From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52258) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dT4ii-0001ct-8S for qemu-devel@nongnu.org; Thu, 06 Jul 2017 07:13:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dT4if-00039Z-3f for qemu-devel@nongnu.org; Thu, 06 Jul 2017 07:13:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59346) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dT4ie-00039Q-TD for qemu-devel@nongnu.org; Thu, 06 Jul 2017 07:13:13 -0400 Date: Thu, 6 Jul 2017 12:13:06 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20170706111305.GA3174@work-vm> References: <1499237876.3041.4.camel@linux.intel.com> <20170705110431.GE22008@redhat.com> <20170705114411.GE29382@lemon.lan> <20170705122200.GH29382@lemon.lan> <20170706104940.GJ3988@redhat.com> <20170706110627.GK3988@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170706110627.GK3988@redhat.com> Subject: Re: [Qemu-devel] change x86 default machine type to Q35? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: Thomas Huth , Chao Peng , "Tian, Kevin" , Fam Zheng , qemu-devel@nongnu.org * Daniel P. Berrange (berrange@redhat.com) wrote: > On Thu, Jul 06, 2017 at 01:00:53PM +0200, Thomas Huth wrote: > > On 06.07.2017 12:49, Daniel P. Berrange wrote: > > [...] > > > This avoids the user having problems with guest ABI silently changing > > > behind their back, or migration suddenly failing to load vm state, > > > > For proper migration, you've got to specify the right versioned machine > > type anyway, so that should not be an issue here. > > That's only true if you have mis-matched QEMU releases on each host. > If you know you have the same QEMU release everywhere, there's no > need for versioned machine types. Though obviously we'd still recommend > people us versioned machine type, its not unreasonable that some people > will not We have got protection against machine type screwups; e.g going from -M pc to -M q35 we get: qemu-system-x86_64: Machine type received is 'pc-i440fx-2.9' and local is 'pc-q35-2.9' Dave > Regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK