From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eduardo Habkost Subject: Re: [Qemu-devel] [uq/master PATCH 0/7] x86 CPU subclasses, take 7 Date: Fri, 31 Jan 2014 16:51:37 -0200 Message-ID: <20140131185137.GD2221@otherpad.lan.raisama.net> References: <1391111339-6958-1-git-send-email-ehabkost@redhat.com> <20140131154853.34c41154@thinkpad> <52EBB82F.7020001@redhat.com> <20140131151753.GY2221@otherpad.lan.raisama.net> <20140131170621.3857e584@thinkpad> <20140131164207.GZ2221@otherpad.lan.raisama.net> <52EBD4E9.2000700@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Igor Mammedov , qemu-devel@nongnu.org, kvm@vger.kernel.org, libvir-list@redhat.com, Jiri Denemark , Andreas =?iso-8859-1?Q?F=E4rber?= To: Paolo Bonzini Return-path: Received: from mx1.redhat.com ([209.132.183.28]:2127 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932281AbaAaSvn (ORCPT ); Fri, 31 Jan 2014 13:51:43 -0500 Content-Disposition: inline In-Reply-To: <52EBD4E9.2000700@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Fri, Jan 31, 2014 at 05:52:57PM +0100, Paolo Bonzini wrote: > Il 31/01/2014 17:42, Eduardo Habkost ha scritto: > >>> It looks like only -device would be able to create actual CPU models, > >>> but for -device to work we need as minimum this series and conversion > >>> of CPU features to properties in tree. Then I guess we can override > >>> cannot_instantiate_with_device_add_yet for x86 CPUs. > >Setting cannot_instantiate_with_device_add_yet=false looks much simpler > >than implementing UserCreatable. My question is: may we do that, already > >(once this series gets included), or is there something else holding us > >from doing it? > > Once you make something creatable with "-object", the API must not > change anymore. So we would have to think twice about that. > > Allowing -device may be okay, since in the (very?) long term -device > can be replaced by -object. But -object is definitive. OK, one additional reason to try device_add first. But then we have one additional problem: * We want to allow libvirt to probe for CPU model information when running QEMU using "-machine none" (because libvirt already does that, and we don't want to require libvirt to run QEMU multiple times) * "device_add driver=-x86_64-cpu" requires an icc-bus to be present * -machine none doesn't have any bus * I don't see a way to create an icc-bus through QMP (is there a way?) -- Eduardo