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341 commits

Author SHA1 Message Date
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
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>
2017-11-02 11:10:55 +01:00
Ingo Molnar
e4a81bfcaa x86/fpu: Rename fpu::fpstate_active to fpu::initialized
The x86 FPU code used to have a complex state machine where both the FPU
registers and the FPU state context could be 'active' (or inactive)
independently of each other - which enabled features like lazy FPU restore.

Much of this complexity is gone in the current code: now we basically can
have FPU-less tasks (kernel threads) that don't use (and save/restore) FPU
state at all, plus full FPU users that save/restore directly with no laziness
whatsoever.

But the fpu::fpstate_active still carries bits of the old complexity - meanwhile
this flag has become a simple flag that shows whether the FPU context saving
area in the thread struct is initialized and used, or not.

Rename it to fpu::initialized to express this simplicity in the name as well.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-30-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:36 +02:00
Linus Torvalds
581bfce969 Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more set_fs removal from Al Viro:
 "Christoph's 'use kernel_read and friends rather than open-coding
  set_fs()' series"

* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: unexport vfs_readv and vfs_writev
  fs: unexport vfs_read and vfs_write
  fs: unexport __vfs_read/__vfs_write
  lustre: switch to kernel_write
  gadget/f_mass_storage: stop messing with the address limit
  mconsole: switch to kernel_read
  btrfs: switch write_buf to kernel_write
  net/9p: switch p9_fd_read to kernel_write
  mm/nommu: switch do_mmap_private to kernel_read
  serial2002: switch serial2002_tty_write to kernel_{read/write}
  fs: make the buf argument to __kernel_write a void pointer
  fs: fix kernel_write prototype
  fs: fix kernel_read prototype
  fs: move kernel_read to fs/read_write.c
  fs: move kernel_write to fs/read_write.c
  autofs4: switch autofs4_write to __kernel_write
  ashmem: switch to ->read_iter
2017-09-14 18:13:32 -07:00
Christoph Hellwig
bdd1d2d3d2 fs: fix kernel_read prototype
Use proper ssize_t and size_t types for the return value and count
argument, move the offset last and make it an in/out argument like
all other read/write helpers, and make the buf argument a void pointer
to get rid of lots of casts in the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-04 19:05:15 -04:00
Andy Lutomirski
99504819fc x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads
Now that pt_regs properly defines segment fields as 16-bit on 32-bit
CPUs, there's no need to mask off the high word.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-30 12:04:41 +02:00
Ingo Molnar
68db0cf106 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>
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>
2017-03-02 08:42:36 +01:00
Linus Torvalds
7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
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>
2016-12-24 11:46:01 -08:00
Dmitry Safonov
6846351052 x86/signal: Add SA_{X32,IA32}_ABI sa_flags
Introduce new flags that defines which ABI to use on creating sigframe.
Those flags kernel will set according to sigaction syscall ABI,
which set handler for the signal being delivered.

So that will drop the dependency on TIF_IA32/TIF_X32 flags on signal deliver.
Those flags will be used only under CONFIG_COMPAT.

Similar way ARM uses sa_flags to differ in which mode deliver signal
for 26-bit applications (look at SA_THIRYTWO).

Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: 0x7f454c46@gmail.com
Cc: oleg@redhat.com
Cc: linux-mm@kvack.org
Cc: gorcunov@openvz.org
Cc: xemul@virtuozzo.com
Link: http://lkml.kernel.org/r/20160905133308.28234-7-dsafonov@virtuozzo.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14 21:28:11 +02:00
Linus Torvalds
5d22fc25d4 mm: remove more IS_ERR_VALUE abuses
The do_brk() and vm_brk() return value was "unsigned long" and returned
the starting address on success, and an error value on failure.  The
reasons are entirely historical, and go back to it basically behaving
like the mmap() interface does.

However, nobody actually wanted that interface, and it causes totally
pointless IS_ERR_VALUE() confusion.

What every single caller actually wants is just the simpler integer
return of zero for success and negative error number on failure.

So just convert to that much clearer and more common calling convention,
and get rid of all the IS_ERR_VALUE() uses wrt vm_brk().

