1 files changed, 47 insertions, 29 deletions

diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 1cbf576852ca..35a05dd2f69c 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -63,10 +63,12 @@
  */
 struct guest_walker {
 	int level;
+	unsigned max_level;
 	gfn_t table_gfn[PT_MAX_FULL_LEVELS];
 	pt_element_t ptes[PT_MAX_FULL_LEVELS];
 	pt_element_t prefetch_ptes[PTE_PREFETCH_NUM];
 	gpa_t pte_gpa[PT_MAX_FULL_LEVELS];
+	pt_element_t __user *ptep_user[PT_MAX_FULL_LEVELS];
 	unsigned pt_access;
 	unsigned pte_access;
 	gfn_t gfn;
@@ -119,6 +121,43 @@ static bool FNAME(is_last_gpte)(struct guest_walker *walker,
 	return false;
 }
 
+static int FNAME(update_accessed_dirty_bits)(struct kvm_vcpu *vcpu,
+					     struct kvm_mmu *mmu,
+					     struct guest_walker *walker,
+					     int write_fault)
+{
+	unsigned level, index;
+	pt_element_t pte, orig_pte;
+	pt_element_t __user *ptep_user;
+	gfn_t table_gfn;
+	int ret;
+
+	for (level = walker->max_level; level >= walker->level; --level) {
+		pte = orig_pte = walker->ptes[level - 1];
+		table_gfn = walker->table_gfn[level - 1];
+		ptep_user = walker->ptep_user[level - 1];
+		index = offset_in_page(ptep_user) / sizeof(pt_element_t);
+		if (!(pte & PT_ACCESSED_MASK)) {
+			trace_kvm_mmu_set_accessed_bit(table_gfn, index, sizeof(pte));
+			pte |= PT_ACCESSED_MASK;
+		}
+		if (level == walker->level && write_fault && !is_dirty_gpte(pte)) {
+			trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte));
+			pte |= PT_DIRTY_MASK;
+		}
+		if (pte == orig_pte)
+			continue;
+
+		ret = FNAME(cmpxchg_gpte)(vcpu, mmu, ptep_user, index, orig_pte, pte);
+		if (ret)
+			return ret;
+
+		mark_page_dirty(vcpu->kvm, table_gfn);
+		walker->ptes[level] = pte;
+	}
+	return 0;
+}
+
 /*
  * Fetch a guest pte for a guest virtual address
  */
@@ -126,6 +165,7 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
 				    struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 				    gva_t addr, u32 access)
 {
+	int ret;
 	pt_element_t pte;
 	pt_element_t __user *uninitialized_var(ptep_user);
 	gfn_t table_gfn;
@@ -153,6 +193,7 @@ retry_walk:
 		--walker->level;
 	}
 #endif
+	walker->max_level = walker->level;
 	ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) ||
 	       (mmu->get_cr3(vcpu) & CR3_NONPAE_RESERVED_BITS) == 0);
 
@@ -183,6 +224,7 @@ retry_walk:
 		ptep_user = (pt_element_t __user *)((void *)host_addr + offset);
 		if (unlikely(__copy_from_user(&pte, ptep_user, sizeof(pte))))
 			goto error;
+		walker->ptep_user[walker->level - 1] = ptep_user;
 
 		trace_kvm_mmu_paging_element(pte, walker->level);
 
@@ -214,21 +256,6 @@ retry_walk:
 					eperm = true;
 		}
 
-		if (!eperm && unlikely(!(pte & PT_ACCESSED_MASK))) {
-			int ret;
-			trace_kvm_mmu_set_accessed_bit(table_gfn, index,
-						       sizeof(pte));
-			ret = FNAME(cmpxchg_gpte)(vcpu, mmu, ptep_user, index,
-						  pte, pte|PT_ACCESSED_MASK);
-			if (unlikely(ret < 0))
-				goto error;
-			else if (ret)
-				goto retry_walk;
-
-			mark_page_dirty(vcpu->kvm, table_gfn);
-			pte |= PT_ACCESSED_MASK;
-		}
-
 		walker->ptes[walker->level - 1] = pte;
 
 		if (last_gpte) {
@@ -268,21 +295,12 @@ retry_walk:
 
 	if (!write_fault)
 		protect_clean_gpte(&pte_access, pte);
-	else if (unlikely(!is_dirty_gpte(pte))) {
-		int ret;
 
-		trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte));
-		ret = FNAME(cmpxchg_gpte)(vcpu, mmu, ptep_user, index,
-					  pte, pte|PT_DIRTY_MASK);
-		if (unlikely(ret < 0))
-			goto error;
-		else if (ret)
-			goto retry_walk;
-
-		mark_page_dirty(vcpu->kvm, table_gfn);
-		pte |= PT_DIRTY_MASK;
-		walker->ptes[walker->level - 1] = pte;
-	}
+	ret = FNAME(update_accessed_dirty_bits)(vcpu, mmu, walker, write_fault);
+	if (unlikely(ret < 0))
+		goto error;
+	else if (ret)
+		goto retry_walk;
 
 	walker->pt_access = pt_access;
 	walker->pte_access = pte_access;