Recently to prevent issues with SECCOMP_RET_KILL and similar signals
being changed before they are delivered SA_IMMUTABLE was added.
Unfortunately this broke debuggers[1][2] which reasonably expect
to be able to trap synchronous SIGTRAP and SIGSEGV even when
the target process is not configured to handle those signals.
Add force_exit_sig and use it instead of force_fatal_sig where
historically the code has directly called do_exit. This has the
implementation benefits of going through the signal exit path
(including generating core dumps) without the danger of allowing
userspace to ignore or change these signals.
This avoids userspace regressions as older kernels exited with do_exit
which debuggers also can not intercept.
In the future is should be possible to improve the quality of
implementation of the kernel by changing some of these force_exit_sig
calls to force_fatal_sig. That can be done where it matters on
a case-by-case basis with careful analysis.
Reported-by: Kyle Huey <me@kylehuey.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
[1] https://lkml.kernel.org/r/CAP045AoMY4xf8aC_4QU_-j7obuEPYgTcnQQP3Yxk=2X90jtpjw@mail.gmail.com
[2] https://lkml.kernel.org/r/20211117150258.GB5403@xsang-OptiPlex-9020
Fixes: 00b06da29c ("signal: Add SA_IMMUTABLE to ensure forced siganls do not get changed")
Fixes: a3616a3c02 ("signal/m68k: Use force_sigsegv(SIGSEGV) in fpsp040_die")
Fixes: 83a1f27ad7 ("signal/powerpc: On swapcontext failure force SIGSEGV")
Fixes: 9bc508cf07 ("signal/s390: Use force_sigsegv in default_trap_handler")
Fixes: 086ec444f8 ("signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig")
Fixes: c317d306d5 ("signal/sparc32: Exit with a fatal signal when try_to_clear_window_buffer fails")
Fixes: 695dd0d634 ("signal/x86: In emulate_vsyscall force a signal instead of calling do_exit")
Fixes: 1fbd60df8a ("signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved.")
Fixes: 941edc5bf1 ("exit/syscall_user_dispatch: Send ordinary signals on failure")
Link: https://lkml.kernel.org/r/871r3dqfv8.fsf_-_@email.froward.int.ebiederm.org
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Kyle Huey <khuey@kylehuey.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
kernel test robot <oliver.sang@intel.com> writes[1]:
>
> Greeting,
>
> FYI, we noticed the following commit (built with gcc-9):
>
> commit: 1a4d21a23c ("signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
>
> in testcase: trinity
> version: trinity-static-i386-x86_64-1c734c75-1_2020-01-06
> with following parameters:
>
>
> [ 70.645554][ T3747] kernel BUG at arch/x86/kernel/vm86_32.c:109!
> [ 70.646185][ T3747] invalid opcode: 0000 [#1] SMP
> [ 70.646682][ T3747] CPU: 0 PID: 3747 Comm: trinity-c6 Not tainted 5.15.0-rc1-00009-g1a4d21a23c4c #1
> [ 70.647598][ T3747] EIP: save_v86_state (arch/x86/kernel/vm86_32.c:109 (discriminator 3))
> [ 70.648113][ T3747] Code: 89 c3 64 8b 35 60 b8 25 c2 83 ec 08 89 55 f0 8b 96 10 19 00 00 89 55 ec e8 c6 2d 0c 00 fb 8b 55 ec 85 d2 74 05 83 3a 00 75 02 <0f> 0b 8b 86 10 19 00 00 8b 4b 38 8b 78 48 31 cf 89 f8 8b 7a 4c 81
> [ 70.650136][ T3747] EAX: 00000001 EBX: f5f49fac ECX: 0000000b EDX: f610b600
> [ 70.650852][ T3747] ESI: f5f79cc0 EDI: f5f79cc0 EBP: f5f49f04 ESP: f5f49ef0
> [ 70.651593][ T3747] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010246
> [ 70.652413][ T3747] CR0: 80050033 CR2: 00004000 CR3: 35fc7000 CR4: 000406d0
> [ 70.653169][ T3747] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
> [ 70.653897][ T3747] DR6: fffe0ff0 DR7: 00000400
> [ 70.654382][ T3747] Call Trace:
> [ 70.654719][ T3747] arch_do_signal_or_restart (arch/x86/kernel/signal.c:792 arch/x86/kernel/signal.c:867)
> [ 70.655288][ T3747] exit_to_user_mode_prepare (kernel/entry/common.c:174 kernel/entry/common.c:209)
> [ 70.655854][ T3747] irqentry_exit_to_user_mode (kernel/entry/common.c:126 kernel/entry/common.c:317)
> [ 70.656450][ T3747] irqentry_exit (kernel/entry/common.c:406)
> [ 70.656897][ T3747] exc_page_fault (arch/x86/mm/fault.c:1535)
> [ 70.657369][ T3747] ? sysvec_kvm_asyncpf_interrupt (arch/x86/mm/fault.c:1488)
> [ 70.657989][ T3747] handle_exception (arch/x86/entry/entry_32.S:1085)
vm86_32.c:109 is: "BUG_ON(!vm86 || !vm86->user_vm86)"
When trying to understand the failure Brian Gerst pointed out[2] that
the code does not need protection against vm86->user_vm86 being NULL.