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-27 15:57:31 -07:00
Michal Hocko
864778b154 mm, aout: handle vm_brk failures
vm_brk is allowed to fail but load_aout_binary simply ignores the error
and happily continues.  I haven't noticed any problem from that in real
life but later patches will make the failure more likely because vm_brk
will become killable (resp.  mmap_sem for write waiting will become
killable) so we should be more careful now.

The error handling should be quite straightforward because there are
calls to vm_mmap which check the error properly already.  The only
notable exception is set_brk which is called after beyond_if label.  But
nothing indicates that we cannot move it above set_binfmt as the two do
not depend on each other and fail before we do set_binfmt and alter
reference counting.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23 17:04:14 -07:00
Borislav Petkov
d366bf7eb9 x86/cpufeature: Replace cpu_has_xsave with boot_cpu_has() usage
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>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1459801503-15600-10-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13 11:37:41 +02:00
Linus Torvalds
4302d506d5 Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 sigcontext header cleanups from Ingo Molnar:
 "This series reorganizes and cleans up various aspects of the main
  sigcontext UAPI headers, such as unifying the data structures and
  updating/adding lots of comments to explain all the ABI details and
  quirks.  The headers can now also be built in user-space standalone"

* 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/headers: Clean up too long lines
  x86/headers: Remove <asm/sigcontext.h> references on the kernel side
  x86/headers: Remove direct sigcontext32.h uses
  x86/headers: Convert sigcontext_ia32 uses to sigcontext_32
  x86/headers: Unify 'struct sigcontext_ia32' and 'struct sigcontext_32'
  x86/headers: Make sigcontext pointers bit independent
  x86/headers: Move the 'struct sigcontext' definitions into the UAPI header
  x86/headers: Clean up the kernel's struct sigcontext types to be ABI-clean
  x86/headers: Convert uses of _fpstate_ia32 to _fpstate_32
  x86/headers: Unify 'struct _fpstate_ia32' and i386 struct _fpstate
  x86/headers: Unify register type definitions between 32-bit compat and i386
  x86/headers: Use ABI types consistently in sigcontext*.h
  x86/headers: Separate out legacy user-space structure definitions
  x86/headers: Clean up and better document uapi/asm/sigcontext.h
  x86/headers: Clean up uapi/asm/sigcontext32.h
  x86/headers: Fix (old) header file dependency bug in uapi/asm/sigcontext32.h
2015-11-03 21:05:40 -08:00
Andy Lutomirski
0a6d1fa0d2 x86/vdso: Remove runtime 32-bit vDSO selection
32-bit userspace will now always see the same vDSO, which is
exactly what used to be the int80 vDSO.  Subsequent patches will
clean it up and make it support SYSENTER and SYSCALL using
alternatives.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/e7e6b3526fa442502e6125fe69486aab50813c32.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-07 11:34:08 +02:00
Ingo Molnar
decb4c4115 x86/headers: Remove <asm/sigcontext.h> references on the kernel side
Now that all type definitions are in the UAPI header, include it
directly, instead of through <asm/sigcontext.h>.

[ We still keep asm/sigcontext.h, so that uapi/asm/sigcontext32.h
  can include <asm/sigcontext.h>. ]

Acked-by: Mikko Rapeli <mikko.rapeli@iki.fi>
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: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1441438363-9999-16-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-08 10:06:05 +02:00
Ingo Molnar
711531f4f3 x86/headers: Remove direct sigcontext32.h uses
Now that all sigcontext types are defined in asm/sigcontext.h,
remove the various sigcontext32.h uses in the kernel.

We still keep the header itself, which includes sigcontext.h, in
case user-space relies on it.

Acked-by: Mikko Rapeli <mikko.rapeli@iki.fi>
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: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1441438363-9999-15-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-08 10:03:59 +02:00
Ingo Molnar
8fcb346b91 x86/headers: Convert sigcontext_ia32 uses to sigcontext_32
Use the new name in kernel code, and move the old name to the
user-space-only legacy section of the UAPI header.

