blob: e7e5e88e1b822df4c5acff7744e9dfe474871315 [file] [log] [blame]
From 9aa56d861b279ac03654635f9342ffce787a1a6d Mon Sep 17 00:00:00 2001
From: Masami Hiramatsu <mhiramat@kernel.org>
Date: Wed, 22 Jan 2020 13:11:54 +0900
Subject: [PATCH] x86/decoder: Add TEST opcode to Group3-2
commit 8b7e20a7ba54836076ff35a28349dabea4cec48f upstream.
Add TEST opcode to Group3-2 reg=001b as same as Group3-1 does.
Commit
12a78d43de76 ("x86/decoder: Add new TEST instruction pattern")
added a TEST opcode assignment to f6 XX/001/XXX (Group 3-1), but did
not add f7 XX/001/XXX (Group 3-2).
Actually, this TEST opcode variant (ModRM.reg /1) is not described in
the Intel SDM Vol2 but in AMD64 Architecture Programmer's Manual Vol.3,
Appendix A.2 Table A-6. ModRM.reg Extensions for the Primary Opcode Map.
Without this fix, Randy found a warning by insn_decoder_test related
to this issue as below.
HOSTCC arch/x86/tools/insn_decoder_test
HOSTCC arch/x86/tools/insn_sanity
TEST posttest
arch/x86/tools/insn_decoder_test: warning: Found an x86 instruction decoder bug, please report this.
arch/x86/tools/insn_decoder_test: warning: ffffffff81000bf1: f7 0b 00 01 08 00 testl $0x80100,(%rbx)
arch/x86/tools/insn_decoder_test: warning: objdump says 6 bytes, but insn_get_length() says 2
arch/x86/tools/insn_decoder_test: warning: Decoded and checked 11913894 instructions with 1 failures
TEST posttest
arch/x86/tools/insn_sanity: Success: decoded and checked 1000000 random instructions with 0 errors (seed:0x871ce29c)
To fix this error, add the TEST opcode according to AMD64 APM Vol.3.
[ bp: Massage commit message. ]
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lkml.kernel.org/r/157966631413.9580.10311036595431878351.stgit@devnote2
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt
index 0a0e9112f284..5cb9f009f2be 100644
--- a/arch/x86/lib/x86-opcode-map.txt
+++ b/arch/x86/lib/x86-opcode-map.txt
@@ -909,7 +909,7 @@ EndTable
GrpTable: Grp3_2
0: TEST Ev,Iz
-1:
+1: TEST Ev,Iz
2: NOT Ev
3: NEG Ev
4: MUL rAX,Ev
diff --git a/tools/objtool/arch/x86/lib/x86-opcode-map.txt b/tools/objtool/arch/x86/lib/x86-opcode-map.txt
index 0a0e9112f284..5cb9f009f2be 100644
--- a/tools/objtool/arch/x86/lib/x86-opcode-map.txt
+++ b/tools/objtool/arch/x86/lib/x86-opcode-map.txt
@@ -909,7 +909,7 @@ EndTable
GrpTable: Grp3_2
0: TEST Ev,Iz
-1:
+1: TEST Ev,Iz
2: NOT Ev
3: NEG Ev
4: MUL rAX,Ev
--
2.7.4