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Adrian Hunter 69db696bdb x86/insn: Fix PUSH instruction in x86 instruction decoder opcode map
[ Upstream commit 59162e0c11 ]

The x86 instruction decoder is used not only for decoding kernel
instructions. It is also used by perf uprobes (user space probes) and by
perf tools Intel Processor Trace decoding. Consequently, it needs to
support instructions executed by user space also.

Opcode 0x68 PUSH instruction is currently defined as 64-bit operand size
only i.e. (d64). That was based on Intel SDM Opcode Map. However that is
contradicted by the Instruction Set Reference section for PUSH in the
same manual.

Remove 64-bit operand size only annotation from opcode 0x68 PUSH
instruction.

Example:

  $ cat pushw.s
  .global  _start
  .text
  _start:
          pushw   $0x1234
          mov     $0x1,%eax   # system call number (sys_exit)
          int     $0x80
  $ as -o pushw.o pushw.s
  $ ld -s -o pushw pushw.o
  $ objdump -d pushw | tail -4
  0000000000401000 <.text>:
    401000:       66 68 34 12             pushw  $0x1234
    401004:       b8 01 00 00 00          mov    $0x1,%eax
    401009:       cd 80                   int    $0x80
  $ perf record -e intel_pt//u ./pushw
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.014 MB perf.data ]

 Before:

  $ perf script --insn-trace=disasm
  Warning:
  1 instruction trace errors
           pushw   10349 [000] 10586.869237014:            401000 [unknown] (/home/ahunter/git/misc/rtit-tests/pushw)           pushw $0x1234
           pushw   10349 [000] 10586.869237014:            401006 [unknown] (/home/ahunter/git/misc/rtit-tests/pushw)           addb %al, (%rax)
           pushw   10349 [000] 10586.869237014:            401008 [unknown] (/home/ahunter/git/misc/rtit-tests/pushw)           addb %cl, %ch
           pushw   10349 [000] 10586.869237014:            40100a [unknown] (/home/ahunter/git/misc/rtit-tests/pushw)           addb $0x2e, (%rax)
   instruction trace error type 1 time 10586.869237224 cpu 0 pid 10349 tid 10349 ip 0x40100d code 6: Trace doesn't match instruction

 After:

  $ perf script --insn-trace=disasm
             pushw   10349 [000] 10586.869237014:            401000 [unknown] (./pushw)           pushw $0x1234
             pushw   10349 [000] 10586.869237014:            401004 [unknown] (./pushw)           movl $1, %eax

Fixes: eb13296cfa ("x86: Instruction decoder API")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240502105853.5338-3-adrian.hunter@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-16 13:39:31 +02:00
arch x86/insn: Fix PUSH instruction in x86 instruction decoder opcode map 2024-06-16 13:39:31 +02:00
block blk-iocost: avoid out of bounds shift 2024-05-17 11:50:54 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:22:01 +02:00
crypto Revert "crypto: api - Disallow identical driver names" 2024-05-02 16:24:47 +02:00
Documentation media: dt-bindings: ovti,ov2680: Fix the power supply names 2024-06-16 13:39:29 +02:00
drivers clk: qcom: mmcc-msm8998: fix venus clock issue 2024-06-16 13:39:31 +02:00
fs gfs2: Fix "ignore unlock failures after withdraw" 2024-06-16 13:39:20 +02:00
include drm/mipi-dsi: use correct return type for the DSC functions 2024-06-16 13:39:30 +02:00
init init/main.c: Fix potential static_command_line memory overflow 2024-04-27 17:05:28 +02:00
io_uring io_uring: ensure '0' is returned on file registration success 2024-04-10 16:19:37 +02:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:28:45 +01:00
kernel sched/fair: Add EAS checks before updating root_domain::overutilized 2024-06-16 13:39:18 +02:00
lib mm/slub, kunit: Use inverted data to corrupt kmem cache 2024-06-16 13:39:16 +02:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm x86/mm/pat: fix VM_PAT handling in COW mappings 2024-04-13 13:01:47 +02:00
net mptcp: SO_KEEPALIVE: fix getsockopt support 2024-06-16 13:39:26 +02:00
samples samples/hw_breakpoint: fix building without module unloading 2023-09-23 11:10:01 +02:00
scripts kbuild: Disable KCSAN for autogenerated *.mod.c intermediaries 2024-05-17 11:50:53 +02:00
security KEYS: trusted: Do not use WARN when encode fails 2024-05-25 16:20:18 +02:00
sound ASoC: kirkwood: Fix potential NULL dereference 2024-06-16 13:39:27 +02:00
tools x86/insn: Fix PUSH instruction in x86 instruction decoder opcode map 2024-06-16 13:39:31 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:27:15 +01:00
virt KVM: Always flush async #PF workqueue when vCPU is being destroyed 2024-04-10 16:18:34 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS trace: Relocate event helper files 2024-04-10 16:19:24 +02:00
Makefile Linux 5.15.160 2024-05-25 16:20:19 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.