Acked-by: Mikko Rapeli <mikko.rapeli@iki.fi>
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: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1441438363-9999-14-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-08 10:03:59 +02:00
Ingo Molnar
86e9fc3a0e x86/headers: Convert uses of _fpstate_ia32 to _fpstate_32
Remove uses of _fpstate_ia32 from the kernel, and move the
legacy _fpstate_ia32 definition to the user-space only portion
of the header.

Acked-by: Mikko Rapeli <mikko.rapeli@iki.fi>
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: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1441438363-9999-9-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-08 10:03:57 +02:00
Brian Gerst
c0bfd26e13 x86/compat: Move copy_siginfo_*_user32() to signal_compat.c
copy_siginfo_to_user32() and copy_siginfo_from_user32() are used
by both the 32-bit compat and x32 ABIs.  Move them to
signal_compat.c.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
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/1434974121-32575-2-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06 15:28:55 +02:00
Linus Torvalds
d70b3ef54c Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core updates from Ingo Molnar:
 "There were so many changes in the x86/asm, x86/apic and x86/mm topics
  in this cycle that the topical separation of -tip broke down somewhat -
  so the result is a more traditional architecture pull request,
  collected into the 'x86/core' topic.

  The topics were still maintained separately as far as possible, so
  bisectability and conceptual separation should still be pretty good -
  but there were a handful of merge points to avoid excessive
  dependencies (and conflicts) that would have been poorly tested in the
  end.

  The next cycle will hopefully be much more quiet (or at least will
  have fewer dependencies).

  The main changes in this cycle were:

   * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas
     Gleixner)

     - This is the second and most intrusive part of changes to the x86
       interrupt handling - full conversion to hierarchical interrupt
       domains:

          [IOAPIC domain]   -----
                                 |
          [MSI domain]      --------[Remapping domain] ----- [ Vector domain ]
                                 |   (optional)          |
          [HPET MSI domain] -----                        |
                                                         |
          [DMAR domain]     -----------------------------
                                                         |
          [Legacy domain]   -----------------------------

       This now reflects the actual hardware and allowed us to distangle
       the domain specific code from the underlying parent domain, which
       can be optional in the case of interrupt remapping.  It's a clear
       separation of functionality and removes quite some duct tape
       constructs which plugged the remap code between ioapic/msi/hpet
       and the vector management.

     - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt
       injection into guests (Feng Wu)

   * x86/asm changes:

     - Tons of cleanups and small speedups, micro-optimizations.  This
       is in preparation to move a good chunk of the low level entry
       code from assembly to C code (Denys Vlasenko, Andy Lutomirski,
       Brian Gerst)

     - Moved all system entry related code to a new home under
       arch/x86/entry/ (Ingo Molnar)

     - Removal of the fragile and ugly CFI dwarf debuginfo annotations.
       Conversion to C will reintroduce many of them - but meanwhile
       they are only getting in the way, and the upstream kernel does
       not rely on them (Ingo Molnar)

     - NOP handling refinements. (Borislav Petkov)

   * x86/mm changes:

     - Big PAT and MTRR rework: making the code more robust and
       preparing to phase out exposing direct MTRR interfaces to drivers -
       in favor of using PAT driven interfaces (Toshi Kani, Luis R
       Rodriguez, Borislav Petkov)

     - New ioremap_wt()/set_memory_wt() interfaces to support
       Write-Through cached memory mappings.  This is especially
       important for good performance on NVDIMM hardware (Toshi Kani)

   * x86/ras changes:

     - Add support for deferred errors on AMD (Aravind Gopalakrishnan)

       This is an important RAS feature which adds hardware support for
       poisoned data.  That means roughly that the hardware marks data
       which it has detected as corrupted but wasn't able to correct, as
       poisoned data and raises an APIC interrupt to signal that in the
       form of a deferred error.  It is the OS's responsibility then to
       take proper recovery action and thus prolonge system lifetime as
       far as possible.

