From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751532AbdC1Lsq (ORCPT ); Tue, 28 Mar 2017 07:48:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38276 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751194AbdC1Lsm (ORCPT ); Tue, 28 Mar 2017 07:48:42 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com D1F2675EC6 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jpoimboe@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com D1F2675EC6 Date: Tue, 28 Mar 2017 06:46:17 -0500 From: Josh Poimboeuf To: Paolo Bonzini Cc: rkrcmar@redhat.com, x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [PATCH] kvm/x86/vmx: report KVM_SYSTEM_EVENT_CRASH on triple fault Message-ID: <20170328114617.zapicqltmtarv4jt@treble> References: <2101391670.8452799.1490687461888.JavaMail.zimbra@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <2101391670.8452799.1490687461888.JavaMail.zimbra@redhat.com> User-Agent: Mutt/1.6.0.1 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 28 Mar 2017 11:46:19 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 28, 2017 at 03:51:01AM -0400, Paolo Bonzini wrote: > > > While debugging a kernel issue, I found that QEMU always reboots when an > > x86 triple fault occurs, which complicates debugging. QEMU and libvirt > > have a facility for creating a dump when KVM reports > > KVM_SYSTEM_EVENT_CRASH. So change the VMX triple fault handler to do > > that. This gives user space the ability to decide whether to dump, > > pause, shutdown, or reboot. > > You probably want QEMU's -no-reboot option. > > Triple faults are already reported to userspace with KVM_EXIT_SHUTDOWN, > and it's up to userspace to decide what to do with it. This patch cannot > be applied, because there are guests that do a triple-fault intentionally > in order to reset the machine. Ok. Any idea how to force libvirt to create a dump? It has a 'coredump-destroy' option, but that only seems to work with 'on_crash': https://libvirt.org/formatdomain.html#elementsEvents -- Josh