From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51528) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WXKo6-00067G-7W for qemu-devel@nongnu.org; Mon, 07 Apr 2014 21:26:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WXKnt-0007ej-M4 for qemu-devel@nongnu.org; Mon, 07 Apr 2014 21:26:34 -0400 Received: from mail-pb0-f44.google.com ([209.85.160.44]:42944) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WXKnt-0007eS-HI for qemu-devel@nongnu.org; Mon, 07 Apr 2014 21:26:21 -0400 Received: by mail-pb0-f44.google.com with SMTP id rp16so255092pbb.31 for ; Mon, 07 Apr 2014 18:26:20 -0700 (PDT) Message-ID: <53435036.9020901@ozlabs.ru> Date: Tue, 08 Apr 2014 11:26:14 +1000 From: Alexey Kardashevskiy MIME-Version: 1.0 References: <1395888071-28677-1-git-send-email-aik@ozlabs.ru> <53341B8F.7040904@suse.de> <53341E41.7050101@ozlabs.ru> <533422AB.7080106@ozlabs.ru> In-Reply-To: <533422AB.7080106@ozlabs.ru> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH] target-ppc: Add @cpu_dt_id into migration stream List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: "qemu-ppc@nongnu.org" , =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= , QEMU Developers On 03/28/2014 12:07 AM, Alexey Kardashevskiy wrote: > On 03/27/2014 11:57 PM, Peter Maydell wrote: >> On 27 March 2014 12:49, Alexey Kardashevskiy wrote: >>> On 03/27/2014 11:37 PM, Andreas Färber wrote: >>>> Am 27.03.2014 03:41, schrieb Alexey Kardashevskiy: >>>>> This should prevent the destination guest from misbehaving when >>>>> the threads number is different in "-smp" command. >>>> >>>> Sorry, I don't understand. When migrating, surely -smp needs to be the >>>> same on source and destination, so how can they differ? >>> >>> >>> The idea is that "-smp" does not migrate and if we run source and >>> destination guests with different numbers in -smp, we end up with weird >>> machine >> >> Yes, so don't do that. As I understand it: >> (1) if you don't run QEMU with the exact same command line >> and config at both ends then migration won't work >> (2) we don't guarantee to detect and cleanly fail if you >> don't do (1) >> >> It would probably be nice if we did detect config mismatches, > > Yep, we do not send the device tree (as libvirt does). Pure command line > matching won't work. > >> but that seems to me like a problem we should be addressing >> more globally than just for one particular config item for >> one particular target... Ok. So. Let's assume I want to implement migration of "-smp" parameters. What would be the correct way of doing this in terms of the current QOM principles? Thanks. > > This is lot bigger that the issue I am trying to solve by this patch... > Still nack? -- Alexey