From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:43230) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UVme4-00072q-Bw for qemu-devel@nongnu.org; Fri, 26 Apr 2013 13:41:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UVme2-0007Bl-Ug for qemu-devel@nongnu.org; Fri, 26 Apr 2013 13:41:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34140) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UVme2-0007Bc-LA for qemu-devel@nongnu.org; Fri, 26 Apr 2013 13:41:14 -0400 Date: Fri, 26 Apr 2013 19:41:10 +0200 From: Igor Mammedov Message-ID: <20130426194110.43ff3a80@thinkpad> In-Reply-To: <20130426173040.GK11821@otherpad.lan.raisama.net> References: <1366915386-14728-1-git-send-email-ehabkost@redhat.com> <1366915386-14728-8-git-send-email-ehabkost@redhat.com> <20130426171029.3e159116@thinkpad> <20130426153108.GX2900@otherpad.lan.raisama.net> <517A9E3E.2060901@suse.de> <20130426173915.20d02c7d@thinkpad> <20130426173040.GK11821@otherpad.lan.raisama.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [RFC 7/7] target-i386: Disable direct passthrough of PMU CPUID leaf by default List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eduardo Habkost Cc: Andreas =?ISO-8859-1?B?RuRyYmVy?= , Gleb Natapov , qemu-devel@nongnu.org On Fri, 26 Apr 2013 14:30:40 -0300 Eduardo Habkost wrote: > On Fri, Apr 26, 2013 at 05:39:15PM +0200, Igor Mammedov wrote: > > On Fri, 26 Apr 2013 17:33:18 +0200 > > Andreas F=E4rber wrote: > >=20 > > > Am 26.04.2013 17:31, schrieb Eduardo Habkost: > > > > On Fri, Apr 26, 2013 at 05:10:29PM +0200, Igor Mammedov wrote: > > > >> On Thu, 25 Apr 2013 15:43:06 -0300 > > > >> Eduardo Habkost wrote: > > > >> > > > >>> The current code handling the CPUID 0xA leaf simply forwards all = data > > > >>> from GET_SUPPORTED_CPUID directly to the guest, breaking migration > > > >>> between hosts with different number of PMU counters. > > > >>> > > > >>> This patch disables this behavior, except on older machine-types = (for > > > >>> compatibility) and on the "host" CPU model. > > > >> Please, make it static property and use compat properties. > > > >> Result will be simpler and much less will have to be redone/disca= rded after > > > >> converting to the rest to properties and sub-classes. > > > >=20 > > > > I was going to say that static properties were too much work to be = done > > > > in time for 1.5, but you are right: in this specific case adding a > > > > static property for the cpuid_pmu_passthrough field looks very easy= . I > > > > will give it a try. > > >=20 > > > I am hoping to get as initial set (though not all) of the static > > > properties still into 1.5. Using them to fix CPUID bugs can then be d= one > > > during Hard Freeze. :) > > patch "[PATCH 02/10] target-i386: cpu: convert existing dynamic propert= ies > > into static properties" should be enough for using model,level compat > > properties. >=20 > ...except that we don't have X86CPU model subclasses yet, so we can't > set model-specific compat properties using compat_props. X86CPU could serve here >=20 > Maybe we can make compat_props work for pmu-passthrough, but it may be > not completely straightforward because I would like to keep it enabled > by default on -cpu host. Maybe for 'host' hack realize() to override default, will do and later we can move it to host_subclass. it's easier to re-factor than compact functions >=20 > --=20 > Eduardo >=20 --=20 Regards, Igor