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=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 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 B9159C43331 for ; Tue, 31 Mar 2020 18:11:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8F5E0212CC for ; Tue, 31 Mar 2020 18:11:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727548AbgCaSLb (ORCPT ); Tue, 31 Mar 2020 14:11:31 -0400 Received: from mx2.suse.de ([195.135.220.15]:58604 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725988AbgCaSLb (ORCPT ); Tue, 31 Mar 2020 14:11:31 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id E9855AC52; Tue, 31 Mar 2020 18:11:26 +0000 (UTC) Message-ID: <1585678285.30493.27.camel@suse.cz> Subject: Re: [tip: sched/core] x86, sched: Add support for frequency invariance From: Giovanni Gherdovich To: Chris Wilson , linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org, tip-bot2 for Giovanni Gherdovich Cc: Peter Zijlstra , Ingo Molnar , Doug Smythies , "Rafael J. Wysocki" , x86 Date: Tue, 31 Mar 2020 20:11:25 +0200 In-Reply-To: <158556634294.3228.4889951961483021094@build.alporthouse.com> References: <20200122151617.531-2-ggherdovich@suse.cz> <158029757853.396.10568128383380430250.tip-bot2@tip-bot2> <158556634294.3228.4889951961483021094@build.alporthouse.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2020-03-30 at 12:05 +0100, Chris Wilson wrote: > Quoting tip-bot2 for Giovanni Gherdovich (2020-01-29 11:32:58) > > The following commit has been merged into the sched/core branch of tip: > > > > Commit-ID: 1567c3e3467cddeb019a7b53ec632f834b6a9239 > > Gitweb: https://git.kernel.org/tip/1567c3e3467cddeb019a7b53ec632f834b6a9239 > > Author: Giovanni Gherdovich > > AuthorDate: Wed, 22 Jan 2020 16:16:12 +01:00 > > Committer: Ingo Molnar > > CommitterDate: Tue, 28 Jan 2020 21:36:59 +01:00 > > [...] > > Since this has become visible via linux-next [20200326?], we have been > deluged by oops during cpu-hotplug. > > <6> [184.949219] [IGT] perf_pmu: starting subtest cpu-hotplug > <4> [185.092279] IRQ 24: no longer affine to CPU0 > <4> [185.092285] IRQ 25: no longer affine to CPU0 > <6> [185.093709] smpboot: CPU 0 is now offline > <6> [186.107062] smpboot: Booting Node 0 Processor 0 APIC 0x0 > <3> [186.107643] BUG: sleeping function called from invalid context at ./include/linux/percpu-rwsem.h:49 > <3> [186.107648] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/0 > [...] > > repeating ad nauseam, e.g. > https://intel-gfx-ci.01.org/tree/linux-next/next-20200327/shard-hsw4/dmesg9.txt > > Across all our test boxen. > -Chris Hello Chris, thank you for catching this problem and sorry for the mess. Until your message I wasn't aware that CPU0 can be hotplugged, but now that I check the feature is been there since v3.8 :/ The code assumes cpu0 is always there and I need to fix that. It seems your report comes from executing an automated test suite, can you give me a link to the test sources and a hint on how to run it? I'd like to reproduce locally so that I make sure I correctly address this problem. Thanks, Giovanni