On Thu, May 30, 2024 at 11:07 PM Rick Edgecombe
<rick.p.edgecombe@xxxxxxxxx> wrote:
>
> From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
>
> When invalidating roots, respect the root type passed.
>
> kvm_tdp_mmu_invalidate_roots() is called with different root types. For
> kvm_mmu_zap_all_fast() it only operates on shared roots. But when tearing
> down a VM it needs to invalidate all roots. Check the root type in root
> iterator.
This patch and patch 12 are small enough that they can be merged.
> @@ -1135,6 +1135,7 @@ void kvm_tdp_mmu_zap_invalidated_roots(struct kvm *kvm)
> void kvm_tdp_mmu_invalidate_roots(struct kvm *kvm,
> enum kvm_process process_types)
> {
> + enum kvm_tdp_mmu_root_types root_types = kvm_process_to_root_types(kvm, process_types);
Maybe pass directly enum kvm_tdp_mmu_root_types?
Looking at patch 12:
+ /*
+ * The private page tables doesn't support fast zapping. The
+ * caller should handle it by other way.
+ */
+ kvm_tdp_mmu_invalidate_roots(kvm, KVM_PROCESS_SHARED);
now that we have separated private-ness and external-ness, it sounds
much better to write:
/*
* External page tables don't support fast zapping, therefore
* their mirrors must be invalidated separately by the caller.
*/
kvm_tdp_mmu_invalidate_roots(kvm, KVM_DIRECT_ROOTS);
while kvm_mmu_uninit_tdp_mmu() can pass KVM_ANY_ROOTS. It may also be
worth adding an
if (WARN_ON_ONCE(root_types & KVM_INVALID_ROOTS))
root_types &= ~KVM_INVALID_ROOTS;
to document the invariants.
Paolo
