On Fri, May 16, 2025 at 03:46:53PM +0800, Yan Zhao wrote:
> On Wed, May 14, 2025 at 06:56:26AM +0800, Edgecombe, Rick P wrote:
> > On Thu, 2025-04-24 at 11:08 +0800, Yan Zhao wrote:
> > > /*
> > > * If can_yield is true, will release the MMU lock and reschedule if the
> > > * scheduler needs the CPU or there is contention on the MMU lock. If this
> > > @@ -991,6 +1006,8 @@ static bool tdp_mmu_zap_leafs(struct kvm *kvm, struct kvm_mmu_page *root,
> > > !is_last_spte(iter.old_spte, iter.level))
> > > continue;
> > >
> > > + WARN_ON_ONCE(iter_split_required(kvm, root, &iter, start, end));
> > > +
> >
> > Kind of unrelated change? But good idea. Maybe for another patch.
> Yes, will move it to a separate patch in a formal version.
> As initial RFC, I hoped to show related changes in one patch to allow a whole
> picture.
>
> > > +int kvm_tdp_mmu_gfn_range_split_boundary(struct kvm *kvm, struct kvm_gfn_range *range)
> > > +{
> > > + enum kvm_tdp_mmu_root_types types;
> > > + struct kvm_mmu_page *root;
> > > + bool flush = false;
> > > + int ret;
> > > +
> > > + types = kvm_gfn_range_filter_to_root_types(kvm, range->attr_filter) | KVM_INVALID_ROOTS;
> >
> > What is the reason for KVM_INVALID_ROOTS in this case?
> I wanted to keep consistent with that in kvm_tdp_mmu_unmap_gfn_range().
With this consistency, we can warn in tdp_mmu_zap_leafs() as below though
there should be no invalid mirror root.
WARN_ON_ONCE(iter_split_required(kvm, root, &iter, start, end));
