From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753106AbdK1MnK (ORCPT ); Tue, 28 Nov 2017 07:43:10 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:56846 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752260AbdK1KUU (ORCPT ); Tue, 28 Nov 2017 05:20:20 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, kbuild test robot , Masami Hiramatsu , "H. Peter Anvin" , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , Ingo Molnar Subject: [PATCH 3.18 05/67] x86/decoder: Add new TEST instruction pattern Date: Tue, 28 Nov 2017 11:19:04 +0100 Message-Id: <20171128100421.050048078@linuxfoundation.org> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171128100420.274075224@linuxfoundation.org> References: <20171128100420.274075224@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masami Hiramatsu commit 12a78d43de767eaf8fb272facb7a7b6f2dc6a9df upstream. The kbuild test robot reported this build warning: Warning: arch/x86/tools/test_get_len found difference at :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 Signed-off-by: Masami Hiramatsu Cc: Greg Kroah-Hartman Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/lib/x86-opcode-map.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/lib/x86-opcode-map.txt +++ b/arch/x86/lib/x86-opcode-map.txt @@ -814,7 +814,7 @@ EndTable GrpTable: Grp3_1 0: TEST Eb,Ib -1: +1: TEST Eb,Ib 2: NOT Eb 3: NEG Eb 4: MUL AL,Eb