From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752564AbdI1Itr (ORCPT ); Thu, 28 Sep 2017 04:49:47 -0400 Received: from mail-wr0-f196.google.com ([209.85.128.196]:38419 "EHLO mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751917AbdI1Itp (ORCPT ); Thu, 28 Sep 2017 04:49:45 -0400 X-Google-Smtp-Source: AOwi7QDfZT56ALvqe5dY//oxelnjcztlIbswoki4HRb4FzJxCjvwBlLTW0hmngxV3ny4BjxT9bRU1A== Date: Thu, 28 Sep 2017 10:49:41 +0200 From: Ingo Molnar To: Peter Zijlstra Cc: kernel test robot , Josh Poimboeuf , Andrey Ryabinin , Matthias Kaehlcke , Alexander Potapenko , Andy Lutomirski , Arnd Bergmann , Dmitriy Vyukov , Linus Torvalds , Miguel Bernal Marin , Thomas Gleixner , LKML , lkp@01.org Subject: Re: [lkp-robot] [x86/asm] f5caf621ee: PANIC:double_fault Message-ID: <20170928084941.ygmvb6qfn3otfvac@gmail.com> References: <20170928074758.GS17200@yexl-desktop> <20170928075907.bpxlop6bq4bn54sk@gmail.com> <20170928081850.ep3nqulhxeakwmzs@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170928081850.ep3nqulhxeakwmzs@hirez.programming.kicks-ass.net> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Peter Zijlstra wrote: > On Thu, Sep 28, 2017 at 09:59:07AM +0200, Ingo Molnar wrote: > > > > * kernel test robot wrote: > > > > > > > > FYI, we noticed the following commit: > > > > > > commit: f5caf621ee357279e759c0911daf6d55c7d36f03 ("x86/asm: Fix inline asm call constraints for Clang") > > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > > > > > in testcase: trinity > > > with following parameters: > > > > > > runtime: 300s > > > > > > test-description: Trinity is a linux system call fuzz tester. > > > test-url: http://codemonkey.org.uk/projects/trinity/ > > > > > > > > > on test machine: qemu-system-x86_64 -enable-kvm -m 420M > > > > > > caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): > > > > > > > > > +-----------------------------------------+------------+------------+ > > > | | 0d0970eef3 | f5caf621ee | > > > +-----------------------------------------+------------+------------+ > > > | boot_successes | 9 | 4 | > > > | boot_failures | 0 | 4 | > > > | PANIC:double_fault | 0 | 4 | > > > | Kernel_panic-not_syncing:Machine_halted | 0 | 4 | > > > +-----------------------------------------+------------+------------+ > > > > I think a key piece of information is that the test is using GCC 4.4: > > > > export compiler='gcc-4.4' > > > > ... which is pretty old compared to what gets tested typically. > > > > GCC 4.4 was released in 2009 (!), the last minor update of 4.4.7 was 5 years ago. > > Sure, but its still an officially supported GCC version. So either it > must be made to work, or we must update the minimal GCC version > requirements for the kernel. Of course! I just mean I'd not be surprised if this was a GCC bug/quirk with legacy GCC versions that probably won't be fixed. Thanks, Ingo From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============3131357111999782368==" MIME-Version: 1.0 From: Ingo Molnar To: lkp@lists.01.org Subject: Re: [lkp-robot] [x86/asm] f5caf621ee: PANIC:double_fault Date: Thu, 28 Sep 2017 10:49:41 +0200 Message-ID: <20170928084941.ygmvb6qfn3otfvac@gmail.com> In-Reply-To: <20170928081850.ep3nqulhxeakwmzs@hirez.programming.kicks-ass.net> List-Id: --===============3131357111999782368== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable * Peter Zijlstra wrote: > On Thu, Sep 28, 2017 at 09:59:07AM +0200, Ingo Molnar wrote: > > = > > * kernel test robot wrote: > > = > > > = > > > FYI, we noticed the following commit: > > > = > > > commit: f5caf621ee357279e759c0911daf6d55c7d36f03 ("x86/asm: Fix inlin= e asm call constraints for Clang") > > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > > = > > > in testcase: trinity > > > with following parameters: > > > = > > > runtime: 300s > > > = > > > test-description: Trinity is a linux system call fuzz tester. > > > test-url: http://codemonkey.org.uk/projects/trinity/ > > > = > > > = > > > on test machine: qemu-system-x86_64 -enable-kvm -m 420M > > > = > > > caused below changes (please refer to attached dmesg/kmsg for entire = log/backtrace): > > > = > > > = > > > +-----------------------------------------+------------+------------+ > > > | | 0d0970eef3 | f5caf621ee | > > > +-----------------------------------------+------------+------------+ > > > | boot_successes | 9 | 4 | > > > | boot_failures | 0 | 4 | > > > | PANIC:double_fault | 0 | 4 | > > > | Kernel_panic-not_syncing:Machine_halted | 0 | 4 | > > > +-----------------------------------------+------------+------------+ > > = > > I think a key piece of information is that the test is using GCC 4.4: > > = > > export compiler=3D'gcc-4.4' > > = > > ... which is pretty old compared to what gets tested typically. > > = > > GCC 4.4 was released in 2009 (!), the last minor update of 4.4.7 was 5 = years ago. > = > Sure, but its still an officially supported GCC version. So either it > must be made to work, or we must update the minimal GCC version > requirements for the kernel. Of course! I just mean I'd not be surprised if this was a GCC bug/quirk with legacy GCC versions that probably won't be fixed. Thanks, Ingo --===============3131357111999782368==--