From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754828AbZLTNgp (ORCPT ); Sun, 20 Dec 2009 08:36:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754109AbZLTNgo (ORCPT ); Sun, 20 Dec 2009 08:36:44 -0500 Received: from mx01.qsc.de ([213.148.129.14]:51606 "EHLO mx01.qsc.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753854AbZLTNgn (ORCPT ); Sun, 20 Dec 2009 08:36:43 -0500 X-Greylist: delayed 540 seconds by postgrey-1.27 at vger.kernel.org; Sun, 20 Dec 2009 08:36:43 EST Message-ID: <4B2E264E.4090805@googlemail.com> Date: Sun, 20 Dec 2009 14:27:42 +0100 From: =?ISO-8859-1?Q?Holger_Hoffst=E4tte?= User-Agent: Thunderbird 2.0.0.23 (Windows/20090812) MIME-Version: 1.0 To: Willy Tarreau CC: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Mike Galbraith Subject: Re: [stable] Regression in 2.6.32.2: segfault on halt References: <20091220054847.GF32739@1wt.eu> <4B2E10C6.7050304@googlemail.com> <20091220130616.GC9719@1wt.eu> In-Reply-To: <20091220130616.GC9719@1wt.eu> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Willy Tarreau wrote: > Hi Holger, > > On Sun, Dec 20, 2009 at 12:55:50PM +0100, Holger Hoffstätte wrote: >> Willy Tarreau wrote: >>> On Sat, Dec 19, 2009 at 04:10:49PM +0100, Holger Hoffstaette wrote: >>>> After updating to 2.6.32.2 last night (using same config from .32.1) I >>>> noticed that "halt" now trips during shutdown and won't power the >>>> machine down any longer. This happens reproducibly on two completely >>>> different machines, so it looks like a generic problem and regression, >>>> since it did not happen in .32.1. Note that "reboot" works as expected - >>>> only "halt" crashes. >>> I have it working fine here. So your config helps to reproduce the issue. >>> Care to post it ? >> Attached, if it matters. However I managed to find some time with a spare >> machine and always wanted to try bisect, so that's what I did - apparently >> successfully: >> >> root>git bisect bad >> 37ed2d7007a65874850f3e357c095806c3756330 is the first bad commit >> commit 37ed2d7007a65874850f3e357c095806c3756330 >> Author: Mike Galbraith >> Date: Wed Nov 4 17:53:50 2009 +0100 >> >> sched: Rate-limit newidle > > Interesting, because I saw this one too while digging the patch preview > for the word "migration" which appeared in your trace. But these changes > did not look suspicious (no obvious invalid pointer dereference for > instance). > > CCing Mike who may have an idea. Took me some time (still learning git - I usually use hg) but I just managed to fix it by reverting not the bisected revision (won't compile any longer), but the follow-up "cleanup & fix": >>From 35c1ee3e78766d5666f418af638def9c67e63ecb Mon Sep 17 00:00:00 2001 From: Mike Galbraith Date: Tue, 10 Nov 2009 03:50:02 +0100 Subject: [PATCH] sched: Fix and clean up rate-limit newidle code commit eae0c9dfb534cb3449888b9601228efa6480fdb5 upstream. Commit 1b9508f, "Rate-limit newidle" has been confirmed to fix the netperf UDP loopback regression reported by Alex Shi. This is a cleanup and a fix: - moved to a more out of the way spot - fix to ensure that balancing doesn't try to balance runqueues which haven't gone online yet, which can mess up CPU enumeration during boot. Reported-by: Alex Shi Reported-by: Zhang, Yanmin Signed-off-by: Mike Galbraith Acked-by: Peter Zijlstra LKML-Reference: <1257821402.5648.17.camel@marge.simson.net> Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman aka: http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.32.y.git;a=commit;h=35c1ee3e78766d5666f418af638def9c67e63ecb Reverting this from a clean 32.2 tree results in a kernel with newidle fix, but still working halt/reboot. The only difference between this and the bisected one is the additional change in cpumask handling. That was more fun than expected :) Holger