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[209.132.180.67]) by mx.google.com with ESMTP id t15si9730034oij.189.2020.01.15.08.09.22; Wed, 15 Jan 2020 08:09:38 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@gmail.com header.s=20161025 header.b=djnWz5Uv; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729025AbgAOQHu (ORCPT + 99 others); Wed, 15 Jan 2020 11:07:50 -0500 Received: from mail-qt1-f195.google.com ([209.85.160.195]:38866 "EHLO mail-qt1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728949AbgAOQHt (ORCPT ); Wed, 15 Jan 2020 11:07:49 -0500 Received: by mail-qt1-f195.google.com with SMTP id c24so5413327qtp.5; Wed, 15 Jan 2020 08:07:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=zSIfSAzXaUnmeHj5yAo3f8W68OERKqDK+WA3I8DQXME=; b=djnWz5Uv5uxqmn8ZPz8gXmpXymRwdVRfn2Ka203Vjcor3GCoGHr4bsAzTivzjFgh6U qt/PLBVgXNj39rkovMYAxr5MF2wYd7D1+Yjilxz02n8uXjasXFbCy4q2YPMX0PGg9Q7v AFifPDmKFtqeQ5zKZkysF5IAlIlXIeTd/hR03AhLB7eM7sj1erDyBl6wQXZRkYGb04Qc bbJD7lp2zBvZqlWNllNjM1DJCYEHr14B0QQmorF72OTclYQWbKGU8GwceQF01uoCFeuJ PyGvhCAJEeDDu1VnZ2Dtc4Q53lNCP8LEMHDLfgq8EWFk/DBWB8cK2hTbyI/Ixct35Pyg iNxA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=zSIfSAzXaUnmeHj5yAo3f8W68OERKqDK+WA3I8DQXME=; b=iZexNFORkrGNHZSx8DbOh33CUdI2LntyDKfUrL9hF6PpI2L2ZlOo7XBDmbAnxhhGaw gpV0xL6uUWZBfBmVzUaYvq4huXBfubTmcN6M5U/KOemrMzCvpIqxOuBxmgJf/BerViPZ yLeUUYdMxniOOllQl/Je6dLi9d6OwJ/yewWHqEm3qz36cexI8MnDAX/8GkjCT2S2meN0 bomCX5/IZgYraY/Au5kgoeUhab7ihlIqkeuLsZ/Fjqp+8VVhyBQ71obn5OBMFg2b3UP6 IsfxsZXiGr5VP1FlbaWKkw+lebxmTj7PFl0tTd9OXpHq89/omDtMT6qKCyIgC1xxcqqm lsgw== X-Gm-Message-State: APjAAAVoMIs84YHDIyoPrIiu8P5+GKbmu2D08dPIjrpU8IYih9TV2KEB RkuNAAgl35RpyeF3zlOPMAouwsNYwao= X-Received: by 2002:ac8:3510:: with SMTP id y16mr4288551qtb.6.1579104468267; Wed, 15 Jan 2020 08:07:48 -0800 (PST) Received: from localhost ([2620:10d:c091:500::2:1e68]) by smtp.gmail.com with ESMTPSA id n4sm9344056qti.55.2020.01.15.08.07.47 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 15 Jan 2020 08:07:47 -0800 (PST) Date: Wed, 15 Jan 2020 08:07:46 -0800 From: Tejun Heo To: Michal =?iso-8859-1?Q?Koutn=FD?= Cc: cgroups@vger.kernel.org, Li Zefan , Johannes Weiner , linux-kernel@vger.kernel.org, Christian Brauner Subject: Re: [PATCH] cgroup: Prevent double killing of css when enabling threaded cgroup Message-ID: <20200115160746.GG2677547@devbig004.ftw2.facebook.com> References: <20191219022716.o7vxxia6o67tyfmf@wittgenstein> <20200109150559.14457-1-mkoutny@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200109150559.14457-1-mkoutny@suse.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 09, 2020 at 04:05:59PM +0100, Michal Koutn? wrote: > The commit prevents these situations by making cgroup_type_write wait > for all dying csses to go away before re-applying subtree controls. > When at it, the locations of WARN_ON_ONCE calls are moved so that > warning is triggered only when we are about to misuse the dying css. Applied to cgroup/for-5.6. Thanks. -- tejun