From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60050) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VC4uR-0004fv-Em for qemu-devel@nongnu.org; Wed, 21 Aug 2013 05:41:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VC4uL-0005kT-FT for qemu-devel@nongnu.org; Wed, 21 Aug 2013 05:40:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:22572) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VC4uL-0005kG-5i for qemu-devel@nongnu.org; Wed, 21 Aug 2013 05:40:53 -0400 Date: Wed, 21 Aug 2013 12:42:37 +0300 From: "Michael S. Tsirkin" Message-ID: <20130821094237.GA4757@redhat.com> References: <1376233843-19410-1-git-send-email-marcel.a@redhat.com> <520B2B8D.8070401@redhat.com> <1377072197.1888.35.camel@localhost.localdomain> <521477CF.4010703@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <521477CF.4010703@redhat.com> Subject: Re: [Qemu-devel] [PATCH for-1.6 V2 0/2] pvpanic: Separate pvpanic from machine type List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: aliguori@us.ibm.com, gleb@redhat.com, Marcel Apfelbaum , hutao@cn.fujitsu.com, qemu-devel@nongnu.org, Ronen Hod , kraxel@redhat.com, afaerber@suse.de, vrozenfe@redhat.com On Wed, Aug 21, 2013 at 10:18:23AM +0200, Paolo Bonzini wrote: > Il 21/08/2013 10:03, Marcel Apfelbaum ha scritto: > > On Wed, 2013-08-14 at 10:02 +0300, Ronen Hod wrote: > >> How about adding a flag that tells QEMU whether to pause or reboot the guest > >> after the panic? > >> We cannot assume that we always have a management layer that takes care > >> of this. > >> One example is Microsoft's WHQL that deliberately generates a BSOD, and then > >> examines the dump files. > > After this patch the pvpanic is not part of the global devices anymore so just > > don't enable it if you want to reboot on BSOD. > > In my opinion "reboot after panic" equals "run without pvpanic device" > > This is not entirely possible, since "reboot after panic" is a guest > setting while "run without pvpanic device" is a host setting (that the > guest administrator may not even have access to: Ronen's case is a good > example of this, because the "administrator" there is the WHQL harness). > > However, I think this is a driver problem. The driver should just probe > the "reboot after panic" setting and not issue the outb to the pvpanic port. > > Paolo This might or might not be possible on different OS-es. What exactly is gained by doing vmstop on outb of pvpanic? We want a notification about the panic but adding yet another way to halt seems kind of useless. Why not let VM continue? If it wants to stop it can always call halt.