From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56225) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WzQGz-0001lj-Db for qemu-devel@nongnu.org; Tue, 24 Jun 2014 08:56:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WzQGp-0005sA-Rz for qemu-devel@nongnu.org; Tue, 24 Jun 2014 08:56:29 -0400 Received: from mail-pb0-f49.google.com ([209.85.160.49]:35971) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WzQGp-0005ru-Mk for qemu-devel@nongnu.org; Tue, 24 Jun 2014 08:56:19 -0400 Received: by mail-pb0-f49.google.com with SMTP id rr13so223565pbb.8 for ; Tue, 24 Jun 2014 05:56:17 -0700 (PDT) Message-ID: <53A9756A.80801@ozlabs.ru> Date: Tue, 24 Jun 2014 22:56:10 +1000 From: Alexey Kardashevskiy MIME-Version: 1.0 References: <53A8366B.1020301@ozlabs.ru> <53A840C8.8060607@redhat.com> <53A89D98.3030708@ozlabs.ru> <53A9095B.3070803@redhat.com> <53A90E9C.2020300@ozlabs.ru> <87bnti202c.fsf@blackfin.pond.sub.org> <53A95F81.7070808@suse.de> In-Reply-To: <53A95F81.7070808@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] machines and versions - why so many? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= , Markus Armbruster Cc: Eduardo Habkost , Marcel Apfelbaum , "qemu-devel@nongnu.org" , Paul Mackerras , Paolo Bonzini , Alexander Graf On 06/24/2014 09:22 PM, Andreas Färber wrote: > Am 24.06.2014 10:17, schrieb Markus Armbruster: >> Back then gerd created a way to do the compatibility stuff without >> getting into the other target's hair: compat_props. They've served us >> well enough, but now that more targets get interested in migration, >> their shortcomings start to hurt. Having to duplicate device >> compatibility gunk in multiple places, all far away from the device, is >> decidedly suboptimal. Better ideas welcome. > > Might it make sense to reconsider the proposed machine type hierarchy > and have machine-2.2 <- pc-i440fx-2.2, with global properties in > machine-x.y types and pc_compat_x_y() taking care of PC inheritence? We > can't inherit from both pc-x.y and machine-x.y though, so probably not, > just throwing thoughts around. I wanted to suggest this but I do not want even think about multiple inheritance in QOM :) And in fact all I would possibly want for pseries from those versioned PCs is those PC_COMPAT_X_Y things with enforced device properties. -- Alexey