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Diffstat (limited to 'arch/x86/kvm/mmu.c')
-rw-r--r--arch/x86/kvm/mmu.c28
1 files changed, 18 insertions, 10 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 5269aa057dfa..bac8d228d82b 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -83,7 +83,16 @@ module_param(dbg, bool, 0644);
#define PTE_PREFETCH_NUM 8
#define PT_FIRST_AVAIL_BITS_SHIFT 10
-#define PT64_SECOND_AVAIL_BITS_SHIFT 52
+#define PT64_SECOND_AVAIL_BITS_SHIFT 54
+
+/*
+ * The mask used to denote special SPTEs, which can be either MMIO SPTEs or
+ * Access Tracking SPTEs.
+ */
+#define SPTE_SPECIAL_MASK (3ULL << 52)
+#define SPTE_AD_ENABLED_MASK (0ULL << 52)
+#define SPTE_AD_DISABLED_MASK (1ULL << 52)
+#define SPTE_MMIO_MASK (3ULL << 52)
#define PT64_LEVEL_BITS 9
@@ -219,12 +228,11 @@ static u64 __read_mostly shadow_present_mask;
static u64 __read_mostly shadow_me_mask;
/*
- * SPTEs used by MMUs without A/D bits are marked with shadow_acc_track_value.
- * Non-present SPTEs with shadow_acc_track_value set are in place for access
- * tracking.
+ * SPTEs used by MMUs without A/D bits are marked with SPTE_AD_DISABLED_MASK;
+ * shadow_acc_track_mask is the set of bits to be cleared in non-accessed
+ * pages.
*/
static u64 __read_mostly shadow_acc_track_mask;
-static const u64 shadow_acc_track_value = SPTE_SPECIAL_MASK;
/*
* The mask/shift to use for saving the original R/X bits when marking the PTE
@@ -304,7 +312,7 @@ void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask, u64 mmio_value, u64 access_mask)
{
BUG_ON((u64)(unsigned)access_mask != access_mask);
BUG_ON((mmio_mask & mmio_value) != mmio_value);
- shadow_mmio_value = mmio_value | SPTE_SPECIAL_MASK;
+ shadow_mmio_value = mmio_value | SPTE_MMIO_MASK;
shadow_mmio_mask = mmio_mask | SPTE_SPECIAL_MASK;
shadow_mmio_access_mask = access_mask;
}
@@ -323,7 +331,7 @@ static inline bool sp_ad_disabled(struct kvm_mmu_page *sp)
static inline bool spte_ad_enabled(u64 spte)
{
MMU_WARN_ON(is_mmio_spte(spte));
- return !(spte & shadow_acc_track_value);
+ return (spte & SPTE_SPECIAL_MASK) == SPTE_AD_ENABLED_MASK;
}
static inline u64 spte_shadow_accessed_mask(u64 spte)
@@ -461,7 +469,7 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
{
BUG_ON(!dirty_mask != !accessed_mask);
BUG_ON(!accessed_mask && !acc_track_mask);
- BUG_ON(acc_track_mask & shadow_acc_track_value);
+ BUG_ON(acc_track_mask & SPTE_SPECIAL_MASK);
shadow_user_mask = user_mask;
shadow_accessed_mask = accessed_mask;
@@ -2622,7 +2630,7 @@ static void link_shadow_page(struct kvm_vcpu *vcpu, u64 *sptep,
shadow_user_mask | shadow_x_mask | shadow_me_mask;
if (sp_ad_disabled(sp))
- spte |= shadow_acc_track_value;
+ spte |= SPTE_AD_DISABLED_MASK;
else
spte |= shadow_accessed_mask;
@@ -2968,7 +2976,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
sp = page_header(__pa(sptep));
if (sp_ad_disabled(sp))
- spte |= shadow_acc_track_value;
+ spte |= SPTE_AD_DISABLED_MASK;
/*
* For the EPT case, shadow_present_mask is 0 if hardware