From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:51307) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QgISM-0001X7-Gs for qemu-devel@nongnu.org; Mon, 11 Jul 2011 11:31:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QgISL-00052o-0v for qemu-devel@nongnu.org; Mon, 11 Jul 2011 11:31:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:16735) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QgISK-00051y-Fk for qemu-devel@nongnu.org; Mon, 11 Jul 2011 11:31:32 -0400 Message-ID: <4E1B174F.3010406@redhat.com> Date: Mon, 11 Jul 2011 17:31:27 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <4E148776.4000805@redhat.com> <4E1497C6.4060505@codemonkey.ws> <4E15CF88.8080404@redhat.com> <4E1B1779.6080505@redhat.com> In-Reply-To: <4E1B1779.6080505@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] migration: new sections and backward compatibility. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: Juan Quintela , "qemu-devel@nongnu.org" , jes sorensen , Alexander Graf , Markus Armbruster , Gerd Hoffmann On 07/11/2011 05:32 PM, Kevin Wolf wrote: >>> I'd guess the best would be to have a special VMSTATE that means >>> "broken old version doesn't send a section" which we can set for >>> special -M? >> >> No, the best would be to have a serious migration format, based for >> example on ASN.1 which Michael Tsirkin was playing with. We cannot keep >> bolting more and more stuff on top of the current protocol, especially >> since adding a new protocol is not that hard (old machine types can keep >> the old protocol). > > And even more so with the old format being ambiguous. We haven't decided > yet what to do with subsections of structs, have we? I hope to test this week the prototype I sent. Paolo