Re: [RFC 11/19] KVM: x86/mmu: Factor shadow_zero_check out of make_spte

[Paolo Bonzini]

On 11/18/21 19:02, Sean Christopherson wrote:
> > but that's not a great name because the former is used also when shadowing
> > EPT/NPT.  I'm thinking of standardizing on "shadow" and "TDP" (it's not
> > perfect because of the 32-bit and tdp_mmu=0 cases, but it's a start).  Maybe
> > even split parts of mmu.c out into shadow_mmu.c.
> But shadow is flat out wrong until EPT and NPT support is ripped out of the "legacy"
> MMU.

Yeah, that's true.  "full" MMU? :)

> > - the two walkers (I'm quite convinced of splitting that part out of struct
> > kvm_mmu and getting rid of walk_mmu/nested_mmu): that's easy, it can be
> > walk01 and walk12 with "walk" pointing to one of them
>
> I am all in favor of walk01 and walk12, the guest_mmu vs. nested_mmu confusion
> is painful.
>
> > - the two MMUs: with nested_mmu gone, root_mmu and guest_mmu are much less
> > confusing and we can keep those names.
>
> I would prefer root_mmu and nested_tdp_mmu.  guest_mmu is misleading because its
> not used for all cases of sp->role.guest_mode=1, i.e. when L1 is not using TDP
> then guest_mode=1 but KVM isn't using guest_mmu.

Ok, that sounds good too.

Paolo