KVM: VMX: Use EPT Access bit in response to memory notifiers

Signed-off-by: Haitao Shan <haitao.shan@intel.com>
Signed-off-by: Xudong Hao <xudong.hao@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

2 files changed, 12 insertions, 8 deletions

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index be3cea4407ff..d07e436b7a42 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1242,7 +1242,8 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
         int young = 0;
 
         /*
-         * Emulate the accessed bit for EPT, by checking if this page has
+         * In case of absence of EPT Access and Dirty Bits supports,
+         * emulate the accessed bit for EPT, by checking if this page has
          * an EPT mapping, and clearing it if it does. On the next access,
          * a new EPT mapping will be established.
          * This has some overhead, but not as much as the cost of swapping
@@ -1253,11 +1254,12 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
 
         for (sptep = rmap_get_first(*rmapp, &iter); sptep;
              sptep = rmap_get_next(&iter)) {
-                BUG_ON(!(*sptep & PT_PRESENT_MASK));
+                BUG_ON(!is_shadow_present_pte(*sptep));
 
-                if (*sptep & PT_ACCESSED_MASK) {
+                if (*sptep & shadow_accessed_mask) {
                         young = 1;
-                        clear_bit(PT_ACCESSED_SHIFT, (unsigned long *)sptep);
+                        clear_bit((ffs(shadow_accessed_mask) - 1),
+                                 (unsigned long *)sptep);
                 }
         }
 
@@ -1281,9 +1283,9 @@ static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
 
         for (sptep = rmap_get_first(*rmapp, &iter); sptep;
              sptep = rmap_get_next(&iter)) {
-                BUG_ON(!(*sptep & PT_PRESENT_MASK));
+                BUG_ON(!is_shadow_present_pte(*sptep));
 
-                if (*sptep & PT_ACCESSED_MASK) {
+                if (*sptep & shadow_accessed_mask) {
                         young = 1;
                         break;
                 }
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index d392e5427ca0..396148ab089b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -7289,8 +7289,10 @@ static int __init vmx_init(void)
         vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_EIP, false);
 
         if (enable_ept) {
-                kvm_mmu_set_mask_ptes(0ull, 0ull, 0ull, 0ull,
-                                VMX_EPT_EXECUTABLE_MASK);
+                kvm_mmu_set_mask_ptes(0ull,
+                        (enable_ept_ad_bits) ? VMX_EPT_ACCESS_BIT : 0ull,
+                        (enable_ept_ad_bits) ? VMX_EPT_DIRTY_BIT : 0ull,
+                        0ull, VMX_EPT_EXECUTABLE_MASK);
                 ept_set_mmio_spte_mask();
                 kvm_enable_tdp();
         } else