The copy_from_user code will already handles that case if the address
is going to fault.
Looking futher I realized that if we care about not allowing struct
vm86plus_struct at address 0 it should be do_sys_vm86 (the system
call) that does the filtering. Not way down deep when the emulation
has completed in save_v86_state.
So let's just remove the silly case of attempting to filter a
userspace address with a BUG_ON. Existing userspace can't break and
it won't make the kernel any more attackable as the userspace access
helpers will handle it, if it isn't a good userspace pointer.
I have run the reproducer the fuzzer gave me before I made this change
and it reproduced, and after I made this change and I have not seen
the reported failure. So it does looks like this fixes the reported
issue.
[1] https://lkml.kernel.org/r/20211112074030.GB19820@xsang-OptiPlex-9020
[2] https://lkml.kernel.org/r/CAMzpN2jkK5sAv-Kg_kVnCEyVySiqeTdUORcC=AdG1gV6r8nUew@mail.gmail.com
Suggested-by: Brian Gerst <brgerst@gmail.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Tested-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Now that force_fatal_sig exists it is unnecessary and a bit confusing
to use force_sigsegv in cases where the simpler force_fatal_sig is
wanted. So change every instance we can to make the code clearer.
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Link: https://lkml.kernel.org/r/877de7jrev.fsf@disp2133
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Update save_v86_state to always complete all of it's work except
possibly some of the copies to userspace even if save_v86_state takes
a fault. This ensures that the kernel is always in a sane state, even
if userspace has done something silly.
When save_v86_state takes a fault update it to force userspace to take
a SIGSEGV and terminate the userspace application.
As Andy pointed out in review of the first version of this change
there are races between sigaction and the application terinating. Now
that the code has been modified to always perform all save_v86_state's
work (except possibly copying to userspace) those races do not matter
from a kernel perspective.
Forcing the userspace application to terminate (by resetting it's
handler to SIGDFL) is there to keep everything as close to the current
behavior as possible while removing the unique (and difficult to
maintain) use of do_exit.
If this new SIGSEGV happens during handle_signal the next time around
the exit_to_user_mode_loop, SIGSEGV will be delivered to userspace.
All of the callers of handle_vm86_trap and handle_vm86_fault run the
exit_to_user_mode_loop before they return to userspace any signal sent
to the current task during their execution will be delivered to the
current task before that tasks exits to usermode.
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: H Peter Anvin <hpa@zytor.com>
v1: https://lkml.kernel.org/r/20211020174406.17889-10-ebiederm@xmission.com
Link: https://lkml.kernel.org/r/877de1xcr6.fsf_-_@disp2133
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
The implementation was rather buggy. It unconditionally marked PTEs
read-only, even for VM_SHARED mappings. I'm not sure whether this is
actually a problem, but it certainly seems unwise. More importantly, it
released the mmap lock before flushing the TLB, which could allow a racing
CoW operation to falsely believe that the underlying memory was not
writable.
I can't find any users at all of this mechanism, so just remove it.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Stas Sergeev <stsp2@yandex.ru>
Link: https://lkml.kernel.org/r/f3086de0babcab36f69949b5780bde851f719bc8.1611078018.git.luto@kernel.org
Just do a copyin of what we want into a local variable and
be done with that. We are guaranteed to be on shallow stack
here...
Note that conditional expression for range passed to access_ok()
in mainline had been pointless all along - the only difference
between vm86plus_struct and vm86_struct is that the former has
one extra field in the end and when we get to copyin of that
field (conditional upon 'plus' argument), we use copy_from_user().
