From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758329Ab3LFSCg (ORCPT ); Fri, 6 Dec 2013 13:02:36 -0500 Received: from relay.parallels.com ([195.214.232.42]:32883 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754056Ab3LFSCf (ORCPT ); Fri, 6 Dec 2013 13:02:35 -0500 Message-ID: <52A21136.9090605@parallels.com> Date: Fri, 6 Dec 2013 22:02:30 +0400 From: Vladimir Davydov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130922 Icedove/17.0.9 MIME-Version: 1.0 To: Tejun Heo CC: Li Zefan , , , Subject: Re: [PATCH cgroup/for-3.13-fixes] cgroup: fix oops in cgroup init failure path References: <1386234006-1633-1-git-send-email-vdavydov@parallels.com> <20131205211814.GA29598@mtj.dyndns.org> <52A1766F.5090808@parallels.com> <20131206161312.GC13373@htj.dyndns.org> In-Reply-To: <20131206161312.GC13373@htj.dyndns.org> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [81.5.110.170] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/06/2013 08:13 PM, Tejun Heo wrote: > Hello, Vladimir. > > On Fri, Dec 06, 2013 at 11:02:07AM +0400, Vladimir Davydov wrote: >> This patch fixes this bug, but I have a couple of questions regarding it. >> >> First, cgroup_load_subsys() also calls css_online(), and if it fails, it >> calls cgroup_unload_subsys() to rollback. The latter function executes >> the following command: >> >> offline_css(cgroup_css(cgroup_dummy_top, ss)); >> >> But since we failed to online_css(), cgroup_css() will return NULL >> resulting in another oops. > I don't think the root css onlining fails for any existing controllers > but yeah that looks wrong. Can you please send a patch? Sure, I will send it soon. Thanks.