     - Add support for Intel "Local MCE"s: upcoming CPUs will support
       CPU-local MCE interrupts, as opposed to the traditional system-
       wide broadcasted MCE interrupts (Ashok Raj)

     - Misc cleanups (Borislav Petkov)

   * x86/platform changes:

     - Intel Atom SoC updates

  ... and lots of other cleanups, fixlets and other changes - see the
  shortlog and the Git log for details"

* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits)
  x86/hpet: Use proper hpet device number for MSI allocation
  x86/hpet: Check for irq==0 when allocating hpet MSI interrupts
  x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
  x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
  x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail
  genirq: Prevent crash in irq_move_irq()
  genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
  iommu, x86: Properly handle posted interrupts for IOMMU hotplug
  iommu, x86: Provide irq_remapping_cap() interface
  iommu, x86: Setup Posted-Interrupts capability for Intel iommu
  iommu, x86: Add cap_pi_support() to detect VT-d PI capability
  iommu, x86: Avoid migrating VT-d posted interrupts
  iommu, x86: Save the mode (posted or remapped) of an IRTE
  iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
  iommu: dmar: Provide helper to copy shared irte fields
  iommu: dmar: Extend struct irte for VT-d Posted-Interrupts
  iommu: Add new member capability to struct irq_remap_ops
  x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code
  x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
  x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
  ...
2015-06-22 17:59:09 -07:00
Ingo Molnar
19a433f451 x86/asm/entry: Move the compat syscall entry code to arch/x86/entry/
Move the ia32entry.S file over into arch/x86/entry/.

Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-03 18:51:32 +02:00
Ingo Molnar
131484c8da x86/debug: Remove perpetually broken, unmaintainable dwarf annotations
So the dwarf2 annotations in low level assembly code have
become an increasing hindrance: unreadable, messy macros
mixed into some of the most security sensitive code paths
of the Linux kernel.

These debug info annotations don't even buy the upstream
kernel anything: dwarf driven stack unwinding has caused
problems in the past so it's out of tree, and the upstream
kernel only uses the much more robust framepointers based
stack unwinding method.

In addition to that there's a steady, slow bitrot going
on with these annotations, requiring frequent fixups.
There's no tooling and no functionality upstream that
keeps it correct.

So burn down the sick forest, allowing new, healthier growth:

   27 files changed, 350 insertions(+), 1101 deletions(-)

Someone who has the willingness and time to do this
properly can attempt to reintroduce dwarf debuginfo in x86
assembly code plus dwarf unwinding from first principles,
with the following conditions:

 - it should be maximally readable, and maximally low-key to
   'ordinary' code reading and maintenance.

 - find a build time method to insert dwarf annotations
   automatically in the most common cases, for pop/push
   instructions that manipulate the stack pointer. This could
   be done for example via a preprocessing step that just
   looks for common patterns - plus special annotations for
   the few cases where we want to depart from the default.
   We have hundreds of CFI annotations, so automating most of
   that makes sense.

 - it should come with build tooling checks that ensure that
   CFI annotations are sensible. We've seen such efforts from
   the framepointer side, and there's no reason it couldn't be
   done on the dwarf side.

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: Frédéric Weisbecker <fweisbec@gmail.com
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
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>
2015-06-02 07:57:48 +02:00
Ingo Molnar
fcbc99c403 x86/fpu: Split out fpu/signal.h from fpu/internal.h for signal frame handling functions
Most of the FPU does not use them, so split it out and include
them in signal.c and ia32_signal.c

Also fix header file dependency assumption in fpu/core.c.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:48:05 +02:00
Ingo Molnar
82c0e45eb5 x86/fpu: Move the signal frame handling code closer to each other
Consolidate more signal frame related functions:

   text      data    bss     dec       filename
   14108070  2575280 1634304 18317654  vmlinux.before
   14107944  2575344 1634304 18317592  vmlinux.after

Also, while moving it, rename alloc_mathframe() to fpu__alloc_mathframe().

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:48:04 +02:00
Ingo Molnar
9dfe99b755 x86/fpu: Rename restore_xstate_sig() to fpu__restore_sig()
restore_xstate_sig() is a misnomer: it's not limited to 'xstate' at all,
it is the high level 'restore FPU state from a signal frame' function
that works with all legacy FPU formats as well.

