From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60861) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VbtgG-0005ek-So for qemu-devel@nongnu.org; Thu, 31 Oct 2013 10:57:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Vbtg8-0004xC-Gl for qemu-devel@nongnu.org; Thu, 31 Oct 2013 10:57:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50623) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vbtg8-0004x6-7J for qemu-devel@nongnu.org; Thu, 31 Oct 2013 10:56:56 -0400 Message-ID: <52726FAA.6000502@redhat.com> Date: Thu, 31 Oct 2013 15:56:42 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1377187852-11192-1-git-send-email-pbonzini@redhat.com> <20131024023903.GD16757@G08FNSTD100614.fnst.cn.fujitsu.com> <20131031143004.GA9948@redhat.com> <52726A0B.4080805@redhat.com> <52726B95.6020006@redhat.com> <20131031145234.GC9948@redhat.com> In-Reply-To: <20131031145234.GC9948@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] pvpanic plans? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: pkrempa@redhat.com, lersek@redhat.com, marcel.a@redhat.com, libvir-list@redhat.com, Hu Tao , qemu-devel@nongnu.org, armbru@redhat.com, rhod@redhat.com, kraxel@redhat.com, anthony@codemonkey.ws, lcapitulino@redhat.com, afaerber@suse.de Il 31/10/2013 15:52, Michael S. Tsirkin ha scritto: >> > Yes, it does. > What does it break exactly? The point of a panicked event is to examine the guest at a particular moment in time (e.g. host-initiated crash dump). If you let the guest run, it may reboot and prevent you from getting a meaningful dump. >> > But I think that, once we make the pvpanic device is >> > optional, to a large extent there is no bug. Adding the pvpanic >> > device to the VM will make libvirt obey instead of the >> > in-guest setting, and that's it. >> > >> > Two months have passed and no casualties have been reported due to >> > pvpanic. Let's just remove the auto-pvpanic from all machine types in >> > 1.7 (yes, that's backwards incompatible in a strict sense), document >> > it in the release notes, and hope that the old QEMU versions with >> > mandatory pvpanic die of old age. > > Nod. I'm fine with that. > > I think we still need to do get rid of the PANICKED state somehow. > If we can't replace it with RUNNING state, let's replace it with PAUSED. > > For example, you can't continue from panicked for some reason. > You can't do a reset. But you can pause and then continue. We need to keep the PANICKED state, but we can make it a normal "resumable" state. Basically it's patches 1 and 2 at http://permalink.gmane.org/gmane.comp.emulators.qemu/229131. Rebasing will fix the problem highlighted in the commit message of patch 2. Paolo