From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753366AbXC0Ip2 (ORCPT ); Tue, 27 Mar 2007 04:45:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753378AbXC0Ip2 (ORCPT ); Tue, 27 Mar 2007 04:45:28 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:51985 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753366AbXC0Ip1 (ORCPT ); Tue, 27 Mar 2007 04:45:27 -0400 Date: Tue, 27 Mar 2007 01:45:24 -0700 From: Paul Jackson To: Srivatsa Vaddagiri Cc: balbir@in.ibm.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Fix race between attach_task and cpuset_exit Message-Id: <20070327014524.e4177467.pj@sgi.com> In-Reply-To: <20070327023559.y7gvoty7ksg4kw44@imap.linux.ibm.com> References: <20070325164746.GI11794@in.ibm.com> <4606B6CF.6040306@in.ibm.com> <20070326115046.GK11794@in.ibm.com> <20070326105813.5678ea5d.pj@sgi.com> <20070327023559.y7gvoty7ksg4kw44@imap.linux.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 > Yes, but the cpuset is not made invisible to userspace (in filesystem) > yet. So as cpuset_exit() discovers that cpuset B has zero refcount now > and blocks on mutex_lock(&manage_mutex) [ to do a check_for_release > later ], someone could have done a attach_task to that cpuset. Agreed. -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401