On Fri, Jun 30, 2023 at 08:37:06AM -0700, Sean Christopherson wrote: > On Fri, Jun 30, 2023, Yuan Yao wrote: > > On Thu, Jun 29, 2023 at 01:30:31PM -0700, Sean Christopherson wrote: > > > @@ -3834,8 +3822,8 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) > > > if (!(pdptrs[i] & PT_PRESENT_MASK)) > > > continue; > > > > > > - if (mmu_check_root(vcpu, pdptrs[i] >> PAGE_SHIFT)) > > > - return 1; > > > + if (kvm_vcpu_is_visible_gfn(vcpu, pdptrs[i] >> PAGE_SHIFT)) > > > + pdptrs[i] = 0; > > > > Hi Sean, > > > > Should this be "!kvm_vcpu_is_visible_gfn(vcpu, pdptrs[i] >> PAGE_SHIFT)" and > > Yep, typo that inverted the check. Thanks for saving me some debug time! > > > turn the pae_root[i] to dummy root yet ? > > No, zeroing the PDPTR is sufficient. Unlike CR3, which is always "present", PDPTRs > have a present bit and so KVM can communicate to hardware that the entry isn't > valid simply by clearing the PDPTPR. Got it, same as how KVM deal with other middle level entries, thanks for the explanation!
