Re: [PATCH v14 8/9] KVM: x86: virtualize cpuid faulting

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Jul 27, 2018 at 2:30 PM, Jim Mattson <jmattson@xxxxxxxxxx> wrote:
> On Fri, Jul 27, 2018 at 2:05 PM, Andy Lutomirski <luto@xxxxxxxxxx> 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.

Which is problematic, unless KVM wants to start deciding what the base
clock is.  There's MSR_FSB_FREQ, which is supported on Atom only,
IIRC.

I really wish Intel would get its act together.
--
To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Wireless]     [Linux Kernel]     [ATH6KL]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Samba]     [Device Mapper]

  Powered by Linux