> diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
> index 122bfc0124d3..e9d4d7b66111 100644
> --- a/arch/x86/kvm/mmu/paging_tmpl.h
> +++ b/arch/x86/kvm/mmu/paging_tmpl.h
> @@ -646,6 +646,17 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault,
> if (WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root.hpa)))
> goto out_gpte_changed;
>
> + /*
> + * Load a new root and retry the faulting instruction in the extremely
> + * unlikely scenario that the guest root gfn became visible between
> + * loading a dummy root and handling the resulting page fault, e.g. if
> + * userspace create a memslot in the interim.
> + */
> + if (unlikely(kvm_mmu_is_dummy_root(vcpu->arch.mmu->root.hpa))) {
> + kvm_mmu_unload(vcpu);
Do we really need a kvm_mmu_unload()? Could we just set
vcpu->arch.mmu->root.hpa to INVALID_PAGE here?
> + goto out_gpte_changed;
> + }
> +
> for_each_shadow_entry(vcpu, fault->addr, it) {
> gfn_t table_gfn;
B.R.
Yu