Rename it (and its helper) accordingly, and also move it to the
fpu__*() namespace.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:48:04 +02:00
Ingo Molnar
c8e1404120 x86/fpu: Rename save_xstate_sig() to copy_fpstate_to_sigframe()
Standardize the naming of save_xstate_sig() by renaming it to
copy_fpstate_to_sigframe(): this tells us at a glance that
the function copies an FPU fpstate to a signal frame.

This naming also follows the naming of copy_fpregs_to_fpstate().

Don't put 'xstate' into the name: since this is a generic name,
it's expected that the function is able to handle xstate frames
as well, beyond legacy frames.

xstate used to be the odd case in the x86 FPU code - now it's the
common case.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:48:01 +02:00
Ingo Molnar
78f7f1e54b x86/fpu: Rename fpu-internal.h to fpu/internal.h
This unifies all the FPU related header files under a unified, hiearchical
naming scheme:

 - asm/fpu/types.h:      FPU related data types, needed for 'struct task_struct',
                         widely included in almost all kernel code, and hence kept
                         as small as possible.

 - asm/fpu/api.h:        FPU related 'public' methods exported to other subsystems.

 - asm/fpu/internal.h:   FPU subsystem internal methods

 - asm/fpu/xsave.h:      XSAVE support internal methods

(Also standardize the header guard in asm/fpu/internal.h.)

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:31 +02:00
Ingo Molnar
c5bedc6847 x86/fpu: Get rid of PF_USED_MATH usage, convert it to fpu->fpstate_active
Introduce a simple fpu->fpstate_active flag in the fpu context data structure
and use that instead of PF_USED_MATH in task->flags.

Testing for this flag byte should be slightly more efficient than
testing a bit in a bitmask, but the main advantage is that most
FPU functions can now be performed on a 'struct fpu' alone, they
don't need access to 'struct task_struct' anymore.

There's a slight linecount increase, mostly due to the 'fpu' local
variables and due to extra comments. The local variables will go away
once we move most of the FPU methods to pure 'struct fpu' parameters.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:25 +02:00
Ingo Molnar
4c1384100e x86/fpu: Open code PF_USED_MATH usages
PF_USED_MATH is used directly, but also in a handful of helper inlines.

To ease the elimination of PF_USED_MATH, convert all inline helpers
to open-coded PF_USED_MATH usage.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:24 +02:00
Ingo Molnar
f89e32e0a3 x86/fpu: Fix header file dependencies of fpu-internal.h
Fix a minor header file dependency bug in asm/fpu-internal.h: it
relies on i387.h but does not include it. All users of fpu-internal.h
included it explicitly.

Also remove unnecessary includes, to reduce compilation time.

This also makes it easier to use it as a standalone header file
for FPU internals, such as an upcoming C module in arch/x86/kernel/fpu/.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:16 +02:00
Denys Vlasenko
3a23208e69 x86/entry: Define 'cpu_current_top_of_stack' for 64-bit code
32-bit code has PER_CPU_VAR(cpu_current_top_of_stack).
64-bit code uses somewhat more obscure: PER_CPU_VAR(cpu_tss + TSS_sp0).

Define the 'cpu_current_top_of_stack' macro on CONFIG_X86_64
as well so that the PER_CPU_VAR(cpu_current_top_of_stack)
expression can be used in both 32-bit and 64-bit code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1429889495-27850-3-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 13:50:02 +02:00
Denys Vlasenko
63332a8455 x86/entry: Stop using PER_CPU_VAR(kernel_stack)
PER_CPU_VAR(kernel_stack) is redundant:

  - On the 64-bit build, we can use PER_CPU_VAR(cpu_tss + TSS_sp0).
  - On the 32-bit build, we can use PER_CPU_VAR(cpu_current_top_of_stack).

PER_CPU_VAR(kernel_stack) will be deleted by a separate change.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1429889495-27850-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 13:43:52 +02:00
Ingo Molnar
7ae383be81 Merge branch 'linus' into x86/asm, before applying dependent patch
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 13:33:33 +02:00
Andy Lutomirski
61f01dd941 x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue
AMD CPUs don't reinitialize the SS descriptor on SYSRET, so SYSRET with
SS == 0 results in an invalid usermode state in which SS is apparently
equal to __USER_DS but causes #SS if used.

