Re: [Qemu-devel] [PATCH] qemu: fix cpuid eax for kvm cpu

[Michael S. Tsirkin]

On Tue, May 01, 2012 at 03:38:43PM +0300, Avi Kivity wrote:
> On 04/30/2012 05:42 PM, Michael S. Tsirkin wrote:
> > cpuid eax should return the max leaf so that
> > guests can find out the valid range.
> > This matches Xen et al.
> >
> > Tested using -cpu kvm64.
> >
> > Signed-off-by: Michael S. Tsirkin <address@hidden>
> > ---
> >  target-i386/kvm.c |    2 +-
> >  1 files changed, 1 insertions(+), 1 deletions(-)
> >
> > diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> > index e74a9e4..c097248 100644
> > --- a/target-i386/kvm.c
> > +++ b/target-i386/kvm.c
> > @@ -379,7 +379,7 @@ int kvm_arch_init_vcpu(CPUX86State *env)
> >      c->function = KVM_CPUID_SIGNATURE;
> >      if (!hyperv_enabled()) {
> >          memcpy(signature, "KVMKVMKVM\0\0\0", 12);
> > -        c->eax = 0;
> > +        c->eax = KVM_CPUID_FEATURES;
> >      } else {
> >          memcpy(signature, "Microsoft Hv", 12);
> >          c->eax = HYPERV_CPUID_MIN;
> 
> Should only change for -M 1.1+?

I don't think we should: it's a bug fix and we don't try to be bug for
bug compatible unless fixing the bug actually affects guest behaviour.

> -- 
> error compiling committee.c: too many arguments to function