_H */
-- 
2.4.10

[PATCH 10/14] Move USE_WCACHING to drivers/block/pktcdvd.c

[Palmer Dabbelt]

I don't think this was ever intended to be exposed to userspace, but
it did require an "#ifdef CONFIG_*".  Since the name is kind of
generic and was only used in one place, I've moved the definition to
the one user.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 drivers/block/pktcdvd.c      | 11 +++++++++++
 include/uapi/linux/pktcdvd.h | 11 -----------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 2f477d4..55f0df3 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -90,6 +90,17 @@ do {									\
 
 #define MAX_SPEED 0xffff
 
+/*
+ * use drive write caching -- we need deferred error handling to be
+ * able to successfully recover with this option (drive will return good
+ * status as soon as the cdb is validated).
+ */
+#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
+#define USE_WCACHING		1
+#else
+#define USE_WCACHING		0
+#endif
+
 static DEFINE_MUTEX(pktcdvd_mutex);
 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
 static struct proc_dir_entry *pkt_proc;
diff --git a/include/uapi/linux/pktcdvd.h b/include/uapi/linux/pktcdvd.h
index 2640b9d..05c2bee 100644
--- a/include/uapi/linux/pktcdvd.h
+++ b/include/uapi/linux/pktcdvd.h
@@ -29,17 +29,6 @@
 #define PACKET_WAIT_TIME	(HZ * 5 / 1000)
 
 /*
- * use drive write caching -- we need deferred error handling to be
- * able to successfully recover with this option (drive will return good
- * status as soon as the cdb is validated).
- */
-#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
-#define USE_WCACHING		1
-#else
-#define USE_WCACHING		0
-#endif
-
-/*
  * No user-servicable parts beyond this point ->
  */
 
-- 
2.4.10

[PATCH 11/14] Always define MAX_RAW_MINORS as 2**20 in userspace

[Palmer Dabbelt]

While I don't think this was ever meant to be exposed to userspace, if
anyone is using it then this will at least provide a correct (if
unlikely) definition.

MAX_RAW_MINORS used to be used in the kernel, where it's been replaced
with CONFIG_MAX_RAW_MINORS.

Note that there's a checkpatch.pl warning about a split config string
here, but I've left that alone.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 drivers/char/raw.c       | 7 ++++---
 include/uapi/linux/raw.h | 2 +-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index 60316fb..2a69117 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -36,7 +36,7 @@ static struct raw_device_data *raw_devices;
 static DEFINE_MUTEX(raw_mutex);
 static const struct file_operations raw_ctl_fops; /* forward declaration */
 
-static int max_raw_minors = MAX_RAW_MINORS;
+static int max_raw_minors = CONFIG_MAX_RAW_DEVS;
 
 module_param(max_raw_minors, int, 0);
 MODULE_PARM_DESC(max_raw_minors, "Maximum number of raw devices (1-65536)");
@@ -317,8 +317,9 @@ static int __init raw_init(void)
 
 	if (max_raw_minors < 1 || max_raw_minors > 65536) {
 		printk(KERN_WARNING "raw: invalid max_raw_minors (must be"
-			" between 1 and 65536), using %d\n", MAX_RAW_MINORS);
-		max_raw_minors = MAX_RAW_MINORS;
+			" between 1 and 65536), using %d\n",
+		       max_raw_minors);
+		max_raw_minors = 65536;
 	}
 
 	raw_devices = vzalloc(sizeof(struct raw_device_data) * max_raw_minors);
diff --git a/include/uapi/linux/raw.h b/include/uapi/linux/raw.h
index 62d543e..f3d009b 100644
--- a/include/uapi/linux/raw.h
+++ b/include/uapi/linux/raw.h
@@ -13,6 +13,6 @@ struct raw_config_request
 	__u64	block_minor;
 };
 
-#define MAX_RAW_MINORS CONFIG_MAX_RAW_DEVS
+#define MAX_RAW_MINORS (1 << 20)
 
 #endif /* __LINUX_RAW_H */
-- 
2.4.10

[PATCH 12/14] Remove AT_VECTOR_SIZE_ARCH on x86

[Palmer Dabbelt]

It looks like there aren't actually users of this macro anywhere:

 * The kernel doesn't use it on x86 because we don't suppor ELF FDPIC.

 * The only Google results point to LMKL patches, both the one that
   wrote this (from 2010) and my patch to hide it behind __KERNEL__.

 * I grep'd through all the source tarballs on my machine, and the
   only packages that matched were the kernel and crui (which copied a
   PPC kernel header).

