Re: [PATCH]: Fix MSR_K7_EVNTSEL{0,3} for SVM

Joerg Roedel
2008-04-28T15:57:53Z

On Mon, Apr 28, 2008 at 10:17:37AM -0400, Chris Lalancette wrote:
> Joerg Roedel wrote:
> > We already discussed the emulation of the performance counter registers
> > in the past. The conclusion is, that we loose live migration with that
> > emulation because performance monitoring is implemented differently
> > between AMD and Intel systems. Maybe discarding _any_ writes to
> > the performance counter MSRs will fix the guest crash. What we should
> > not do is injecting GPF on zero writes to the MSRs because that will
> > break Windows XP 64bit installation.
>
> OK, yeah, I read some of those threads over the weekend. It is a larger
> problem than just this crash, and probably one to be solved later.
> I have attached a patch which just discards all writes, as you suggested;
> this allows my RHEL-4 guest to successfully boot, although obviously the NMI
> watchdog which it thinks it set up is not actually working. Joerg, can you test
> this on your 64-bit Windows XP guest to make sure it is still working?

XP 64 bit installs and works fine with your patch.

Joerg

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