Commit Graph

10 Commits

Author SHA1 Message Date
Linus Torvalds da17702385 Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 paravirt updates from Ingo Molnar:
 "A handful of paravirt patching code enhancements to make it more
  robust against patching failures, and related cleanups and not so
  related cleanups - by Thomas Gleixner and myself"

* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/paravirt: Rename paravirt_patch_site::instrtype to paravirt_patch_site::type
  x86/paravirt: Standardize 'insn_buff' variable names
  x86/paravirt: Match paravirt patchlet field definition ordering to initialization ordering
  x86/paravirt: Replace the paravirt patch asm magic
  x86/paravirt: Unify the 32/64 bit paravirt patching code
  x86/paravirt: Detect over-sized patching bugs in paravirt_patch_call()
  x86/paravirt: Detect over-sized patching bugs in paravirt_patch_insns()
  x86/paravirt: Remove bogus extern declarations
2019-07-08 17:34:44 -07:00
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Ingo Molnar 1fc654cf6e x86/paravirt: Standardize 'insn_buff' variable names
We currently have 6 (!) separate naming variants to name temporary instruction
buffers that are used for code patching:

 - insnbuf
 - insnbuff
 - insn_buff
 - insn_buffer
 - ibuf
 - ibuffer

These are used as local variables, percpu fields and function parameters.

Standardize all the names to a single variant: 'insn_buff'.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-29 16:05:49 +02:00
Paul Bolle bb12d6740f x86/decoder: Use stderr if insn sanity test fails
If the instruction sanity test fails, it prints a "Failure" message to
stdout. Make this program behave like the rest of the build and print
that message to stderr.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
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/1477428965-20548-3-git-send-email-pebolle@tiscali.nl
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-26 08:41:06 +02:00
Dave Hansen 6ba48ff46f x86: Remove arbitrary instruction size limit in instruction decoder
The current x86 instruction decoder steps along through the
instruction stream but always ensures that it never steps farther
than the largest possible instruction size (MAX_INSN_SIZE).

The MPX code is now going to be doing some decoding of userspace
instructions.  We copy those from userspace in to the kernel and
they're obviously completely untrusted coming from userspace.  In
addition to the constraint that instructions can only be so long,
we also have to be aware of how long the buffer is that came in
from userspace.  This _looks_ to be similar to what the perf and
kprobes is doing, but it's unclear to me whether they are
affected.

The whole reason we need this is that it is perfectly valid to be
executing an instruction within MAX_INSN_SIZE bytes of an
unreadable page. We should be able to gracefully handle short
reads in those cases.

This adds support to the decoder to record how long the buffer
being decoded is and to refuse to "validate" the instruction if
we would have gone over the end of the buffer to decode it.

The kprobes code probably needs to be looked at here a bit more
carefully.  This patch still respects the MAX_INSN_SIZE limit
there but the kprobes code does look like it might be able to
be a bit more strict than it currently is.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: x86@kernel.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20141114153957.E6B01535@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-18 00:58:52 +01:00
Andrew Morton 55a6e622e6 arch/x86/tools/insn_sanity.c: Identify source of messages
The kernel build prints:

  Building modules, stage 2.
  TEST    posttest
  MODPOST 3821 modules
  TEST    posttest
 Success: decoded and checked 1000000 random instructions with 0
 errors (seed:0xaac4bc47)   CC      arch/x86/boot/a20.o
  CC      arch/x86/boot/cmdline.o
  AS      arch/x86/boot/copy.o
  HOSTCC  arch/x86/boot/mkcpustr
  CC      arch/x86/boot/cpucheck.o
  CC      arch/x86/boot/early_serial_console.o

which is irritating because you don't know what program is
proudly pronouncing its success.

So, as described in "console mode programming user interface
guidelines version 101" which doesn't exist, change this program
to identify the source of its messages.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-24 15:57:53 +01:00
Masami Hiramatsu 9dde9dc0a8 x86/tools: Add decoded instruction dump mode
Add instruction dump mode to insn_sanity tool for
checking decoder really decoded instructions.

This mode is enabled when passing double -v (-vv) to
insn_sanity. It is useful for who wants to check whether
the decoder can decode some instructions correctly.
e.g.
 $ echo 0f 73 10 11 | ./insn_sanity -y -vv -i -
 Instruction = {
        .prefixes = {
                .value = 0, bytes[] = {0, 0, 0, 0},
                .got = 1, .nbytes = 0},
        .rex_prefix = {
                .value = 0, bytes[] = {0, 0, 0, 0},
                .got = 1, .nbytes = 0},
        .vex_prefix = {
                .value = 0, bytes[] = {0, 0, 0, 0},
                .got = 1, .nbytes = 0},
        .opcode = {
                .value = 29455, bytes[] = {f, 73, 0, 0},
                .got = 1, .nbytes = 2},
        .modrm = {
                .value = 16, bytes[] = {10, 0, 0, 0},
                .got = 1, .nbytes = 1},
        .sib = {
                .value = 0, bytes[] = {0, 0, 0, 0},
                .got = 1, .nbytes = 0},
        .displacement = {
                .value = 0, bytes[] = {0, 0, 0, 0},
                .got = 1, .nbytes = 0},
        .immediate1 = {
                .value = 17, bytes[] = {11, 0, 0, 0},
                .got = 1, .nbytes = 1},
        .immediate2 = {
                .value = 0, bytes[] = {0, 0, 0, 0},
                .got = 0, .nbytes = 0},
        .attr = 44800, .opnd_bytes = 4, .addr_bytes = 8,
        .length = 4, .x86_64 = 1, .kaddr = 0x7fff0f7d9430}
 Success: decoded and checked 1 given instructions with 0 errors (seed:0x0)

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20111205120603.15475.91192.stgit@cloud
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 14:53:23 +01:00
Masami Hiramatsu e70825fc51 x86/tools: Fix insn_sanity message outputs
Fix x86 instruction decoder test to dump all error messages
to stderr and others to stdout.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20111205120550.15475.70149.stgit@cloud
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 14:53:19 +01:00
Masami Hiramatsu bfbe9015de x86/tools: Fix instruction decoder message output
Fix instruction decoder test (insn_sanity), so that
it doesn't show both info and error messages twice on
same instruction. (In that case, show only error message)

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20111205120545.15475.7928.stgit@cloud
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 14:53:17 +01:00
Masami Hiramatsu 1ec454baf1 x86, perf: Add a build-time sanity test to the x86 decoder
Add a sanity test of x86 insn decoder against a stream
of randomly generated input, at build time.

This test is also able to reproduce any bug that might
trigger by allowing the passing of random-seed and
iteration-number to the test, or by passing input
which has invalid byte code.

Changes in V2:
 - Code cleanup.
 - Show how to reproduce the error by insn_sanity test.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: acme@redhat.com
Cc: ming.m.lin@intel.com
Cc: robert.richter@amd.com
Cc: ravitillo@lbl.gov
Cc: yrl.pp-manager.tt@hitachi.com
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20111020140109.20938.92572.stgit@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10 12:38:51 +01:00