Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756771Ab3G3SPd (ORCPT ); Tue, 30 Jul 2013 14:15:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:11589 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756582Ab3G3SPb (ORCPT ); Tue, 30 Jul 2013 14:15:31 -0400 Date: Tue, 30 Jul 2013 14:05:04 -0400 From: Dave Jones To: "Paul E. McKenney" Cc: Linux Kernel , linux-mm@kvack.org, kosaki.motohiro@gmail.com, walken@google.com, akpm@linux-foundation.org, torvalds@linux-foundation.org Subject: Re: mlockall triggred rcu_preempt stall. Message-ID: <20130730180504.GA4546@redhat.com> Mail-Followup-To: Dave Jones , "Paul E. McKenney" , Linux Kernel , linux-mm@kvack.org, kosaki.motohiro@gmail.com, walken@google.com, akpm@linux-foundation.org, torvalds@linux-foundation.org References: <20130719145323.GA1903@redhat.com> <20130719221538.GH21367@linux.vnet.ibm.com> <20130720003212.GA31308@redhat.com> <20130730175718.GA8957@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130730175718.GA8957@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1442 Lines: 34 On Tue, Jul 30, 2013 at 10:57:18AM -0700, Paul E. McKenney wrote: > On Fri, Jul 19, 2013 at 08:32:12PM -0400, Dave Jones wrote: > > On Fri, Jul 19, 2013 at 03:15:39PM -0700, Paul E. McKenney wrote: > > > On Fri, Jul 19, 2013 at 10:53:23AM -0400, Dave Jones wrote: > > > > My fuzz tester keeps hitting this. Every instance shows the non-irq stack > > > > came in from mlockall. I'm only seeing this on one box, but that has more > > > > ram (8gb) than my other machines, which might explain it. > > > > > > Are you building CONFIG_PREEMPT=n? I don't see any preemption points in > > > do_mlockall(), so a range containing enough vmas might well stall the > > > CPU in that case. > > > > That was with full preempt. > > > > > Does the patch below help? If so, we probably need others, but let's > > > first see if this one helps. ;-) > > > > I'll try it on Monday. > > Any news? If I don't hear otherwise, I will assume that the patch did > not help, and will therefore drop it. I wasn't able to do any tests yesterday, because I kept hitting other oopses. I've got patches for the more obvious ones now, so I'll start testing rc3 this afternoon. Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/