Since I'm not sure how to actually provide the right answer (if I
understand correctly, CONFIG_IA32_EMULATION is not __i386__), the only
thing I can think of to do is to just remove the definition.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 arch/x86/include/uapi/asm/auxvec.h | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/x86/include/uapi/asm/auxvec.h b/arch/x86/include/uapi/asm/auxvec.h
index 77203ac..1316b4c 100644
--- a/arch/x86/include/uapi/asm/auxvec.h
+++ b/arch/x86/include/uapi/asm/auxvec.h
@@ -9,11 +9,4 @@
 #endif
 #define AT_SYSINFO_EHDR		33
 
-/* entries in ARCH_DLINFO: */
-#if defined(CONFIG_IA32_EMULATION) || !defined(CONFIG_X86_64)
-# define AT_VECTOR_SIZE_ARCH 2
-#else /* else it's non-compat x86-64 */
-# define AT_VECTOR_SIZE_ARCH 1
-#endif
-
 #endif /* _ASM_X86_AUXVEC_H */
-- 
2.4.10

[PATCH 13/14] Hide CONFIG_PHY_RAM_BASE_ADDRESS from userspace

[Palmer Dabbelt]

This feels a bit odd, but I couldn't really come up with a better way to
do it.  There already appears to be a workaround for this macro not
being defined in userspace, so I figured I'd better leave that in place,
since someone is probably using it.

The result is that unless you include <asm/fixed_code.h> before
<uapi/asm/fixed_code.h> then you'll get the wrong offsets.  The only
user of <uapi/asm/fixed_code.h> is currently <asm/fixed_code.h>, so it's
at least safe for now.  There's a CPP error in there to check for this.
---
 arch/blackfin/include/asm/fixed_code.h      |  6 +++++
 arch/blackfin/include/uapi/asm/fixed_code.h | 35 ++++++++++++++++-------------
 2 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/arch/blackfin/include/asm/fixed_code.h b/arch/blackfin/include/asm/fixed_code.h
index bc330f0..7e03b9b 100644
--- a/arch/blackfin/include/asm/fixed_code.h
+++ b/arch/blackfin/include/asm/fixed_code.h
@@ -9,6 +9,12 @@
 #ifndef __BFIN_ASM_FIXED_CODE_H__
 #define __BFIN_ASM_FIXED_CODE_H__
 
+#ifdef CONFIG_PHY_RAM_BASE_ADDRESS
+#define CONFIG_PHY_RAM_BASE_ADDRESS 0x0
+#endif
+
+#define PHY_RAM_BASE_ADDRESS CONFIG_PHY_RAM_BASE_ADDRESS
+
 #include <uapi/asm/fixed_code.h>
 
 #ifndef __ASSEMBLY__
diff --git a/arch/blackfin/include/uapi/asm/fixed_code.h b/arch/blackfin/include/uapi/asm/fixed_code.h
index 3bef1dc..50b70a0 100644
--- a/arch/blackfin/include/uapi/asm/fixed_code.h
+++ b/arch/blackfin/include/uapi/asm/fixed_code.h
@@ -10,29 +10,32 @@
 #ifndef _UAPI__BFIN_ASM_FIXED_CODE_H__
 #define _UAPI__BFIN_ASM_FIXED_CODE_H__
 
-
-#ifndef CONFIG_PHY_RAM_BASE_ADDRESS
-#define CONFIG_PHY_RAM_BASE_ADDRESS	0x0
+#ifndef PHY_RAM_BASE_ADDRESS
+#ifdef __KERNEL__
+#error "Don't include <uapi/asm/fixed_code.h>, include <asm/fixed_code.h>"
+#else
+#define PHY_RAM_BASE_ADDRESS	0x0
+#endif
 #endif
 
-#define FIXED_CODE_START	(CONFIG_PHY_RAM_BASE_ADDRESS + 0x400)
+#define FIXED_CODE_START	(PHY_RAM_BASE_ADDRESS + 0x400)
 
-#define SIGRETURN_STUB		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x400)
+#define SIGRETURN_STUB		(PHY_RAM_BASE_ADDRESS + 0x400)
 
-#define ATOMIC_SEQS_START	(CONFIG_PHY_RAM_BASE_ADDRESS + 0x410)
+#define ATOMIC_SEQS_START	(PHY_RAM_BASE_ADDRESS + 0x410)
 
-#define ATOMIC_XCHG32		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x410)
-#define ATOMIC_CAS32		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x420)
-#define ATOMIC_ADD32		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x430)
-#define ATOMIC_SUB32		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x440)
-#define ATOMIC_IOR32		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x450)
-#define ATOMIC_AND32		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x460)
-#define ATOMIC_XOR32		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x470)
+#define ATOMIC_XCHG32		(PHY_RAM_BASE_ADDRESS + 0x410)
+#define ATOMIC_CAS32		(PHY_RAM_BASE_ADDRESS + 0x420)
+#define ATOMIC_ADD32		(PHY_RAM_BASE_ADDRESS + 0x430)
+#define ATOMIC_SUB32		(PHY_RAM_BASE_ADDRESS + 0x440)
+#define ATOMIC_IOR32		(PHY_RAM_BASE_ADDRESS + 0x450)
+#define ATOMIC_AND32		(PHY_RAM_BASE_ADDRESS + 0x460)
+#define ATOMIC_XOR32		(PHY_RAM_BASE_ADDRESS + 0x470)
 
