Commit graph

21,488 commits

Author SHA1 Message Date
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
4416c5a6da x86/asm/entry/64: Do not TRACE_IRQS fast SYSRET64 path
SYSRET code path has a small irq-off block.
On this code path, TRACE_IRQS_ON can't be called right before
interrupts are enabled for real, we can't clobber registers
there. So current code does it earlier, in a safe place.

But with this, TRACE_IRQS_OFF/ON frames just two fast
instructions, which is ridiculous: now most of irq-off block is
_outside_ of the framing.

Do the same thing that we do on SYSCALL entry: do not track this
irq-off block, it is very small to ever cause noticeable irq
latency.

Be careful: make sure that "jnz int_ret_from_sys_call_irqs_off"
now does invoke TRACE_IRQS_OFF - move
int_ret_from_sys_call_irqs_off label before TRACE_IRQS_OFF.

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/1427821211-25099-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-01 13:17:38 +02:00
Bandan Das
4399c03c67 x86/apic: Remove verify_local_APIC()
__verify_local_APIC() is detritus from the early APIC days.
Its return value isn't used anywhere and the information it
prints when debug is enabled is already part of APIC
initialization messages printed to syslog. Off with it!

Signed-off-by: Bandan Das <bsd@redhat.com>
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>
Link: http://lkml.kernel.org/r/jpgy4mcsxsq.fsf@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-01 10:47:57 +02:00
Joe Perches
1d804d079a x86: Use bool function return values of true/false not 1/0
Use the normal return values for bool functions

Signed-off-by: Joe Perches <joe@perches.com>
Message-Id: <9f593eb2f43b456851cd73f7ed09654ca58fb570.1427759009.git.joe@perches.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-31 18:05:09 +02:00
Stephan Mueller
555fa17b2b crypto: sha-mb - mark Multi buffer SHA1 helper cipher
Flag all Multi buffer SHA1 helper ciphers as internal ciphers
to prevent them from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:13 +08:00
Stephan Mueller
4dda66f62e crypto: twofish_avx - mark Twofish AVX helper ciphers
Flag all Twofish AVX helper ciphers as internal ciphers to prevent
them from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:11 +08:00
Stephan Mueller
748be1f1bf crypto: serpent_sse2 - mark Serpent SSE2 helper ciphers
Flag all Serpent SSE2 helper ciphers as internal ciphers to prevent
them from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:10 +08:00
Stephan Mueller
65aed53941 crypto: serpent_avx - mark Serpent AVX helper ciphers
Flag all Serpent AVX helper ciphers as internal ciphers to prevent
them from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:10 +08:00
Stephan Mueller
f82419acd8 crypto: serpent_avx2 - mark Serpent AVX2 helper ciphers
Flag all Serpent AVX2 helper ciphers as internal ciphers to prevent
them from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:09 +08:00
Stephan Mueller
e69b8a46ca crypto: cast6_avx - mark CAST6 helper ciphers
Flag all CAST6 helper ciphers as internal ciphers to prevent them
from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:09 +08:00
Stephan Mueller
7d2c31dd70 crypto: camellia_aesni_avx - mark AVX Camellia helper ciphers
Flag all AVX Camellia helper ciphers as internal ciphers to prevent
them from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:08 +08:00
Stephan Mueller
680574e8b3 crypto: cast5_avx - mark CAST5 helper ciphers
Flag all CAST5 helper ciphers as internal ciphers to prevent them
from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:08 +08:00
Stephan Mueller
a62356a978 crypto: camellia_aesni_avx2 - mark AES-NI Camellia helper ciphers
Flag all AES-NI Camellia helper ciphers as internal ciphers to
prevent them from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:07 +08:00
Stephan Mueller
6a9b52b7fa crypto: clmulni - mark ghash clmulni helper ciphers
Flag all ash clmulni helper ciphers as internal ciphers to prevent them
from being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:06 +08:00
Stephan Mueller
eabdc320ec crypto: aesni - mark AES-NI helper ciphers
Flag all AES-NI helper ciphers as internal ciphers to prevent them from
being called by normal users.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-31 21:21:05 +08:00
Ingo Molnar
55474c48b4 x86/asm/entry: Remove user_mode_ignore_vm86()
user_mode_ignore_vm86() can be used instead of user_mode(), in
places where we have already done a v8086_mode() security
check of ptregs.

