Re: [PATCH] kvm tools: Add 'kvm nmi' command

[Gleb Natapov <gleb@redhat.com>]

On Wed, Dec 07, 2011 at 02:37:25PM +0400, Cyrill Gorcunov wrote:
> On Wed, Dec 07, 2011 at 12:33:05PM +0200, Gleb Natapov wrote:
> > On Wed, Dec 07, 2011 at 02:31:11PM +0400, Cyrill Gorcunov wrote:
> > > On Wed, Dec 07, 2011 at 12:21:52PM +0200, Gleb Natapov wrote:
> > > > On Tue, Dec 06, 2011 at 10:42:55PM +0200, Sasha Levin wrote:
> > > > > +static void handle_nmi(int fd, u32 type, u32 len, u8 *msg)
> > > > > +{
> > > > > +	u32 vcpu = *(u32 *)msg;
> > > > > +
> > > > > +	ioctl(kvm_cpus[vcpu]->vcpu_fd, KVM_NMI);
> > > >
> > > > You need to check that vcpu apic's LINT1 is configured to receive
> > > > NMI (and not masked obviously) before injecting NMI. 
> > > > 
> > > 
> > > I've been configuring mptable to have lint1 as nmi receiver,
> > > so it should remain so I suppose (if only we've not masked it
> > > somewhere else ;)
> > > 
> >
> > That's up to the guest. mptable is just a hint to an OS on how things is
> > wired in HW.
> > 
> 
> Yup, but while we support linux kernels only it should be fine. Still
> of course on long term we need a check.
> 
Tomorrow someone will send a patch to change how Linux behaves and
slightly older kvmtool will not be able to run newer kernels :) No need
to wait for long term, a couple of lines of code will fix the issue in the
patch. Look here for reference:

http://article.gmane.org/gmane.comp.emulators.kvm.devel/80339

--
			Gleb.