Re: [libvirt] [Qemu-devel] [PATCH RFC 4/8] target-i386: cpu: consolidate calls of object_property_parse() in x86_cpu_parse_featurestr
On Fri, 3 Jun 2016 09:30:09 +0200
Peter Krempa <pkrempa(a)redhat.com> wrote:
On Thu, Jun 02, 2016 at 18:31:04 +0200, Igor Mammedov wrote:
> On Thu, 2 Jun 2016 17:05:06 +0200
> Peter Krempa <pkrempa(a)redhat.com> wrote:
> > On Thu, Jun 02, 2016 at 11:53:22 -0300, Eduardo Habkost wrote:
> > > On Thu, Jun 02, 2016 at 02:22:22PM +0200, Igor Mammedov wrote:
[...]
> > I couldn't find anything regarding xlevel (so we might actually not
> > support it at all), but we indeed do limit the hv_spinlock count:
> >
> >
> > if (def->hyperv_spinlocks < 0xFFF) {
> > virReportError(VIR_ERR_XML_ERROR, "%s",
> > _("HyperV spinlock retry count must be
"
> > "at least 4095"));
> > goto error;
> > }
> >
> > Peter
> Peter,
> Does libvirt still uses -cpu xxx,+feat1,-feat2 syntax
> or canonical property syntax there feat1=on,feat2=off
We use the legacy one:
-cpu core2duo,+ds,+acpi,+ht,+tm,+ds_cpl, ...
and
-cpu 'qemu32,hv_relaxed,hv_vapic, ...
for the hyperv features.
We probably can switch to the new one if there's a reasonable way how to
detect that qemu is supporting the new one.
for x86 features became properties
since 2.4 release (commit 38e5c119),
that's the one way to know it.
But it's still only +-features for sparc (that's the last remaining
target that has legacy parsing).
Another way to detect it is to probe via QOM if CPU has a property corresponding
to a feature.
Maybe Eduardo knows about other ways to do it.
Peter