But doing this check in the wrong place would be a bug that
could result in security problems, and also the naming still
isn't very clear.

Furthermore, it only affects 32-bit kernels, while most
development happens on 64-bit kernels.

If we replace them with user_mode() checks then the cost is only
a very minor increase in various slowpaths:

   text             data   bss     dec              hex    filename
   10573391         703562 1753042 13029995         c6d26b vmlinux.o.before
   10573423         703562 1753042 13030027         c6d28b vmlinux.o.after

So lets get rid of this distinction once and for all.

Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
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/20150329090233.GA1963@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 11:45:19 +02:00
Andy Lutomirski
115db5c68b x86/vdso: Remove x32 intermediates during 'make clean'
The existing clean-files rule was missing vdsox32.so and
vdsox32.so.dbg.  We should really rename the intermediates to
allow a single rule to get them all.

Also-reported-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Link: http://lkml.kernel.org/r/7fa2ad4a63bc6f52e214125900d54165ef06cc10.1427482099.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 10:45:15 +02:00
Andrey Skvortsov
ef37507d99 x86/vdso: Teach 'make clean' to remove generated vdso-image-*.c files
After 'make clean' the following files were left in arch/x86/vdso/:

  vdso-image-32-int80.c
  vdso-image-32-syscall.c
  vdso-image-32-sysenter.c

These file are generated during the build process and are present
in .gitignore, so remove them.

Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Link: http://lkml.kernel.org/r/f85bb7ef6f8c6f6aa4bf422348018c84321454f8.1427482099.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 10:45:15 +02:00
Denys Vlasenko
e7d6eefaaa x86/vdso32/syscall.S: Do not load __USER32_DS to %ss
This vDSO code only gets used by 64-bit kernels, not 32-bit ones.

On 64-bit kernels, the data segment is the same for 32-bit and
64-bit userspace, and the SYSRET instruction loads %ss with its
selector.

So there's no need to repeat it by hand. Segment loads are somewhat
expensive: tens of cycles.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
[ Removed unnecessary comment. ]
Signed-off-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/63da6d778f69fd0f1345d9287f6764d58be519fa.1427482099.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 10:45:15 +02:00
Tommi Kyntola
0a4f59d6e0 x86/vdso: Fix the x86 vdso2c tool includes
The build-time tool arch/x86/vdso/vdso2c.c includes <linux/elf.h>,
but cannot find it, unless the build host happens to provide it.

It should be reading the uapi linux/elf.h

This build regression came along with the vdso2c changes between
v3.15 and v3.16.

Signed-off-by: Tommi Kyntola <tommi.kyntola@gmail.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/1525002.3cJ7BySVpA@musta
Link: http://lkml.kernel.org/r/efe1ec29eda830b1d0030882706f3dac99ce1f73.1427482099.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 10:45:14 +02:00
Hector Marco-Gisbert
4e26d11f52 x86/mm: Improve AMD Bulldozer ASLR workaround
The ASLR implementation needs to special-case AMD F15h processors by
clearing out bits [14:12] of the virtual address in order to avoid I$
cross invalidations and thus performance penalty for certain workloads.
For details, see:

  dfb09f9b7a ("x86, amd: Avoid cache aliasing penalties on AMD family 15h")

This special case reduces the mmapped file's entropy by 3 bits.

The following output is the run on an AMD Opteron 62xx class CPU
processor under x86_64 Linux 4.0.0:

  $ for i in `seq 1 10`; do cat /proc/self/maps | grep "r-xp.*libc" ; done
  b7588000-b7736000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b7570000-b771e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b75d0000-b777e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b75b0000-b775e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b7578000-b7726000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  ...

Bits [12:14] are always 0, i.e. the address always ends in 0x8000 or
0x0000.

32-bit systems, as in the example above, are especially sensitive
to this issue because 32-bit randomness for VA space is 8 bits (see
mmap_rnd()). With the Bulldozer special case, this diminishes to only 32
different slots of mmap virtual addresses.

This patch randomizes per boot the three affected bits rather than
setting them to zero. Since all the shared pages have the same value
at bits [12..14], there is no cache aliasing problems. This value gets
generated during system boot and it is thus not known to a potential
remote attacker. Therefore, the impact from the Bulldozer workaround
gets diminished and ASLR randomness increased.

