From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992555AbXDDDHm (ORCPT ); Tue, 3 Apr 2007 23:07:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992557AbXDDDHm (ORCPT ); Tue, 3 Apr 2007 23:07:42 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.145]:33956 "EHLO e5.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992555AbXDDDHl (ORCPT ); Tue, 3 Apr 2007 23:07:41 -0400 Date: Wed, 4 Apr 2007 08:45:02 +0530 From: Srivatsa Vaddagiri To: Gautham R Shenoy Cc: Ingo Molnar , akpm@linux-foundation.org, paulmck@us.ibm.com, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, Oleg Nesterov , "Rafael J. Wysocki" , dipankar@in.ibm.com, dino@in.ibm.com, masami.hiramatsu.pt@hitachi.com Subject: Re: [RFC] Cpu-hotplug: Using the Process Freezer (try2) Message-ID: <20070404031502.GA23591@in.ibm.com> Reply-To: vatsa@in.ibm.com References: <20070402053457.GA9076@in.ibm.com> <20070402061612.GA7072@elte.hu> <20070402092818.GE2456@in.ibm.com> <20070402111828.GA14771@elte.hu> <20070402124200.GA9566@in.ibm.com> <20070402185607.GA2081@elte.hu> <20070403125619.GA32444@in.ibm.com> <20070403141516.GB14900@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070403141516.GB14900@in.ibm.com> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 03, 2007 at 07:45:16PM +0530, Gautham R Shenoy wrote: > > Should we ignore this for the timebeing and take up later as and when > > users report problems? > > In my case, the problem of freezer failing was due to the vfork freezer race > in do_fork. The parent task was waiting_for_completion() while the child was > frozen. Good catch and ... > Rafael has already sent out the fix for that, but for some reason I > don't see it in the -mm. > > With that fix, freezer and hence hotplug succeeds even when I am running > a 'make -j' test. Good to know that! So Ingo/Rafael, should we ignore the problem of "TASK_UNINTERRUPTIBLE sleepers can break freezer" for the timebeing? Mainly because its not trivial to solve and we need to tackle it case by case basis as and when users report specific problems. -- Regards, vatsa