Re: [RFC] nmi watchdog in kvm

Ingo Molnar
2008-01-28T10:57:46Z

* Balaji Rao <balajirrao-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:

> I was trying to enable the use of nmi watchdog within a linux guest
> running in kvm. I have done it by allowing direct access to perfmon
> msrs using the MSR_BITMAP field in vmcs region.

your patch looks pretty clean and simple to me - and it would make quite
a bit of sense from the "completeness of architecture" POV to inject
NMIs into KVM - even though it's obviously not that hard to interrupt a
KVM guest context via other means ;-)

at the least this would test the correctness of guest kernel NMI
handling. We could even test things by injecting a very large stream of
NMIs, which is not that easy on native hardware, etc.

( the emulation of "NMI reason" IO port could be accelerated too
perhaps, instead of passing it over to qemu. )

so it's a good idea IMO.

Ingo