-#define ATOMIC_SEQS_END		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x480)
+#define ATOMIC_SEQS_END		(PHY_RAM_BASE_ADDRESS + 0x480)
 
-#define SAFE_USER_INSTRUCTION   (CONFIG_PHY_RAM_BASE_ADDRESS + 0x480)
+#define SAFE_USER_INSTRUCTION   (PHY_RAM_BASE_ADDRESS + 0x480)
 
-#define FIXED_CODE_END		(CONFIG_PHY_RAM_BASE_ADDRESS + 0x490)
+#define FIXED_CODE_END		(PHY_RAM_BASE_ADDRESS + 0x490)
 
 #endif /* _UAPI__BFIN_ASM_FIXED_CODE_H__ */
-- 
2.4.10

[PATCH 14/14] Re-enable and clean up "check_config()" in headers_check.pl

[Palmer Dabbelt]

I recently got bit by a CONFIG_ in userspace bug.  This has apparently
happened before, but the check got disabled for triggering too much.
In order to reduce false positives, I added some hueristics to avoid
detecting comments.

Since these tests all pass, I've now re-enabled them.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
---
 scripts/headers_check.pl | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/scripts/headers_check.pl b/scripts/headers_check.pl
index 62320f9..1634b51 100755
--- a/scripts/headers_check.pl
+++ b/scripts/headers_check.pl
@@ -27,6 +27,7 @@ my $ret = 0;
 my $line;
 my $lineno = 0;
 my $filename;
+my $check_config_in_multiline_comment = 0;
 
 foreach my $file (@files) {
 	$filename = $file;
@@ -40,7 +41,7 @@ foreach my $file (@files) {
 		&check_asm_types();
 		&check_sizetypes();
 		&check_declarations();
-		# Dropped for now. Too much noise &check_config();
+		&check_config();
 	}
 	close $fh;
 }
@@ -78,7 +79,21 @@ sub check_declarations
 
 sub check_config
 {
-	if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
+	my $nocomments = $line;
+	$nocomments =~ s/\/\*.*\*\///; # Remove ANSI-style comments (/* to */)
+	$nocomments =~ s/\/\/.*//;     # Remove C99-style comments (// to EOL)
+
+	# Check to see if we're within a multiline comment, and if so
+	# just remove the whole line.  I tried matching on '^ * ', but
+	# there's one header that doesn't prepend multi-line comments
+	# with * so that won't work.
+	if ($nocomments =~ m/\/\*/) { $check_config_in_multiline_comment = 1; }
+	if ($nocomments =~ m/\*\//) { $check_config_in_multiline_comment = 0; }
+	if ($check_config_in_multiline_comment == 1) { $nocomments = "" }
+
+	# Check to see if there is something that looks like CONFIG_
+	# inside a userspace-accessible header file and if so, print that out.
+	if ($nocomments =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
 		printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n";
 	}
 }
-- 
2.4.10

Re: [PATCH 06/14] Move ep_take_care_of_epollwakeup() to fs/eventpoll.c

[Thomas Huth]

On 10/11/2015 02.31, Palmer Dabbelt wrote:
> This doesn't make any sense to expose to userspace, so it's been moved
> to the one user.  This was introduced by commit 95f19f658ce1 ("epoll:
> drop EPOLLWAKEUP if PM_SLEEP is disabled").
> 
> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
> ---
>   fs/eventpoll.c                 | 13 +++++++++++++
>   include/uapi/linux/eventpoll.h | 12 ------------
>   2 files changed, 13 insertions(+), 12 deletions(-)
> 
> diff --git a/fs/eventpoll.c b/fs/eventpoll.c
> index 1e009ca..aadee3d 100644
> --- a/fs/eventpoll.c
> +++ b/fs/eventpoll.c
> @@ -1812,6 +1812,19 @@ SYSCALL_DEFINE1(epoll_create, int, size)
>   	return sys_epoll_create1(0);
>   }
>   
> +#ifdef CONFIG_PM_SLEEP
> +static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
> +{
> +	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
> +		epev->events &= ~EPOLLWAKEUP;
> +}
> +#else
> +static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
> +{
> +	epev->events &= ~EPOLLWAKEUP;
> +}
> +#endif
> +
>   /*
>    * The following function implements the controller interface for
>    * the eventpoll file that enables the insertion/removal/change of
> diff --git a/include/uapi/linux/eventpoll.h b/include/uapi/linux/eventpoll.h
> index bc81fb2..7850373 100644
> --- a/include/uapi/linux/eventpoll.h
> +++ b/include/uapi/linux/eventpoll.h
> @@ -61,16 +61,4 @@ struct epoll_event {
>   	__u64 data;
>   } EPOLL_PACKED;
>   
> -#ifdef CONFIG_PM_SLEEP
> -static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
> -{
> -	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
> -		epev->events &= ~EPOLLWAKEUP;
> -}
> -#else
> -static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
> -{
> -	epev->events &= ~EPOLLWAKEUP;
> -}
> -#endif
>   #endif /* _UAPI_LINUX_EVENTPOLL_H */

  Hi!