Work around the issue by setting SS to __KERNEL_DS __switch_to, thus
ensuring that SYSRET never happens with SS set to NULL.

This was exposed by a recent vDSO cleanup.

Fixes: e7d6eefaaa x86/vdso32/syscall.S: Do not load __USER32_DS to %ss
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-26 17:57:38 -07:00
Denys Vlasenko
3f5159a922 x86/asm/entry/32: Update -ENOSYS handling to match the 64-bit logic
Recently Andy changed the 64-bit syscall logic so that
pt_regs->ax is initially set to -ENOSYS, and on syscall exit,
it is updated with the actual return value. This simplified
the logic there.

This patch does the same for 32-bit syscall entry points.

The check for %rax being too big is moved to be just before
the call instruction which dispatches execution through the
syscall table.

There is no way to accidentally skip this check now by jumping
to a label after it. This allows us to remove redundant checks
after ptrace et al.

If %rax is too big, we just skip over the (call, write %rax to
pt_regs->ax) instruction pair. pt_regs->ax remains set to -ENOSYS,
and it gets returned to userspace.

Similar to 64-bit code, this eliminates the "ia32_badsys" code path.

Run-tested.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1429632194-13445-2-git-send-email-dvlasenk@redhat.com
[ Changelog massage. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-22 08:41:44 +02:00
Andy Lutomirski
aac82d3191 x86, paravirt, xen: Remove the 64-bit ->irq_enable_sysexit() pvop
We don't use irq_enable_sysexit on 64-bit kernels any more.
Remove all the paravirt and Xen machinery to support it on
64-bit kernels.

Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
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: Denys Vlasenko <vda.linux@googlemail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/8a03355698fe5b94194e9e7360f19f91c1b2cf1f.1428100853.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-22 08:07:45 +02:00
Denys Vlasenko
0f90fb979d x86/asm/entry: Zero EXTRA_REGS for stub32_execve() too
The change which affected how execve clears EXTRA_REGS missed
32-bit execve syscalls.

Fix this by using 64-bit execve stub epilogue for them too.

Run-tested.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-3-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-09 10:31:24 +02:00
Brian Gerst
6a3713f001 x86/signal: Remove pax argument from restore_sigcontext
The 'pax' argument is unnecesary.  Instead, store the RAX value
directly in regs.

This pattern goes all the way back to 2.1.106pre1, when restore_sigcontext()
was changed to return an error code instead of EAX directly:

  https://git.kernel.org/cgit/linux/kernel/git/history/history.git/diff/arch/i386/kernel/signal.c?id=9a8f8b7ca3f319bd668298d447bdf32730e51174

In 2007 sigaltstack syscall support was added, where the return
value of restore_sigcontext() was changed to carry the memory-copying
failure code.

But instead of putting 'ax' into regs->ax directly, it was carried
in via a pointer and then returned, where the generic syscall return
code copied it to regs->ax.

So there was never any deeper reason for this suboptimal pattern, it
was simply never noticed after being introduced.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
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: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1428152303-17154-1-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-06 09:06:39 +02:00
Andy Lutomirski
4214a16b02 x86/asm/entry/64/compat: Use SYSRETL to return from compat mode SYSENTER
SYSEXIT is scary on 64-bit kernels -- SYSEXIT must be invoked
with usergs and IRQs on.  That means that we rely on STI to
correctly mask interrupts for one instruction.  This is okay by
itself, but the semantics with respect to NMIs are unclear.

Avoid the whole issue by using SYSRETL instead.  For background,
Intel CPUs don't allow SYSCALL from compat mode, but they do
allow SYSRETL back to compat mode.  Go figure.

To avoid doing too much at once, this doesn't revamp the calling
convention.  We still return with EBP, EDX, and ECX on the user
stack.

