RE: [RFC v1 3/9] KVM: x86: Implement MSR_IA32_PEBS_ENABLE read/write emulation

[Kang, Luwei]

> > +   case MSR_IA32_PEBS_ENABLE:
> > +   if (pmu->pebs_enable == data)
> > +   return 0;
> > +   if (!(data & pmu->pebs_enable_mask) &&
> > +(data & MSR_IA32_PEBS_OUTPUT_MASK) ==
> > +   MSR_IA32_PEBS_OUTPUT_PT)
> {
> > +   pebs_enable_changed(pmu, data);
> > +   return 0;
> > +   }
> 
> Need #GP for bad values

Yes, this function will return 1 if neither of above two conditions check are 
not true. And will inject a #GP to guest.

Thanks,
Luwei Kang

Re: [RFC v1 3/9] KVM: x86: Implement MSR_IA32_PEBS_ENABLE read/write emulation

[Andi Kleen]

> + case MSR_IA32_PEBS_ENABLE:
> + if (pmu->pebs_enable == data)
> + return 0;
> + if (!(data & pmu->pebs_enable_mask) &&
> +  (data & MSR_IA32_PEBS_OUTPUT_MASK) ==
> + MSR_IA32_PEBS_OUTPUT_PT) {
> + pebs_enable_changed(pmu, data);
> + return 0;
> + }

Need #GP for bad values