From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=45161 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pq3Ce-0008Ra-SZ for qemu-devel@nongnu.org; Thu, 17 Feb 2011 07:43:25 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pq3Cd-0004BC-Cv for qemu-devel@nongnu.org; Thu, 17 Feb 2011 07:43:24 -0500 Received: from mx1.redhat.com ([209.132.183.28]:19068) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pq3Cd-0004B6-40 for qemu-devel@nongnu.org; Thu, 17 Feb 2011 07:43:23 -0500 Date: Thu, 17 Feb 2011 18:12:24 +0530 From: Amit Shah Subject: Re: [Qemu-devel] KVM call minutes for Feb 15 Message-ID: <20110217124224.GA27487@amit-x200.redhat.com> References: <20110215162629.GN21720@x200.localdomain> <4D5B0889.4030303@codemonkey.ws> <20110216143934.GB5770@amit-x200.redhat.com> <4D5BE217.2020306@codemonkey.ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4D5BE217.2020306@codemonkey.ws> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: Chris Wright , qemu-devel@nongnu.org, kvm@vger.kernel.org On (Wed) 16 Feb 2011 [08:41:27], Anthony Liguori wrote: > On 02/16/2011 08:39 AM, Amit Shah wrote: > >On (Tue) 15 Feb 2011 [17:13:13], Anthony Liguori wrote: > >>On 02/15/2011 10:26 AM, Chris Wright wrote: > >>>revisit new -> old migration > >>>- Amit offers virtio-serial patches and some legwork > >>So, to me, migration correctness trumps compatibility. I don't > >>think compatibility is useful if it means that a guest may fail > >>during migration. We have subsections as a way to support the cases > >>where it's safe to migrate to an old version only if a feature is > >>not being used or a corner case is not currently happening. This is > >>the best way to approach the problem. > >> > >>If a subsection won't work, that means you want to migrate when > >>you're completely sure that migrating will break a guest. That > >>doesn't seem reasonable at all to me. > >> > >>I think in the last discussion on Amit's patches, I had suggested > >>that subsections could be used to allow migration when there wasn't > >>any queued data. I think this is the best we can do while > >>preserving correctness. > >The only problem is that virtio hasn't been converted over to vmstate, > >which is necessary for subsections. > > Then it needs to be converted. But that can't be done for 0.14. Amit