On Wed, Apr 13, 2022 at 5:31 AM Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > union kvm_mmu_page_role { > > u32 word; > > @@ -331,7 +331,8 @@ union kvm_mmu_page_role { > > unsigned smap_andnot_wp:1; > > unsigned ad_disabled:1; > > unsigned guest_mode:1; > > - unsigned :6; > > + unsigned glevel:4; > > We don't need 4 bits for this. Crossing our fingers that we never had to shadow > a 2-level guest with a 6-level host, we can do: > > unsigned passthrough_delta:2; We can save the bits in the future when we need more bits so I didn't hesitate to use 4 bits since glevel gives simple code. ^_^ I think the name passthrough_delta is more informative and glevel is used only for comparison so passthrough_delta can also be simple. I will apply your suggestion. Thanks Lai