From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v2] cls_cgroup: Fix rcu lockdep warning Date: Fri, 03 Sep 2010 09:55:39 -0700 (PDT) Message-ID: <20100903.095539.220051635.davem@davemloft.net> References: <4C805293.1020305@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: herbert@gondor.hengli.com.au, davej@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, peterz@infradead.org, menage@google.com To: lizf@cn.fujitsu.com Return-path: In-Reply-To: <4C805293.1020305@cn.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Li Zefan Date: Fri, 03 Sep 2010 09:42:43 +0800 > Dave reported an rcu lockdep warning on 2.6.35.4 kernel > > task->cgroups and task->cgroups->subsys[i] are protected by RCU. > So we avoid accessing invalid pointers here. This might happen, > for example, when you are deref-ing those pointers while someone > move @task from one cgroup to another. > > Reported-by: Dave Jones > Signed-off-by: Li Zefan Applied, thanks.