From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [Qemu-devel] E5-2620v2 - emulation stop error Date: Wed, 01 Apr 2015 15:19:32 +0200 Message-ID: <551BF064.9030506@redhat.com> References: <20150330185634.GE13271@potion.brq.redhat.com> <20150331134512.GG13271@potion.brq.redhat.com> <20150331164539.GD14262@potion.brq.redhat.com> <20150401114923.GH13271@potion.brq.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Bandan Das , "Kevin O'Connor" , "Dr. David Alan Gilbert" , Gerd Hoffmann , "qemu-devel@nongnu.org" , "kvm@vger.kernel.org" To: Andrey Korolyov , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= Return-path: Received: from mx1.redhat.com ([209.132.183.28]:39992 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753558AbbDANTm (ORCPT ); Wed, 1 Apr 2015 09:19:42 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 01/04/2015 14:26, Andrey Korolyov wrote: > Yes, I disabled host watchdog during runtime. Indeed guest-induced NMI > would look different and they had no reasons to be fired at this stage > inside guest. I`d suspect a hypervisor hardware misbehavior there but > have a very little idea on how APICv behavior (which is completely > microcode-dependent and CPU-dependent but decoupled from peripheral > hardware) may vary at this point, I am using 1.20140913.1 ucode > version from debian if this can matter. Will send trace suggested by > Paolo in a next couple of hours. Also it would be awesome to ask > hardware folks from Intel who can prove or disprove my abovementioned > statement (as I was unable to catch the problem on 2603v2 so far, this > hypothesis has some chance to be real). Yes, the interaction with the NMI watchdog is unexpected and makes a processor erratum somewhat more likely. Paolo