[PATCH 0/2] kvm: disable virtualization on kdump

Eduardo Habkost ehabkost at redhat.com
Mon Oct 27 11:50:03 EDT 2008

On Mon, Oct 27, 2008 at 08:05:50AM -0700, Eric W. Biederman wrote:
> Avi Kivity <avi at redhat.com> writes:
> > There's no way to query whether vmx is enabled or disabled, AFAICT.  So we have
> > to execute vmxoff and ignore possible #UDs.
> >
> > If we trust the exception handlers, there's no problem.  Otherwise we need to
> > replace the current #UD handler with an iret (perhaps switching temporarily to
> > another IDT).
> Ugh.  We already change the IDT on that code path so that
> may be a way to go.

I don't see the IDT being changed on native_machine_shutdown(). It even
uses notifier chain registration (register_die_notifier()) to sneak a
NMI handler in.


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