Oddly this seems to be 30 cycles or so faster.  Avoiding POPFQ
and STI will account for under half of that, I think, so my best
guess is that Intel just optimizes SYSRET much better than
SYSEXIT.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
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: Denys Vlasenko <vda.linux@googlemail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/57a0bf1b5230b2716a64ebe48e9bc1110f7ab433.1428019097.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-03 09:14:00 +02:00
Denys Vlasenko
4c9c0e919f x86/asm/entry/32: Use smaller PUSH instructions instead of MOV, to build 'pt_regs' on stack
This mimics the recent similar 64-bit change.
Saves ~110 bytes of code.

Patch was run-tested on 32 and 64 bits, Intel and AMD CPU.
I also looked at the diff of entry_64.o disassembly, to have
a different view of the changes.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1427821211-25099-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-01 13:17:38 +02:00
Denys Vlasenko
4ee8ec17ba x86/asm/entry/32: Make register zero-extension more prominent
There are a couple of syscall argument zero-extension instructions in
the 32-bit compat entry code, and it was mentioned that people keep
trying to optimize them out, introducing bugs.

Make them more visible, and add a "do not remove" comment.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1427452582-21624-3-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 12:27:57 +01:00
Denys Vlasenko
a232e3d558 x86/asm/entry/32: Update "interrupt off" comments
The existing comment has proven to be not very clear.

Replace it with a comment similar to the one we now have in the 64-bit
syscall entry point. (Three instances, one per 32-bit syscall entry).

In the INT80 entry point's CFI annotations, replace mysterious
expressions with numric constants. In this case, raw numbers
look more understandable.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1427452582-21624-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 12:27:57 +01:00
Ingo Molnar
dca5b52ad7 x86/asm/entry/64: Rename THREAD_INFO() to ASM_THREAD_INFO()
The THREAD_INFO() macro has a somewhat confusingly generic name,
defined in a generic .h C header file. It also does not make it
clear that it constructs a memory operand for use in assembly
code.

Rename it to ASM_THREAD_INFO() to make it all glaringly
obvious on first glance.

Acked-by: Borislav Petkov <bp@suse.de>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/20150324184442.GC14760@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-24 20:57:31 +01:00
Ingo Molnar
f9d71854b4 x86/asm/entry/64: Merge the field offset into the THREAD_INFO() macro
Before:

   TI_sysenter_return+THREAD_INFO(%rsp,3*8),%r10d

After:

   movl    THREAD_INFO(TI_sysenter_return, %rsp, 3*8), %r10d

to turn it into a clear thread_info accessor.

No code changed:

 md5:
   fb4cb2b3ce05d89940ca304efc8ff183  ia32entry.o.before.asm
   fb4cb2b3ce05d89940ca304efc8ff183  ia32entry.o.after.asm

   e39f2958a5d1300158e276e4f7663263  entry_64.o.before.asm
   e39f2958a5d1300158e276e4f7663263  entry_64.o.after.asm

Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/20150324184411.GB14760@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-24 20:57:31 +01:00
Denys Vlasenko
ef593260f0 x86/asm/entry: Get rid of KERNEL_STACK_OFFSET
PER_CPU_VAR(kernel_stack) was set up in a way where it points
five stack slots below the top of stack.

Presumably, it was done to avoid one "sub $5*8,%rsp"
in syscall/sysenter code paths, where iret frame needs to be
created by hand.

Ironically, none of them benefits from this optimization,
since all of them need to allocate additional data on stack
(struct pt_regs), so they still have to perform subtraction.

This patch eliminates KERNEL_STACK_OFFSET.

PER_CPU_VAR(kernel_stack) now points directly to top of stack.
pt_regs allocations are adjusted to allocate iret frame as well.
Hopefully we can merge it later with 32-bit specific
PER_CPU_VAR(cpu_current_top_of_stack) variable...

Net result in generated code is that constants in several insns
are changed.

This change is necessary for changing struct pt_regs creation
in SYSCALL64 code path from MOV to PUSH instructions.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1426785469-15125-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-24 19:42:38 +01:00
Denys Vlasenko
b3fe8ba320 x86/asm/entry/64: Change the THREAD_INFO() definition to not depend on KERNEL_STACK_OFFSET
This changes the THREAD_INFO() definition and all its callsites
so that they do not count stack position from
(top of stack - KERNEL_STACK_OFFSET), but from top of stack.

