Re: [PATCH 00/11] KVM: fix issues with stale control fields

[Sean Christopherson]

On Sat, Sep 26, 2026, Paolo Bonzini wrote:
> > Fix two bugs where the guest could do stupid things on purpose to
> > cause problems in the host.
> >
> > Patches 1-5 cover cases where actions done through VMCB control fields
> > have to be redone if VMRUN fails.  In particular, failed VMRUNs can
> > cause pending TLB flushes to be dropped.
> >
> > Patch 6 fixes a case where eVMCS execution controls can cause the
> > host to use a stale MSR permission bitmap.  Patches 7-11 are tests
> > for nested x2APIC; don't run them on an unpatched kernel.
> 
> In addition to what was reported by Sashiko, the test does not pass on
> SVM.  Fixed as follows:

Thanks for cleaning up the mess!  I was definitely getting too greedy trying to
get bonus coverage on AMD (and I've been ignoring the SVM failures in my local
testing for an embarrasingly long time).