From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933001AbXCYBld (ORCPT ); Sat, 24 Mar 2007 21:41:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753324AbXCYBld (ORCPT ); Sat, 24 Mar 2007 21:41:33 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:47024 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753323AbXCYBlc (ORCPT ); Sat, 24 Mar 2007 21:41:32 -0400 Date: Sat, 24 Mar 2007 18:41:28 -0700 From: Paul Jackson To: vatsa@in.ibm.com Cc: sekharan@us.ibm.com, ckrm-tech@lists.sourceforge.net, linux-kernel@vger.kernel.org, xemul@sw.ru, dev@sw.ru, rohitseth@google.com, ebiederm@xmission.com, mbligh@google.com, winget@google.com, containers@lists.osdl.org, serue@us.ibm.com, menage@google.com, devel@openvz.org Subject: Re: [ckrm-tech] [PATCH 1/7] containers (V7): Generic container system abstracted from cpusets code Message-Id: <20070324184128.e8b34a3e.pj@sgi.com> In-Reply-To: <20070325004529.GD11794@in.ibm.com> References: <20070212081521.808338000@menage.corp.google.com> <20070212085104.130746000@menage.corp.google.com> <20070324150505.GB9475@in.ibm.com> <20070324122559.11b9ba34.pj@sgi.com> <20070325004529.GD11794@in.ibm.com> Organization: SGI X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.3; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org vatsa wrote: > > if (tsk->flags & PF_EXITING) { > > What if PF_EXITING is set after this check? If that happens then, > > > task_unlock(tsk); > > mutex_unlock(&callback_mutex); > > put_task_struct(tsk); > > return -ESRCH; > > } > > the following code becomes racy with cpuset_exit() ... > > atomic_inc(&cs->count); > rcu_assign_pointer(tsk->cpuset, cs); > task_unlock(tsk); eh ... so ... ? I don't know of any sequence where that causes any problem. Do you see one? -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401