Re: [PATCH 17/22] KVM: x86/mmu: pull struct kvm_pagewalk out of struct kvm_mmu

[Yosry Ahmed]

> @@ -6767,11 +6748,11 @@ int kvm_mmu_create(struct kvm_vcpu *vcpu)
>
>         vcpu->arch.mmu = &vcpu->arch.root_mmu;
>
> -       ret = __kvm_mmu_create(vcpu, &vcpu->arch.guest_mmu);
> +       ret = __kvm_mmu_create(vcpu, &vcpu->arch.guest_mmu, &vcpu->arch.tdp_walk);
>         if (ret)
>                 return ret;
>
> -       ret = __kvm_mmu_create(vcpu, &vcpu->arch.root_mmu);
> +       ret = __kvm_mmu_create(vcpu, &vcpu->arch.root_mmu, &vcpu->arch.cpu_walk);
>         if (ret)
>                 goto fail_allocate_root;

I admittedly did not take a close look at the series. Just wanted to
chime in about naming. I *love* that we are getting rid of nested_mmu
because I can never immediately tell the difference between guest_mmu
and nested_mmu, so thank you for that.

However, I can't immediately tell what vcpu->arch.cpu_walk is doing
either (compared to vcpu->arch.tdp_walk), so maybe the names can be
improved? If these walks are tied to these MMUs, maybe name them as
such (e.g. root_pg_walk and guest_pg_walk)?

I also think root_mmu and guest_mmu could still use some improvement
but that's probably outside the scope of this series. These are
essentially L1 MMU and L2 MMU, right? Maybe just mmu and nested_mmu
could work? But I am not sure if we can reclaim the nested_mmu name,
it's gonna screw with anyone doing backports :/