Semi-mysterious expressions THREAD_INFO(%rsp,RIP) - "why RIP??"
are now replaced by more logical THREAD_INFO(%rsp,SIZEOF_PTREGS)
- "calculate thread_info's address using information that
rsp is SIZEOF_PTREGS bytes below top of stack".

While at it, replace "(off)-THREAD_SIZE(reg)" with equivalent
"((off)-THREAD_SIZE)(reg)". The form without parentheses
falsely looks like we invoke THREAD_SIZE() macro.

Improve comment atop THREAD_INFO macro definition.

This patch does not change generated code (verified by objdump).

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1426785469-15125-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-24 19:42:37 +01:00
Brian Gerst
1daeaa3151 x86/asm/entry: Fix execve() and sigreturn() syscalls to always return via IRET
Both the execve() and sigreturn() family of syscalls have the
ability to change registers in ways that may not be compatabile
with the syscall path they were called from.

In particular, SYSRET and SYSEXIT can't handle non-default %cs and %ss,
and some bits in eflags.

These syscalls have stubs that are hardcoded to jump to the IRET path,
and not return to the original syscall path.

The following commit:

   76f5df43ca ("Always allocate a complete "struct pt_regs" on the kernel stack")

recently changed this for some 32-bit compat syscalls, but introduced a bug where
execve from a 32-bit program to a 64-bit program would fail because it still returned
via SYSRETL. This caused Wine to fail when built for both 32-bit and 64-bit.

This patch sets TIF_NOTIFY_RESUME for execve() and sigreturn() so
that the IRET path is always taken on exit to userspace.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
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>
Link: http://lkml.kernel.org/r/1426978461-32089-1-git-send-email-brgerst@gmail.com
[ Improved the changelog and comments. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-23 08:52:46 +01:00
Andy Lutomirski
24933b82c0 x86/asm/entry: Rename 'init_tss' to 'cpu_tss'
It has nothing to do with init -- there's only one TSS per cpu.

Other names considered include:

 - current_tss: Confusing because we never switch the tss.
 - singleton_tss: Too long.

This patch was generated with 's/init_tss/cpu_tss/g'.  Followup
patches will fix INIT_TSS and INIT_TSS_IST by hand.

Signed-off-by: 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: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/da29fb2a793e4f649d93ce2d1ed320ebe8516262.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-06 08:32:58 +01:00
Andy Lutomirski
9d0c914c60 x86/asm/entry/64/compat: Change the 32-bit sysenter code to use sp0
The ia32 sysenter code loaded the top of the kernel stack into
rsp by loading kernel_stack and then adjusting it.  It can be
simplified to just read sp0 directly.

This requires the addition of a new asm-offsets entry for sp0.

Signed-off-by: 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: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/88ff9006163d296a0665338585c36d9bfb85235d.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-06 08:32:58 +01:00
Denys Vlasenko
b3ab90b333 x86/asm/entry/64/compat: Use more readable constant
The last instance of "mysterious" SS+8 constant is replaced by
SIZEOF_PTREGS.

Message-Id: <1424822419-10267-1-git-send-email-dvlasenk@redhat.com>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/d35aeba3059407ac54f472ddcfbea767ff8916ac.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-04 22:50:52 +01:00
Denys Vlasenko
14f6e9532d x86/asm/entry/64/compat: Fold the IA32_ARG_FIXUP macro into its callers
Use of a small macro - one with conditional expansion - does
more harm than good. It obfuscates code, with minimal code
reuse.

For example, because of obfuscation it's not obvious that
in 'ia32_sysenter_target', we can optimize loading of r9 -
currently it is loaded with a detour through ebp.

This patch folds the IA32_ARG_FIXUP macro into its callers.

No code changes.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/4da092094cd78734384ac31e0d4ec1d8f69145a2.1424989793.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-04 22:50:52 +01:00