More details at:

  http://hmarco.org/bugs/AMD-Bulldozer-linux-ASLR-weakness-reducing-mmaped-files-by-eight.html

Original white paper by AMD dealing with the issue:

  http://developer.amd.com/wordpress/media/2012/10/SharedL1InstructionCacheonAMD15hCPU.pdf

Mentored-by: Ismael Ripoll <iripoll@disca.upv.es>
Signed-off-by: Hector Marco-Gisbert <hecmargi@upv.es>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan-Simon <dl9pf@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-fsdevel@vger.kernel.org
Link: http://lkml.kernel.org/r/1427456301-3764-1-git-send-email-hecmargi@upv.es
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 10:01:17 +02:00
Michael S. Tsirkin
46423ffaf4 x86/microcode/amd: Drop the pci_ids.h dependency
This file doesn't use any macros from pci_ids.h anymore, drop the include.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1427635734-24786-80-git-send-email-mst@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 09:54:32 +02:00
Denys Vlasenko
a3675b32aa x86/asm/entry/64: Do not GET_THREAD_INFO() too early
At exit_intr, we GET_THREAD_INFO(%rcx) and then jump to
retint_kernel if saved CS was from kernel. But the code at
retint_kernel doesn't need %rcx.

Move GET_THREAD_INFO(%rcx) down, after CS check and branch.

While at it, remove "has a correct top of stack" comment.
After recent changes which eliminated FIXUP_TOP_OF_STACK,
we always have a correct pt_regs layout.

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/1427738975-7391-5-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 09:31:11 +02:00
Denys Vlasenko
627276cb55 x86/asm/entry/64: Move retint_kernel code block closer to its user
The "retint_kernel" code block is misplaced. Since its logical
continuation is "retint_restore_args", it is more natural to
place it above that label. This also makes two jumps "short".

This change only moves code block around, without changing
logic.

This enables the next simplification: making
"retint_restore_args" label a local numeric one.

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/1427738975-7391-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 09:31:11 +02:00
Ingo Molnar
c5e77f5216 Linux 4.0-rc6
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJVGHwjAAoJEHm+PkMAQRiG8rcIAJ6cEJ6mbqLpyz5XrGf4yNp0
 +wG/QlEpT8rgrxe9wSjB3lfW3kR2Pe69b9fVVCdiklygdkmva5vfmDrVGGzYfe3M
 QrFSSlMVBplvh6IiM/L1mVMtr3DSmCO23YZZ9R5b7FoEYatNHRpNWBCBpuXpd4aD
 sLuIvO3L/S7LqeOAFkkYWv6AuL9umicmjR8u+nsmCSRJom7At/aJ6R66WIp9vxho
 Rn7r6wcUk6B2Q/gYNjdSE8SIwdyKhuBGyvqQ9U9s6Btg9DQfM/b0vG5kw9hqeAq/
 9445jqVDP1whA2vz6GjnvltidxrqRvuDPBwzOnFmY5U+KZz4lS3x2mnWAAJ3xWs=
 =TqVJ
 -----END PGP SIGNATURE-----

Merge tag 'v4.0-rc6' into timers/core, before applying new patches

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 09:08:13 +02:00
Eugene Korenevsky
2f729b10bb KVM: remove useless check of "ret" variable prior to returning the same value
A trivial code cleanup. This `if` is redundant.

Signed-off-by: Eugene Korenevsky <ekorenevsky@gmail.com>
Message-Id: <20150328222717.GA6508@gnote>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-30 16:57:15 +02:00
Nadav Amit
b32a991800 KVM: x86: Remove redundant definitions
Some constants are redfined in emulate.c. Avoid it.

s/SELECTOR_RPL_MASK/SEGMENT_RPL_MASK
s/SELECTOR_TI_MASK/SEGMENT_TI_MASK

No functional change.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427635984-8113-3-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-30 16:46:42 +02:00
Nadav Amit
0efb04406d KVM: x86: removing redundant eflags bits definitions
The eflags are redefined (using other defines) in emulate.c.
Use the definition from processor-flags.h as some mess already started.
No functional change.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427635984-8113-2-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-30 16:46:37 +02:00
Nadav Amit
900efe200e KVM: x86: BSF and BSR emulation change register unnecassarily
If the source of BSF and BSR is zero, the destination register should not
change. That is how real hardware behaves.  If we set the destination even with
the same value that we had before, we may clear bits [63:32] unnecassarily.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-4-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-30 16:46:11 +02:00
Nadav Amit
6fd8e12757 KVM: x86: POPA emulation may not clear bits [63:32]
POPA should assign the values to the registers as usual registers are assigned.
In other words, 32-bits register assignments should clear bits [63:32] of the
register.

