Re: [PATCH v9 7/7] KVM: x86: virtualize cpuid faulting

[Thomas Gleixner]

On Tue, 8 Nov 2016, Kyle Huey wrote:
> > It will simplify the MSR get/set code, and make it easier to plumb
> > support for new bits in these MSRs.
> 
> I'm inclined to do this for MSR_PLATFORM_INFO but not
> MSR_MISC_FEATURES_ENABLES.  The former actually has other bits, and
> isn't used outside the msr handling code (yet, anyways).
> MSR_MISC_FEATURES_ENABLES doesn't have any other bits (it's actually
> not documented by Intel at all outside of that virtualization paper)
> and after masking bits in cpuid.c or adding a helper function the
> complexity would be a wash at best.

The feature MSR is also used for enabling ring3 MWAIT, which is obviously
not documented either. So there is more stuff coming along....

Thanks,

	tglx