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RE: [Xen-devel] [PATCH] pvcpuid: mask TSC invariant bit for various circumstances

>>> Dan Magenheimer <dan.magenheimer@xxxxxxxxxx> 28.10.09 17:27 >>>
>But, that said, I'm still not convinced my patch is the
>right answer.  If possible (e.g. using the CPUID masking
>feature Jan referred to), Xen should always hide the TSC

Actually I just realized that this feature would probably not help you
at all: The bit you're after is in leaf 0x80000007, but the masking applies
only to leaf 1 (plus 0x80000001 for AMD).

>Invariant bit from all guests (OS's and apps) and only
>expose it via pvcpuid or some other mechanism.
>Otherwise an OS or app may make false assumptions
>based on an architecturally-specified cpuid bit.

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