Re: [Qemu-devel] [PATCH RFC 4/8] target-i386: cpu: consolidate calls of object_property_parse() in x86_cpu_parse_featurestr

[Igor Mammedov <imammedo@redhat.com>]

On Thu, 2 Jun 2016 17:05:06 +0200
Peter Krempa <pkrempa@redhat.com> wrote:

> On Thu, Jun 02, 2016 at 11:53:22 -0300, Eduardo Habkost wrote:
> > (CCing libvirt folks)
> > 
> > BTW:
> > 
> > On Thu, Jun 02, 2016 at 02:22:22PM +0200, Igor Mammedov wrote:
> > [...]  
> > > >         /* Special cases: */
> > > >         if (!strcmp(name, "xlevel")) {
> > > >             numvalue = strtoul(val, &err, 0);
> > > >             if (!*val || *err) {
> > > >                 error_setg(errp, "bad numerical value %s", val);
> > > >                 return;
> > > >             }
> > > >             if (numvalue < 0x80000000) {
> > > >                 error_report("xlevel value shall always be >= 0x80000000"
> > > >                              ", fixup will be removed in future versions");
> > > >                 numvalue += 0x80000000;
> > > >             snprintf(num, sizeof(num), "%" PRIu32, numvalue);
> > > >             val = num;  
> > [...]  
> > > >         } else if (!strcmp(name, "hv-spinlocks")) {
> > > >             const int min = 0xFFF;
> > > > 
> > > >             numvalue = strtoul(val, &err, 0);
> > > >             if (!*val || *err) {
> > > >                 error_setg(errp, "bad numerical value %s", val);
> > > >                 return;
> > > >             }
> > > >             if (numvalue < min) {
> > > >                 error_report("hv-spinlocks value shall always be >= 0x%x"
> > > >                              ", fixup will be removed in future versions",
> > > >                              min);
> > > >                 numvalue = min;
> > > >             }  
> > 
> > Those "fixup will be removed in future versions" warnings are
> > present since QEMU 1.7. Assuming that libvirt never allowed those
> > invalid values to be used in the configuration (did it?), I
> > believe we can safely remove the hv-spinlocks and xlevel fixups
> > in QEMU 2.7.  
> 
> 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