Looks like this patch has never been merged? ... I just came across this 
"#ifdef CONFIG_..." in the uapi directory, and it also seems wrong to me to 
check CONFIG_* switches here, so could somebody maybe pick this patch up now 
and merge it?

  Thanks,
   Thomas

Re: [PATCH 03/14] Move COMPAT_ATM_ADDPARTY to net/atm/svc.c

[Thomas Huth]

On 10/11/2015 02.31, Palmer Dabbelt wrote:
> This used to be behind an #ifdef COMPAT_COMPAT, so most of userspace
> wouldn't have seen the definition before.  Unfortunately this header
> file became visible to userspace, so the definition has instead been
> moved to net/atm/svc.c (the only user).
> 
> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>
> ---
>   include/uapi/linux/atmdev.h | 4 ----
>   net/atm/svc.c               | 5 +++++
>   2 files changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/include/uapi/linux/atmdev.h b/include/uapi/linux/atmdev.h
> index 93e0ec0..3dcec70 100644
> --- a/include/uapi/linux/atmdev.h
> +++ b/include/uapi/linux/atmdev.h
> @@ -100,10 +100,6 @@ struct atm_dev_stats {
>   					/* use backend to make new if */
>   #define ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct atm_iobuf)
>    					/* add party to p2mp call */
> -#ifdef CONFIG_COMPAT
> -/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
> -#define COMPAT_ATM_ADDPARTY  	_IOW('a', ATMIOC_SPECIAL+4,struct compat_atm_iobuf)
> -#endif
>   #define ATM_DROPPARTY 	_IOW('a', ATMIOC_SPECIAL+5,int)
>   					/* drop party from p2mp call */
>   
> diff --git a/net/atm/svc.c b/net/atm/svc.c
> index 3fa0a9e..9e2e6ef 100644
> --- a/net/atm/svc.c
> +++ b/net/atm/svc.c
> @@ -27,6 +27,11 @@
>   #include "signaling.h"
>   #include "addr.h"
>   
> +#ifdef CONFIG_COMPAT
> +/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
> +#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4, struct compat_atm_iobuf)
> +#endif
> +
>   static int svc_create(struct net *net, struct socket *sock, int protocol,
>   		      int kern);
>   

  Hi!

The CONFIG_* switch is still there in the atmdev.h uapi header ... could 
somebody please pick this patch up to fix it?

  Thanks,
   Thomas

Re: [PATCH 03/14] Move COMPAT_ATM_ADDPARTY to net/atm/svc.c

[Arnd Bergmann]

On Fri, Feb 10, 2023, at 15:55, Thomas Huth wrote:
> On 10/11/2015 02.31, Palmer Dabbelt wrote:
>> This used to be behind an #ifdef COMPAT_COMPAT, so most of userspace
>> wouldn't have seen the definition before.  Unfortunately this header
>> file became visible to userspace, so the definition has instead been
>> moved to net/atm/svc.c (the only user).
>> 
>> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
>> Reviewed-by: Andrew Waterman <waterman@eecs.berkeley.edu>
>> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu>

Reviewed-by: Arnd Bergmann <arnd@arndb.de>

It took me a bit to figure out why there is a separate command
code but no special handler for the compat structure, aside from
being in the wrong file it does look correct.

>> +#ifdef CONFIG_COMPAT
>> +/* It actually takes struct sockaddr_atmsvc, not struct atm_iobuf */
>> +#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4, struct compat_atm_iobuf)
>> +#endif

We could actually drop the #ifdef here as well, or moving into
the existing #ifdef.

>> +
>>   static int svc_create(struct net *net, struct socket *sock, int protocol,
>>   		      int kern);
>
> The CONFIG_* switch is still there in the atmdev.h uapi header ... could 
> somebody please pick this patch up to fix it?

It should get merged through the netdev tree, as Chas does not have
a separate git tree for drivers/atm.

I don't know what happened to the rest of the series, but if there are
additional patches that got lost, merging them all through either the
asm-generic or the mm tree would work as well.

Any chance you or Palmer could rebase the series to 6.2-rc and
see what remains?

    Arnd