Moreover, all fields starting with ->int_revectored are copied
that way, so we only need that check (be it done by access_ok()
or by user_access_begin()) only on the beginning of the structure -
the fields that used to be covered by that get_user_try() block.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
force_iret() was originally intended to prevent the return to user mode with
the SYSRET or SYSEXIT instructions, in cases where the register state could
have been changed to be incompatible with those instructions. The entry code
has been significantly reworked since then, and register state is validated
before SYSRET or SYSEXIT are used. force_iret() no longer serves its original
purpose and can be eliminated.
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/20191219115812.102620-1-brgerst@gmail.com
All of the remaining callers pass current into force_sig so
remove the task parameter to make this obvious and to make
misuse more difficult in the future.
This also makes it clear force_sig passes current into force_sig_info.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
GCC complains about unused variable 'vma' in mark_screen_rdonly() if THP is
disabled:
arch/x86/kernel/vm86_32.c: In function ‘mark_screen_rdonly’:
arch/x86/kernel/vm86_32.c:180:26: warning: unused variable ‘vma’
[-Wunused-variable]
struct vm_area_struct *vma = find_vma(mm, 0xA0000);
That's silly. pmd_trans_huge() resolves to 0 when THP is disabled, so the
whole block should be eliminated.
Moving the variable declaration outside the if() block shuts GCC up.
Reported-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Carlos O'Donell <carlos@redhat.com>
Link: http://lkml.kernel.org/r/20170213125228.63645-1-kirill.shutemov@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
So the old one didn't work properly before alternatives had run.
And it was supposed to provide an optimized JMP because the
assumption was that the offset it is jumping to is within a
signed byte and thus a two-byte JMP.
So I did an x86_64 allyesconfig build and dumped all possible
sites where static_cpu_has() was used. The optimization amounted
to all in all 12(!) places where static_cpu_has() had generated
a 2-byte JMP. Which has saved us a whopping 36 bytes!
This clearly is not worth the trouble so we can remove it. The
only place where the optimization might count - in __switch_to()
- we will handle differently. But that's not subject of this
patch.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453842730-28463-6-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Change to use the normal pt_regs area to enter and exit vm86
mode. This is done by increasing the padding at the top of the
stack to make room for the extra vm86 segment slots in the IRET
frame. It then saves the 32-bit regs in the off-stack vm86
data, and copies in the vm86 regs. Exiting back to 32-bit mode
does the reverse. This allows removing the hacks to jump
directly into the exit asm code due to having to change the
stack pointer. Returning normally from the vm86 syscall and the
exception handlers allows things like ptrace and auditing to work properly.
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1438148483-11932-5-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 49cb25e929 x86: 'get rid of pt_regs argument in vm86/vm86old'
got rid of the pt_regs stub for sys_vm86old and sys_vm86. The functions
were, however, not changed to use the calling convention for syscalls.
[AV: killed asmlinkage_protect() - it's done automatically now]
Reported-and-tested-by: Hans de Bruin <jmdebruin@xmsnet.nl>
Cc: stable@vger.kernel.org
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
TIF_NOTIFY_RESUME will work in precisely the same way; all that
is achieved by TIF_IRET is appearing that there's some work to be
done, so we end up on the iret exit path. Just use NOTIFY_RESUME.
And for execve() do that in 32bit start_thread(), not sys_execve()
itself.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Use a more current logging style:
- Bare printks should have a KERN_<LEVEL> for consistency's sake
- Add pr_fmt where appropriate
- Neaten some macro definitions
- Convert some Ok output to OK
- Use "%s: ", __func__ in pr_fmt for summit
- Convert some printks to pr_<level>
Message output is not identical in all cases.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: levinsasha928@gmail.com
Link: http://lkml.kernel.org/r/1337655007.24226.10.camel@joe2Laptop
[ merged two similar patches, tidied up the changelog ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 cleanups from Peter Anvin:
"The biggest textual change is the cleanup to use symbolic constants
for x86 trap values.
The only *functional* change and the reason for the x86/x32 dependency
is the move of is_ia32_task() into <asm/thread_info.h> so that it can
be used in other code that needs to understand if a system call comes
from the compat entry point (and therefore uses i386 system call
numbers) or not. One intended user for that is the BPF system call
filter. Moving it out of <asm/compat.h> means we can define it
unconditionally, returning always true on i386."
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Move is_ia32_task to asm/thread_info.h from asm/compat.h
x86: Rename trap_no to trap_nr in thread_struct
x86: Use enum instead of literals for trap values
