6.12-stable review patch. If anyone has any objections, please let me know.
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From: Kirill A. Shutemov kirill.shutemov@linux.intel.com
commit 85fd85bc025a525354acb2241beb3c5387c551ec upstream.
insn_decoder_test found a problem with decoding APX CTEST instructions:
Found an x86 instruction decoder bug, please report this. ffffffff810021df 62 54 94 05 85 ff ctestneq objdump says 6 bytes, but insn_get_length() says 5
It happens because x86-opcode-map.txt doesn't specify arguments for the instruction and the decoder doesn't expect to see ModRM byte.
Fixes: 690ca3a3067f ("x86/insn: Add support for APX EVEX instructions to the opcode map") Signed-off-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar mingo@kernel.org Cc: H. Peter Anvin hpa@zytor.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: stable@vger.kernel.org # v6.10+ Link: https://lore.kernel.org/r/20250423065815.2003231-1-kirill.shutemov@linux.int... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/lib/x86-opcode-map.txt | 4 ++-- tools/arch/x86/lib/x86-opcode-map.txt | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-)
--- a/arch/x86/lib/x86-opcode-map.txt +++ b/arch/x86/lib/x86-opcode-map.txt @@ -996,8 +996,8 @@ AVXcode: 4 83: Grp1 Ev,Ib (1A),(es) # CTESTSCC instructions are: CTESTB, CTESTBE, CTESTF, CTESTL, CTESTLE, CTESTNB, CTESTNBE, CTESTNL, # CTESTNLE, CTESTNO, CTESTNS, CTESTNZ, CTESTO, CTESTS, CTESTT, CTESTZ -84: CTESTSCC (ev) -85: CTESTSCC (es) | CTESTSCC (66),(es) +84: CTESTSCC Eb,Gb (ev) +85: CTESTSCC Ev,Gv (es) | CTESTSCC Ev,Gv (66),(es) 88: POPCNT Gv,Ev (es) | POPCNT Gv,Ev (66),(es) 8f: POP2 Bq,Rq (000),(11B),(ev) a5: SHLD Ev,Gv,CL (es) | SHLD Ev,Gv,CL (66),(es) --- a/tools/arch/x86/lib/x86-opcode-map.txt +++ b/tools/arch/x86/lib/x86-opcode-map.txt @@ -996,8 +996,8 @@ AVXcode: 4 83: Grp1 Ev,Ib (1A),(es) # CTESTSCC instructions are: CTESTB, CTESTBE, CTESTF, CTESTL, CTESTLE, CTESTNB, CTESTNBE, CTESTNL, # CTESTNLE, CTESTNO, CTESTNS, CTESTNZ, CTESTO, CTESTS, CTESTT, CTESTZ -84: CTESTSCC (ev) -85: CTESTSCC (es) | CTESTSCC (66),(es) +84: CTESTSCC Eb,Gb (ev) +85: CTESTSCC Ev,Gv (es) | CTESTSCC Ev,Gv (66),(es) 88: POPCNT Gv,Ev (es) | POPCNT Gv,Ev (66),(es) 8f: POP2 Bq,Rq (000),(11B),(ev) a5: SHLD Ev,Gv,CL (es) | SHLD Ev,Gv,CL (66),(es)