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

From: Sean Christopherson
Date: Fri Feb 11 2022 - 12:45:55 EST


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>


[*] https://lore.kernel.org/all/1e8c38eb-d66a-60e7-9432-eb70e7ec1dd4@xxxxxxxxxx