From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Clayton Subject: Re: qemu-kvm-1.1.0 crashing with kernel 3.5.0-rc6 Date: Mon, 30 Jul 2012 15:07:17 +0100 Message-ID: <50169515.7050900@googlemail.com> References: <5011D123.4060101@googlemail.com> <5012719A.5080208@googlemail.com> <5012E659.7060304@googlemail.com> <50152FC8.20905@redhat.com> <50154294.9040705@googlemail.com> <50154632.7010304@redhat.com> <50155AF4.9050500@redhat.com> <5015662A.2000006@redhat.com> <501577D1.7030205@googlemail.com> <20120729175453.GA32360@redhat.com> <50158A97.3050909@googlemail.com> <50169389.1020607@googlemail.com> <50169421.6060406@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Gleb Natapov , Eric Northup , kvm@vger.kernel.org, Jan Kiszka To: Avi Kivity Return-path: Received: from mail-ee0-f46.google.com ([74.125.83.46]:36060 "EHLO mail-ee0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754393Ab2G3OHT (ORCPT ); Mon, 30 Jul 2012 10:07:19 -0400 Received: by eeil10 with SMTP id l10so1297115eei.19 for ; Mon, 30 Jul 2012 07:07:17 -0700 (PDT) In-Reply-To: <50169421.6060406@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 07/30/12 15:03, Avi Kivity wrote: > On 07/30/2012 05:00 PM, Chris Clayton wrote: >> On 07/29/12 20:10, Chris Clayton wrote: >>>>>> Possible culprit: b2da15ac26a0c00. >>>>>> >>>>>> >>>>> That commit isn't in qermu-kvm-1.1.1. >>>>> >>>> It is in kernel. >>>> >>> >>> Sorry, so it is. >>> >>> With kernel 3.5.0 with b2da15ac26a0c00 reverted, I have just had 15 >>> clean invocations of vanilla qemu-kvm-1.1.1. So that commit would seem >>> to be the problem. >> >> Just to be sure, I've run some more tests today. No crashes occurred in >> 20 runs of vanilla qemu-kvm-1.1.1 on kernel 3.5.0 with b2da15ac26a0c00 >> reverted. > > Ok. I'm trying to reproduce it here on a nested-virt setup, since the > code looks correct. > > What's your preemption settings? > > [chris:~/kernel/linux-3.5.0]$ grep PREEMPT .config CONFIG_TREE_PREEMPT_RCU=y CONFIG_PREEMPT_RCU=y CONFIG_PREEMPT_NOTIFIERS=y # CONFIG_PREEMPT_NONE is not set # CONFIG_PREEMPT_VOLUNTARY is not set CONFIG_PREEMPT=y CONFIG_PREEMPT_COUNT=y