Re: [PATCH 10/12] KVM: MMU: load new PGD after the shadow MMU is initialized

[Paolo Bonzini]

On 2/11/22 18:45, Sean Christopherson wrote:
> On Wed, Feb 09, 2022, Paolo Bonzini wrote:
> > Now that __kvm_mmu_new_pgd does not look at the MMU's root_level and
> > shadow_root_level anymore, pull the PGD load after the initialization of
> > the shadow MMUs.
> >
> > Besides being more intuitive, this enables future simplifications
> > and optimizations because it's not necessary anymore to compute the
> > role outside kvm_init_mmu.  In particular, kvm_mmu_reset_context was not
> > attempting to use a cached PGD to avoid having to figure out the new role.
> > It will soon be able to follow what nested_{vmx,svm}_load_cr3 are doing,
> > and avoid unloading all the cached roots.
> >
> > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> > ---
>
> If you add a sanity check as described in the other thread[*],
>
> Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>

It's not as easy as I thought, but it becomes almost trivial with the 
CPU/MMU role refactoring.  I'll get that posted as soon as I can push a 
final-ish version of this one to kvm/queue.

Paolo