From: tip-bot for Masami Hiramatsu <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: fengguang.wu@intel.com, torvalds@linux-foundation.org,
hpa@zytor.com, stable@vger.kernel.org, tglx@linutronix.de,
mhiramat@kernel.org, mingo@kernel.org,
gregkh@linuxfoundation.org, peterz@infradead.org
Subject: [tip:x86/urgent] x86/decoder: Add new TEST instruction pattern
Date: Thu, 23 Nov 2017 23:39:46 -0800 [thread overview]
Message-ID: <tip-12a78d43de767eaf8fb272facb7a7b6f2dc6a9df@git.kernel.org> (raw)
Commit-ID: 12a78d43de767eaf8fb272facb7a7b6f2dc6a9df
Gitweb: https://git.kernel.org/tip/12a78d43de767eaf8fb272facb7a7b6f2dc6a9df
Author: Masami Hiramatsu <mhiramat@kernel.org>
AuthorDate: Fri, 24 Nov 2017 13:56:30 +0900
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 24 Nov 2017 08:36:12 +0100
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>
---
arch/x86/lib/x86-opcode-map.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt
index 12e3771..c4d5591 100644
--- a/arch/x86/lib/x86-opcode-map.txt
+++ b/arch/x86/lib/x86-opcode-map.txt
@@ -896,7 +896,7 @@ EndTable
GrpTable: Grp3_1
0: TEST Eb,Ib
-1:
+1: TEST Eb,Ib
2: NOT Eb
3: NEG Eb
4: MUL AL,Eb
next reply other threads:[~2017-11-24 7:44 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-24 7:39 tip-bot for Masami Hiramatsu [this message]
-- strict thread matches above, loose matches on Subject: below --
2017-11-24 7:22 [tip:x86/urgent] x86/decoder: Add new TEST instruction pattern tip-bot for Masami Hiramatsu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=tip-12a78d43de767eaf8fb272facb7a7b6f2dc6a9df@git.kernel.org \
--to=tipbot@zytor.com \
--cc=fengguang.wu@intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=stable@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.