From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8B56C433DB for ; Tue, 9 Mar 2021 10:05:58 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4C30065257 for ; Tue, 9 Mar 2021 10:05:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4C30065257 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.95290.179811 (Exim 4.92) (envelope-from ) id 1lJZF0-0007C2-Ec; Tue, 09 Mar 2021 10:05:26 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 95290.179811; Tue, 09 Mar 2021 10:05:26 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lJZF0-0007Bv-As; Tue, 09 Mar 2021 10:05:26 +0000 Received: by outflank-mailman (input) for mailman id 95290; Tue, 09 Mar 2021 10:05:24 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lJZEy-0007Bq-H7 for xen-devel@lists.xenproject.org; Tue, 09 Mar 2021 10:05:24 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lJZEv-0004WG-0j; Tue, 09 Mar 2021 10:05:21 +0000 Received: from 54-240-197-231.amazon.com ([54.240.197.231] helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1lJZEu-0007DG-HT; Tue, 09 Mar 2021 10:05:20 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject; bh=Ydd65JX7traKb0hGUfqh3WQxjaeJ9AE7hlTdwXR+3jY=; b=P3Ni8lt34Fv3Ms+AHOJIzgIPQD dEY+V96J0fXpV3jdfQZBmX/QDCZ0PM3i22Y0mUzHOz+1QYKUvQL5M0IW/7+4fsPmW+viiTest5ypE 4mJ8cpHNIWYMUdhUANIIkkCWBLt3C/QgxfiKIO6ZxZT3wlOW2hiQTu0UGX8H8me1pCGc=; Subject: Re: [PATCH for-4.15] xen: Bump the minimum version of GCC supported to 4.9 (5.1 on arm64) To: Stefano Stabellini Cc: xen-devel@lists.xenproject.org, famzheng@amazon.com, cardoe@cardoe.com, wl@xen.org, Bertrand.Marquis@arm.com, andrew.cooper3@citrix.com References: <161507188317.11025.6744028462008264481@c667a6b167f6> From: Julien Grall Message-ID: <10b8048a-e8fe-1fcd-7291-7f1b16da2f4c@xen.org> Date: Tue, 9 Mar 2021 10:05:18 +0000 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Hi Stefano, On 09/03/2021 00:59, Stefano Stabellini wrote: > On Sun, 7 Mar 2021, Julien Grall wrote: >> On 06/03/2021 23:04, no-reply@patchew.org wrote: >>> Hi, >>> >>> Patchew automatically ran gitlab-ci pipeline with this patch (series) >>> applied, but the job failed. Maybe there's a bug in the patches? >>> >>> You can find the link to the pipeline near the end of the report below: >>> >>> Type: series >>> Message-id: 20210306214148.27021-1-julien@xen.org >>> Subject: [PATCH for-4.15] xen: Bump the minimum version of GCC supported to >>> 4.9 (5.1 on arm64) >>> >>> === TEST SCRIPT BEGIN === >>> #!/bin/bash >>> sleep 10 >>> patchew gitlab-pipeline-check -p xen-project/patchew/xen >>> === TEST SCRIPT END === >>> >>> warning: redirecting to https://gitlab.com/xen-project/patchew/xen.git/ >>> warning: redirecting to https://gitlab.com/xen-project/patchew/xen.git/ >>> From https://gitlab.com/xen-project/patchew/xen >>> * [new tag] patchew/20210306214148.27021-1-julien@xen.org -> >>> patchew/20210306214148.27021-1-julien@xen.org >>> Switched to a new branch 'test' >>> f332859b88 xen: Bump the minimum version of GCC supported to 4.9 (5.1 on >>> arm64) >>> >>> === OUTPUT BEGIN === >>> [2021-03-06 21:45:17] Looking up pipeline... >>> [2021-03-06 21:45:18] Found pipeline 266507477: >>> >>> https://gitlab.com/xen-project/patchew/xen/-/pipelines/266507477 >>> >>> [2021-03-06 21:45:18] Waiting for pipeline to finish... >>> [2021-03-06 22:00:21] Still waiting... >>> [2021-03-06 22:15:26] Still waiting... >>> [2021-03-06 22:30:31] Still waiting... >>> [2021-03-06 22:45:35] Still waiting... >>> [2021-03-06 23:00:41] Still waiting... >>> [2021-03-06 23:04:42] Pipeline failed >>> [2021-03-06 23:04:42] Job 'qemu-smoke-x86-64-clang-pvh' in stage 'test' is >>> skipped >>> [2021-03-06 23:04:42] Job 'qemu-smoke-x86-64-gcc-pvh' in stage 'test' is >>> skipped >>> [2021-03-06 23:04:42] Job 'qemu-smoke-x86-64-clang' in stage 'test' is >>> skipped >>> [2021-03-06 23:04:42] Job 'qemu-smoke-x86-64-gcc' in stage 'test' is skipped >>> [2021-03-06 23:04:42] Job 'qemu-smoke-arm64-gcc' in stage 'test' is skipped >>> [2021-03-06 23:04:42] Job 'qemu-alpine-arm64-gcc' in stage 'test' is skipped >>> [2021-03-06 23:04:42] Job 'build-each-commit-gcc' in stage 'test' is skipped >>> [2021-03-06 23:04:42] Job 'alpine-3.12-clang' in stage 'build' is failed >> >> The following jobs are failing: >> >> alpine-3.12-clang [1] >> debian-unstable-32-gcc-debug >> debian-unstable-clang >> debian-unstable-gcc-randconfig >> ubuntu-bionic-clang >> >> Cloning into 'qemu-xen-dir-remote.tmp'... >> error: inflate: data stream error (incorrect data check) >> fatal: serious inflate inconsistency >> fatal: index-pack failed >> >> This looks unrelated to my patch. Possibly a network error? > > Yeah. > > >> ========= >> >> centos-7-2-gcc [2] >> centos-7-2-gcc-debug >> centos-7-gcc >> centos-7-gcc-debug >> >> Centos 7 is using GCC 4.8.5. This patch is bumping the minimum version to 4.9. >> So the failure is expected. >> >> We may have to disable the jobs if my patch goes ahead. May I ask why we chose >> to build on Centos 7? > > CentOS 7 is still the latest and it is maintained until 2024: > > https://wiki.centos.org/About/Product > > I don't have a lot of direct experience with x86 users any longer, but > this seems to be problematic? The last full updates was on the Q3 2020, so it looks unlikely that Centos 7 will upgrade to a new Xen. So this is only going to be a problem for anyone that decides to build there own Xen. I can't tell whether someone may want to build upstream Xen on Centos 7. What I can say is the Arm64 bug in GCC 4.9 will lead to corruption, the bug in GCC < 4.8 looks somewhat less problematic. So, I am sure any user would appreciate if we tell (e.g. throw an error) them when there is a risk that GCC X.Y may miscompile Xen. In the ideal world (e.g if we had unlimited time), we should workaround it in Xen. But this doesn't look easy/possible here. Therefore, for now, I think dropping support for GCC < 4.9 (< 5.1 for Arm) is the best approach. The support can be revived when someone is willing to spend time on it. > > >> ========== >> >> ubuntu-trusty-gcc [3] >> ubuntu-trusty-gcc-debug >> >> Ubuntu trusty is using GCC 4.8.4. This patch is bumping the minimum version to >> 4.9. So the failure is expected. We may have to disable the jobs if my patch >> goes ahead. May I ask why we chose to build on Ubuntu trusty? > > Ubuntu Trusty is in "Extended Security Maintenance", so technically > still supported also: > > https://ubuntu.com/about/release-cycle See above. Cheers, -- Julien Grall