Received: by 2002:a05:6a10:7420:0:0:0:0 with SMTP id hk32csp464528pxb; Thu, 17 Feb 2022 07:49:24 -0800 (PST) X-Google-Smtp-Source: ABdhPJwiGLqEld0szqOhEDwR2QnFgnL/okvLpoDh5DSVolEj9e/K9GQr9140AhNJPhFEadKPOe+0 X-Received: by 2002:a17:906:7245:b0:6cf:d3c6:8c63 with SMTP id n5-20020a170906724500b006cfd3c68c63mr2671817ejk.677.1645112964304; Thu, 17 Feb 2022 07:49:24 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1645112964; cv=none; d=google.com; s=arc-20160816; b=0XPVODHdljicmyfsoj4dP9bKWGOlCmCEQBNgpzDWOavjWz8HGYlm0MMyxKca0QHnQQ lbrWm9KaIC0HX+9N8k2Y7hBSEr6qbukCZgeblC0/dTcqF+I5HXbeivPE3SeMOtz7CQ3Z 9BSLtIU7B8M/MnXTtqD6rz07S8s1MuV7YWe/sEAd4PHpv2OUGeqsvtlqBLZ5N8QOvZLa ttqcdIxVJBMjdYwPjV85vsZb/TU5zX+lqTj0drKojpsZvZAf0L2qlUR05sfNin9C+rX8 N2tLTLLRT43fyuHXLtqI1fyUJVuQBj8LMBcR+8N1gb1jvQ/C/8nGwub9RuhgcNno7qCv LMhA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:content-language :in-reply-to:mime-version:user-agent:date:message-id:from:references :cc:to:subject; bh=+ZNzlzpl8fB2KgF02G0sxSQzA8Pu6KoJfuQbA7IFBBc=; b=KpEs+zivr0dI6GUQJl0YRaCpSGKX+As696GrWpNNdqElIyAy4ShWDrLthLj140O3NC CRtWHgvI+L/4OXIqZ8kPa+esHuAvgFnJeeaUufcDu7gfeGU1iMC0HRP9POo6EbrAjasM /fa39gMmC8+NaTTdoZXb3EQzvPTMn6ohrhkc+YrwSzUmPypl2993cQEe5+fBI8p+q1rC 6N4CEpaG7e66Cz+2BAGBUswWgWGtvhjwVF74Z9mjaQ/ssg9rBk9ptvLTmw6y5DnlIrPP 0Cpwpe+B9pIXtdpLOYY7CMs54NsaKjrMCv2z6wM5EpInd4loSq8Ifi1+eCVp5/7SwZm+ 6zEw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id hr4si2545460ejc.321.2022.02.17.07.48.59; Thu, 17 Feb 2022 07:49:24 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239346AbiBQKvB (ORCPT + 99 others); Thu, 17 Feb 2022 05:51:01 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:42936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237741AbiBQKu6 (ORCPT ); Thu, 17 Feb 2022 05:50:58 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 346081ED1E7 for ; Thu, 17 Feb 2022 02:50:44 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id F36F0D6E; Thu, 17 Feb 2022 02:50:43 -0800 (PST) Received: from [192.168.178.6] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id AF8093F66F; Thu, 17 Feb 2022 02:50:42 -0800 (PST) Subject: Re: [PATCH] sched: Fix yet more sched_fork() races To: Peter Zijlstra , Linus Torvalds Cc: Borislav Petkov , Tadeusz Struk , x86-ml , lkml , zhangqiao22@huawei.com, tj@kernel.org References: From: Dietmar Eggemann Message-ID: Date: Thu, 17 Feb 2022 11:50:31 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00,NICE_REPLY_A, RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17/02/2022 09:51, Peter Zijlstra wrote: > On Mon, Feb 14, 2022 at 10:16:57AM +0100, Peter Zijlstra wrote: >> Zhang, Tadeusz, TJ, how does this look? > > *sigh* I was hoping for some Tested-by, since I've no idea how to > operate this cgroup stuff properly. At least the reproducer from https://syzkaller.appspot.com/bug?id=9d9c27adc674e3a7932b22b61c79a02da82cbdc1 doesn't barf with this patch but it does on 5.17-rc2 on Arm64 Juno-r0. sched: Fix yet more sched_fork() races (2022-02-17 Peter Zijlstra) 13765de8148f - sched/fair: Fix fault in reweight_entity (2022-02-06 Tadeusz Struk) 26291c54e111 - Linux 5.17-rc2 (2022-01-30 Linus Torvalds) Tested-by: Dietmar Eggemann [...]