KVM: MMU: do not update slot bitmap if spte is nonpresent

Set slot bitmap only if the spte is present

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 7 insertions, 8 deletions

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 03323dc705c2..02c839f40e29 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -743,9 +743,6 @@ static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
         struct kvm_mmu_page *sp;
         unsigned long *rmapp;
 
-        if (!is_rmap_spte(*spte))
-                return 0;
-
         sp = page_header(__pa(spte));
         kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn);
         rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level);
@@ -2087,11 +2084,13 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
         if (!was_rmapped && is_large_pte(*sptep))
                 ++vcpu->kvm->stat.lpages;
 
-        page_header_update_slot(vcpu->kvm, sptep, gfn);
-        if (!was_rmapped) {
-                rmap_count = rmap_add(vcpu, sptep, gfn);
-                if (rmap_count > RMAP_RECYCLE_THRESHOLD)
-                        rmap_recycle(vcpu, sptep, gfn);
+        if (is_shadow_present_pte(*sptep)) {
+                page_header_update_slot(vcpu->kvm, sptep, gfn);
+                if (!was_rmapped) {
+                        rmap_count = rmap_add(vcpu, sptep, gfn);
+                        if (rmap_count > RMAP_RECYCLE_THRESHOLD)
+                                rmap_recycle(vcpu, sptep, gfn);
+                }
         }
         kvm_release_pfn_clean(pfn);
         if (speculative) {