Split the code of register assignments that will be used by future changes as
well.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-3-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-30 16:46:03 +02:00
Nadav Amit
b91aa14d95 KVM: x86: CMOV emulation on legacy mode is wrong
On legacy mode CMOV emulation should still clear bits [63:32] even if the
assignment is not done. The previous fix 140bad89fd ("KVM: x86: emulation of
dword cmov on long-mode should clear [63:32]") was incomplete.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-2-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-30 16:45:50 +02:00
Petr Matousek
2dccb4cdbf kvm: x86: i8259: return initialized data on invalid-size read
If data is read from PIC with invalid access size, the return data stays
uninitialized even though success is returned.

Fix this by always initializing the data.

Signed-off-by: Petr Matousek <pmatouse@redhat.com>
Reported-by: Nadav Amit <nadav.amit@gmail.com>
Message-Id: <20150311111609.GG8544@dhcp-25-225.brq.redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-30 16:40:07 +02:00
Linus Torvalds
7fc377ecf4 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Ingo Molnar:
 "Fix x86 syscall exit code bug that resulted in spurious non-execution
  of TIF-driven user-return worklets, causing big trouble for things
  like KVM that rely on user notifiers for correctness of their vcpu
  model, causing crashes like double faults"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asm/entry: Check for syscall exit work with IRQs disabled
2015-03-28 11:25:04 -07:00
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
Denys Vlasenko
27be87c5d5 x86/asm/entry/64: Add missing CFI annotation
This is a missing bit of the recent MOV-to-PUSH conversion.

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/1427452582-21624-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 12:27:57 +01:00
Denys Vlasenko
487d1edb9a x86/asm/entry/64: Fix comment about SYSENTER MSRs
The comment is ancient, it dates to the time when only AMD's
x86_64 implementation existed. AMD wasn't (and still isn't)
supporting SYSENTER, so these writes were "just in case" back
then.

This has changed: Intel's x86_64 appeared, and Intel does
support SYSENTER in long mode. "Some future 64-bit CPU" is here
already.

The code may appear "buggy" for AMD as it stands, since
MSR_IA32_SYSENTER_EIP is only 32-bit for AMD CPUs. Writing a
kernel function's address to it would drop high bits. Subsequent
use of this MSR for branch via SYSENTER seem to allow user to
transition to CPL0 while executing his code. Scary, eh?

Explain why that is not a bug: because SYSENTER insn would not
work on AMD CPU.

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/1427453956-21931-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 12:23:16 +01:00
Peter Zijlstra
34f439278c perf: Add per event clockid support
While thinking on the whole clock discussion it occurred to me we have
two distinct uses of time:

 1) the tracking of event/ctx/cgroup enabled/running/stopped times
    which includes the self-monitoring support in struct
    perf_event_mmap_page.

 2) the actual timestamps visible in the data records.

And we've been conflating them.

The first is all about tracking time deltas, nobody should really care
in what time base that happens, its all relative information, as long
as its internally consistent it works.

The second however is what people are worried about when having to
merge their data with external sources. And here we have the
discussion on MONOTONIC vs MONOTONIC_RAW etc..

Where MONOTONIC is good for correlating between machines (static
offset), MONOTNIC_RAW is required for correlating against a fixed rate
hardware clock.

This means configurability; now 1) makes that hard because it needs to
be internally consistent across groups of unrelated events; which is
why we had to have a global perf_clock().

However, for 2) it doesn't really matter, perf itself doesn't care
what it writes into the buffer.

The below patch makes the distinction between these two cases by
adding perf_event_clock() which is used for the second case. It
further makes this configurable on a per-event basis, but adds a few
sanity checks such that we cannot combine events with different clocks
in confusing ways.

