From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755978Ab1BQBtm (ORCPT ); Wed, 16 Feb 2011 20:49:42 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:62704 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751520Ab1BQBtk (ORCPT ); Wed, 16 Feb 2011 20:49:40 -0500 Message-ID: <4D5C7F00.2050802@cn.fujitsu.com> Date: Thu, 17 Feb 2011 09:50:56 +0800 From: Li Zefan User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.9) Gecko/20100921 Fedora/3.1.4-1.fc14 Thunderbird/3.1.4 MIME-Version: 1.0 To: Andrew Morton CC: LKML , Paul Menage , David Rientjes , =?UTF-8?B?57yqIOWLsA==?= , linux-mm@kvack.org Subject: [PATCH 4/4] cpuset: Hold callback_mutex in cpuset_clone() References: <4D5C7EA7.1030409@cn.fujitsu.com> In-Reply-To: <4D5C7EA7.1030409@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-02-17 09:48:40, Serialize by Router on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-02-17 09:48:41, Serialize complete at 2011-02-17 09:48:41 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Chaning cpuset->mems/cpuset->cpus should be protected under callback_mutex. cpuset_clone() doesn't follow this rule. It's ok because it's called when creating and initializing a cgroup, but we'd better hold the lock to avoid subtil break in the future. Signed-off-by: Li Zefan --- kernel/cpuset.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 1e18d26..445573b 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1840,8 +1840,10 @@ static void cpuset_post_clone(struct cgroup_subsys *ss, cs = cgroup_cs(cgroup); parent_cs = cgroup_cs(parent); + mutex_lock(&callback_mutex); cs->mems_allowed = parent_cs->mems_allowed; cpumask_copy(cs->cpus_allowed, parent_cs->cpus_allowed); + mutex_unlock(&callback_mutex); return; } -- 1.7.3.1