From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751277AbeBJQBy (ORCPT ); Sat, 10 Feb 2018 11:01:54 -0500 Received: from mail.kernel.org ([198.145.29.99]:47180 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751052AbeBJQBx (ORCPT ); Sat, 10 Feb 2018 11:01:53 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E09A02173B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=mhiramat@kernel.org Date: Sun, 11 Feb 2018 01:01:48 +0900 From: Masami Hiramatsu To: "Hao, Shun" Cc: "Wu, Fengguang" , Ingo Molnar , "kbuild-all@01.org" , "linux-kernel@vger.kernel.org" Subject: Re: [kbuild-all] arch/x86/tools/insn_decoder_test: warning: ffffffff810005ac: 0f ff e9 ud0 %ecx, %ebp Message-Id: <20180211010148.ac3f6d7a7a73828eb2309076@kernel.org> In-Reply-To: References: <201802080625.McxPAKsk%fengguang.wu@intel.com> <20180208233421.ae91bc45d5c264eb85c52e05@kernel.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Fri, 9 Feb 2018 00:30:20 +0000 "Hao, Shun" wrote: > Thanks Masami, so that explains why a lot of these warnings come out just after > we upgrading to gcc-7.3 (now the objdump version is 2.30). > Currently we've already ignore these warnings and won't send this report. Anyway, it must be fixed with the below patch. https://lkml.org/lkml/2018/2/8/350 (Sorry, I replyed to another warning mail) Thank you, > > >-----Original Message----- > >From: kbuild-all [mailto:kbuild-all-bounces@lists.01.org] On Behalf Of Masami > >Hiramatsu > >Sent: Thursday, February 8, 2018 10:34 PM > >To: Wu, Fengguang > >Cc: Ingo Molnar ; kbuild-all@01.org; linux- > >kernel@vger.kernel.org > >Subject: Re: [kbuild-all] arch/x86/tools/insn_decoder_test: warning: ffffffff810005ac: > >0f ff e9 ud0 %ecx, %ebp > > > >On Thu, 8 Feb 2018 06:04:45 +0800 > >kbuild test robot wrote: > > > >> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > >> head: 7590e37bdaeec25ae325f4ba450be13e2aac6c8d > >> commit: 10c91577d5e631773a6394e14cf60125389b71ae x86/tools: Standardize > >output format of insn_decode_test > >> date: 8 weeks ago > >> config: x86_64-randconfig-s2-02072130 (attached as .config) > >> compiler: gcc-6 (Debian 6.4.0-9) 6.4.0 20171026 > >> reproduce: > >> git checkout 10c91577d5e631773a6394e14cf60125389b71ae > >> # save the attached .config to linux build tree > >> make ARCH=x86_64 > >> > >> All warnings (new ones prefixed by >>): > >> > >> arch/x86/tools/insn_decoder_test: warning: Found an x86 instruction decoder bug, > >please report this. > >> >> arch/x86/tools/insn_decoder_test: warning: ffffffff810005ac: 0f ff e9 > > ud0 %ecx,%ebp > > > >Does UD0 really take an operand? Hmm, indeed, the latest Intel SDM (December2017) > >says > > > >NOTES: > >1. Some older processors decode the UD0 instruction without a ModR/M byte. As a > >result, those processors would deliver an invalid- > >opcode exception instead of a fault on instruction fetch when the instruction with a > >ModR/M byte (and any implied bytes) would > >cross a page or segment boundary. > > > >and older SDM (e.g. March 2017) says UD0 has no modrm byte. > >It is easy to change x86-opecode-map.txt, but this means this test may fail with older > >objdump... > > > >> > >> --- > >> 0-DAY kernel test infrastructure Open Source Technology Center > >> https://lists.01.org/pipermail/kbuild-all Intel Corporation > > > > > >-- > >Masami Hiramatsu > >_______________________________________________ > >kbuild-all mailing list > >kbuild-all@lists.01.org > >https://lists.01.org/mailman/listinfo/kbuild-all -- Masami Hiramatsu