Re: [PATCH V3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

From: Sheng Yang
Date: Mon Apr 19 2010 - 23:33:15 EST


On Monday 19 April 2010 16:25:17 Avi Kivity wrote:
> On 04/17/2010 09:12 PM, Avi Kivity wrote:
> > I think you were right the first time around.
>
> Re-reading again (esp. the part about treatment of indirect NMI
> vmexits), I think this was wrong, and that the code is correct. I am
> now thoroughly confused.
>
My fault...

To my understanding now, "If an event causes a VM exit directly, it does not
update architectural state as it would have if it had it not caused the VM
exit:", means: in NMI case, NMI would involve the NMI handler, and change the
"architectural state" to NMI block. In VMX non-root mode, the behavior of
calling NMI handler changed(determine by some VMCS fields), but not the
affection to the "architectural state". So the NMI block state would remain
the same.

--
regards
Yang, Sheng
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