Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758449Ab1E0IAy (ORCPT ); Fri, 27 May 2011 04:00:54 -0400 Received: from service87.mimecast.com ([94.185.240.25]:43797 "HELO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751274Ab1E0IAx convert rfc822-to-8bit (ORCPT ); Fri, 27 May 2011 04:00:53 -0400 Subject: Re: [BUG] "sched: Remove rq->lock from the first half of ttwu()" locks up on ARM From: Marc Zyngier To: Peter Zijlstra Cc: Oleg Nesterov , Yong Zhang , Ingo Molnar , Frank Rowand , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org In-Reply-To: <1306427537.2497.86.camel@laptop> References: <1306260792.27474.133.camel@e102391-lin.cambridge.arm.com> <1306272750.2497.79.camel@laptop> <1306343335.21578.65.camel@twins> <1306358128.21578.107.camel@twins> <1306405979.1200.63.camel@twins> <1306407759.27474.207.camel@e102391-lin.cambridge.arm.com> <1306409575.1200.71.camel@twins> <1306412511.1200.90.camel@twins> <20110526154508.GA13788@redhat.com> <1306425584.2497.81.camel@laptop> <1306426148.2497.83.camel@laptop> <1306426823.27474.241.camel@e102391-lin.cambridge.arm.com> <1306427537.2497.86.camel@laptop> Organization: ARM Ltd Date: Fri, 27 May 2011 09:01:35 +0100 Message-ID: <1306483295.27474.248.camel@e102391-lin.cambridge.arm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 X-OriginalArrivalTime: 27 May 2011 08:01:01.0953 (UTC) FILETIME=[3894C710:01CC1C44] X-MC-Unique: 111052709004904101 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1084 Lines: 31 On Thu, 2011-05-26 at 18:32 +0200, Peter Zijlstra wrote: > On Thu, 2011-05-26 at 17:20 +0100, Marc Zyngier wrote: > > > > Doesn't look very good here. The serial console basically locks up as > > soon as the system gets busy, even if the kernel compilation seem to > > progress at a decent pace. > > > OK, I'll leave the one that worked queued up for this release. If we can > come up with a better alternative we can try for the next release, that > should give us ample time to test things and get us a working kernel > now ;-) Agreed. The board has been compiling kernels for over 15 hours now, and doesn't show any sign of deadlock. Yet ;-). So until someone comes up with a much better approach, let's keep this one. I'm of course happy to continue testing stuff though. Cheers, M. -- Reality is an implementation detail. -- 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/