On Sat, 2021-11-20 at 17:48 +0200, Mika Penttilä wrote:
> > @@ -9785,6 +9787,14 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
> >        local_irq_disable();
> >        vcpu->mode = IN_GUEST_MODE;
> >    
> > +     /*
> > +      * If the guest requires direct access to mapped L1 pages, check
> > +      * the caches are valid. Will raise KVM_REQ_GET_NESTED_STATE_PAGES
> > +      * to go and revalidate them, if necessary.
> > +      */
> > +     if (is_guest_mode(vcpu) && kvm_x86_ops.nested_ops->check_guest_maps)
> > +             kvm_x86_ops.nested_ops->check_guest_maps(vcpu);
> 
> But KVM_REQ_GET_NESTED_STATE_PAGES is not check until next 
> vcpu_enter_guest() entry ?

Sure, but that's why this call to ->check_guest_maps() comes just a few
lines *before* the 'if (kvm_cpu_exit_request(vcpu))' that will bounce
us back out so that we go through vcpu_enter_guest() from the start
again?