And since we then have per-event configurability we might as well
retain the 'legacy' behaviour as a default.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 10:13:22 +01:00
Ingo Molnar
b381e63b48 Merge branch 'perf/core' into perf/timer, before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 10:10:47 +01:00
Ingo Molnar
4e6d7c2aa9 Merge branch 'timers/core' into perf/timer, to apply dependent patch
An upcoming patch will depend on tai_ns() and NMI-safe ktime_get_raw_fast(),
so merge timers/core here in a separate topic branch until it's all cooked
and timers/core is merged upstream.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 10:09:21 +01:00
Ingo Molnar
4bfe186dbe Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

  - Documentation updates.

  - Changes permitting use of call_rcu() and friends very early in
    boot, for example, before rcu_init() is invoked.

  - Miscellaneous fixes.

  - Add in-kernel API to enable and disable expediting of normal RCU
    grace periods.

  - Improve RCU's handling of (hotplug-) outgoing CPUs.

    Note: ARM support is lagging a bit here, and these improved
    diagnostics might generate (harmless) splats.

  - NO_HZ_FULL_SYSIDLE fixes.

  - Tiny RCU updates to make it more tiny.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 10:04:06 +01:00
Denys Vlasenko
aa6d9a128b x86/irq/tracing: Do not save callee-preserved registers around lockdep_sys_exit_thunk
Internally, lockdep_sys_exit_thunk saves callee-clobbered
registers, and calls a C function, lockdep_sys_exit. Thus,
callee-preserved registers won't be mangled, there is no need to
save them.

Patch was 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/1427314468-12763-4-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 10:01:49 +01:00
Denys Vlasenko
7dc7cc0780 x86/irq/tracing: Fold ARCH_LOCKDEP_SYS_EXIT defines into their users
There is no need to have an extra level of macro indirection
here.

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/1427314468-12763-3-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 10:01:49 +01:00
Denys Vlasenko
40e2ec657d x86/irq/tracing: Move ARCH_LOCKDEP_SYS_EXIT defines closer to their users
This change simply moves defines around (even if it's not
obvious in a patch form). Nothing is changed.

This is a preparation for folding ARCH_LOCKDEP_SYS_EXIT defines
into their users.

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/1427314468-12763-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 10:01:48 +01:00
Denys Vlasenko
47eb582e70 x86/asm/entry/64: Use smaller instructions
The $AUDIT_ARCH_X86_64 parameter to syscall_trace_enter_phase1/2
is a 32-bit constant, loading it with 32-bit MOV produces 5-byte
insn instead of 10-byte MOVABS one.

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/1427303896-24023-3-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 09:57:06 +01:00
Denys Vlasenko
146b2b097d x86/asm/entry/64: Use better label name, fix comments
A named label "ret_from_sys_call" implies that there are jumps
to this location from elsewhere, as happens with many other
labels in this file.

But this label is used only by the JMP a few insns above.
To make that obvious, use local numeric label instead.

Improve comments:

"and return regs->ax" isn't too informative. We always return
regs->ax.

The comment suggesting that it'd be cool to use rip relative
addressing for CALL is deleted. It's unclear why that would be
an improvement - we aren't striving to use position-independent
code here. PIC code here would require something like LEA
sys_call_table(%rip),reg + CALL *(reg,%rax*8)...

"iret frame is also incomplete" is no longer true, fix that too.

Also fix typo in 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/1427303896-24023-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 09:57:05 +01:00
David Ahern
9332d250b4 perf/x86: Remove redundant calls to perf_pmu_{dis|en}able()
perf_pmu_disable() is called before pmu->add() and perf_pmu_enable() is called
afterwards. No need to call these inside of x86_pmu_add() as well.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1424281543-67335-1-git-send-email-dsahern@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 09:49:44 +01:00
Ingo Molnar
936c663aed Merge branch 'perf/x86' into perf/core, because it's ready
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 09:46:19 +01:00
Ingo Molnar
072e5a1cfa Merge branch 'perf/urgent' into perf/core, to pick up fixes and to refresh the tree
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 09:46:03 +01:00
Peter Zijlstra
876e78818d time: Rename timekeeper::tkr to timekeeper::tkr_mono
In preparation of adding another tkr field, rename this one to
tkr_mono. Also rename tk_read_base::base_mono to tk_read_base::base,
since the structure is not specific to CLOCK_MONOTONIC and the mono
name got added to the tk_read_base instance.

Lots of trivial churn.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20150319093400.344679419@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-27 09:45:06 +01:00