Skip setting SPTEs if no change is expected. Reviewed-by: Peter Feiner <pfeiner@xxxxxxxxxx> Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx> --- arch/x86/kvm/mmu/tdp_mmu.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 1987da0da66e..2650fa9fe066 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -882,6 +882,9 @@ static bool wrprot_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, !is_last_spte(iter.old_spte, iter.level)) continue; + if (!(iter.old_spte & PT_WRITABLE_MASK)) + continue; + new_spte = iter.old_spte & ~PT_WRITABLE_MASK; tdp_mmu_set_spte_no_dirty_log(kvm, &iter, new_spte); @@ -1079,6 +1082,9 @@ static bool set_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, if (!is_shadow_present_pte(iter.old_spte)) continue; + if (iter.old_spte & shadow_dirty_mask) + continue; + new_spte = iter.old_spte | shadow_dirty_mask; tdp_mmu_set_spte(kvm, &iter, new_spte); -- 2.30.0.284.gd98b1dd5eaa7-goog
