Re: [PATCH 2/2] KVM: x86: Suppress WARNs on nested_run_pending after userspace exit

[Sean Christopherson <seanjc@google.com>]

On Tue, Mar 10, 2026, Yosry Ahmed wrote:
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 879cdeb6adde..cad16c83dcff 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -12090,6 +12090,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
> >         if (r <= 0)
> >                 goto out;
> >
> > +       /*
> > +        * If userspace may have modified vCPU state, mark nested_run_pending
> > +        * as "untrusted" to avoid triggering false-positive WARNs.
> > +        */
> > +       if (vcpu->arch.nested_run_pending == KVM_NESTED_RUN_PENDING)
> > +               vcpu->arch.nested_run_pending = KVM_NESTED_RUN_PENDING_UNTRUSTED;
> > +
> 
> Why not inside kvm_x86_vcpu_pre_run()?

That, is a very good question.  /facepalm