Re: [Qemu-devel] [RFC 7/7] target-i386: Disable direct passthrough of PMU CPUID leaf by default

[Igor Mammedov <imammedo@redhat.com>]

On Fri, 26 Apr 2013 17:33:18 +0200
Andreas Färber <afaerber@suse.de> wrote:

> 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 <ehabkost@redhat.com> 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/discarded after
> >> converting to the rest to properties and sub-classes.
> > 
> > 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.
> 
> 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 done
> during Hard Freeze. :)
patch "[PATCH 02/10] target-i386: cpu: convert existing dynamic properties
into static properties" should be enough for using model,level compat
properties.

> 
> Andreas
> 
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> 


-- 
Regards,
  Igor