kernel_optimize_test/arch/x86/lib
Masami Hiramatsu 12a78d43de x86/decoder: Add new TEST instruction pattern
The kbuild test robot reported this build warning:

  Warning: arch/x86/tools/test_get_len found difference at <jump_table>:ffffffff8103dd2c

  Warning: ffffffff8103dd82: f6 09 d8 testb $0xd8,(%rcx)
  Warning: objdump says 3 bytes, but insn_get_length() says 2
  Warning: decoded and checked 1569014 instructions with 1 warnings

This sequence seems to be a new instruction not in the opcode map in the Intel SDM.

The instruction sequence is "F6 09 d8", means Group3(F6), MOD(00)REG(001)RM(001), and 0xd8.
Intel SDM vol2 A.4 Table A-6 said the table index in the group is "Encoding of Bits 5,4,3 of
the ModR/M Byte (bits 2,1,0 in parenthesis)"

In that table, opcodes listed by the index REG bits as:

  000         001       010 011  100        101        110         111
 TEST Ib/Iz,(undefined),NOT,NEG,MUL AL/rAX,IMUL AL/rAX,DIV AL/rAX,IDIV AL/rAX

So, it seems TEST Ib is assigned to 001.

Add the new pattern.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
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
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-24 08:36:12 +01:00
..
.gitignore
atomic64_32.c
atomic64_386_32.S
atomic64_cx8_32.S
cache-smp.c
checksum_32.S
clear_page_64.S
cmdline.c
cmpxchg8b_emu.S
cmpxchg16b_emu.S
copy_page_64.S
copy_user_64.S
cpu.c
csum-copy_64.S
csum-partial_64.c
csum-wrappers_64.c
delay.c
getuser.S
hweight.S
inat.c
insn-eval.c
insn.c
iomap_copy_64.S
kaslr.c
Makefile
memcpy_32.c
memcpy_64.S
memmove_64.S
memset_64.S
misc.c
mmx_32.c
msr-reg-export.c
msr-reg.S
msr-smp.c
msr.c
putuser.S
rwsem.S
string_32.c
strstr_32.c
usercopy_32.c
usercopy_64.c
usercopy.c
x86-opcode-map.txt