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From:   Jim Mattson <jmattson@google.com>
Date:   Fri, 27 Jul 2018 14:30:24 -0700
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Subject: Re: [PATCH v14 8/9] KVM: x86: virtualize cpuid faulting
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Kyle Huey <me@kylehuey.com>,
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On Fri, Jul 27, 2018 at 2:05 PM, Andy Lutomirski <luto@kernel.org> wrote:
> Does KVM *have* a concept of "maximum non-turbo frequency" of the
> guest that it would make sense to expose here?  If so, presumably the
> right solution is to expose it.

KVM has the concept of a guest's invariant TSC frequency. The Maximum
Non-Turbo Ratio is just some fraction of that. Sadly, the fraction is
100 MHz, 133.33MHz, or the "scalable bus frequency" from some other
MSR, depending on microarchitecture.