On Mon, Mar 28, 2022, Vitaly Kuznetsov wrote: > Sean Christopherson <seanjc@xxxxxxxxxx> writes: > > > Re-introduce zapping only leaf SPTEs in kvm_zap_gfn_range() and > > kvm_tdp_mmu_unmap_gfn_range(), this time without losing a pending TLB > > flush when processing multiple roots (including nested TDP shadow roots). > > Dropping the TLB flush resulted in random crashes when running Hyper-V > > Server 2019 in a guest with KSM enabled in the host (or any source of > > mmu_notifier invalidations, KSM is just the easiest to force). > > > > This effectively revert commits 873dd122172f8cce329113cfb0dfe3d2344d80c0 > > and fcb93eb6d09dd302cbef22bd95a5858af75e4156, and thus restores commit > > cf3e26427c08ad9015956293ab389004ac6a338e, plus this delta on top: > > > > bool kvm_tdp_mmu_zap_leafs(struct kvm *kvm, int as_id, gfn_t start, gfn_t end, > > struct kvm_mmu_page *root; > > > > for_each_tdp_mmu_root_yield_safe(kvm, root, as_id) > > - flush = tdp_mmu_zap_leafs(kvm, root, start, end, can_yield, false); > > + flush = tdp_mmu_zap_leafs(kvm, root, start, end, can_yield, flush); > > > > return flush; > > } > > > > I confirm this fixes the issue I was seeing, thanks! > > Tested-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> Phew! I think I would have cried were that not the case :-) Thanks for testing!
