---

yaml --- r: 356836 b: refs/heads/master c: c228850 h: refs/heads/master v: v3
git-mirror · Jan 10, 2013 · be6417d · be6417d
1 parent d608803
commit be6417d
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Showing 3 changed files with 39 additions and 40 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b26ba22bb4f12289f9d5eb878c490e674934a197
+refs/heads/master: c22885050e651c2f5d2a1706cdc2eb38698db968
diff --git a/trunk/arch/x86/kvm/mmu.c b/trunk/arch/x86/kvm/mmu.c
@@ -2342,8 +2342,7 @@ static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn,
 }
 
 static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
-		    unsigned pte_access, int user_fault,
-		    int write_fault, int level,
+		    unsigned pte_access, int level,
 		    gfn_t gfn, pfn_t pfn, bool speculative,
 		    bool can_unsync, bool host_writable)
 {
@@ -2378,9 +2377,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 
 	spte |= (u64)pfn << PAGE_SHIFT;
 
-	if ((pte_access & ACC_WRITE_MASK)
-	    || (!vcpu->arch.mmu.direct_map && write_fault
-		&& !is_write_protection(vcpu) && !user_fault)) {
+	if (pte_access & ACC_WRITE_MASK) {
 
 		/*
 		 * There are two cases:
@@ -2399,19 +2396,6 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 
 		spte |= PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE;
 
-		if (!vcpu->arch.mmu.direct_map
-		    && !(pte_access & ACC_WRITE_MASK)) {
-			spte &= ~PT_USER_MASK;
-			/*
-			 * If we converted a user page to a kernel page,
-			 * so that the kernel can write to it when cr0.wp=0,
-			 * then we should prevent the kernel from executing it
-			 * if SMEP is enabled.
-			 */
-			if (kvm_read_cr4_bits(vcpu, X86_CR4_SMEP))
-				spte |= PT64_NX_MASK;
-		}
-
 		/*
 		 * Optimization: for pte sync, if spte was writable the hash
 		 * lookup is unnecessary (and expensive). Write protection
@@ -2442,18 +2426,15 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 
 static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 			 unsigned pt_access, unsigned pte_access,
-			 int user_fault, int write_fault,
-			 int *emulate, int level, gfn_t gfn,
-			 pfn_t pfn, bool speculative,
-			 bool host_writable)
+			 int write_fault, int *emulate, int level, gfn_t gfn,
+			 pfn_t pfn, bool speculative, bool host_writable)
 {
 	int was_rmapped = 0;
 	int rmap_count;
 
-	pgprintk("%s: spte %llx access %x write_fault %d"
-		 " user_fault %d gfn %llx\n",
+	pgprintk("%s: spte %llx access %x write_fault %d gfn %llx\n",
 		 __func__, *sptep, pt_access,
-		 write_fault, user_fault, gfn);
+		 write_fault, gfn);
 
 	if (is_rmap_spte(*sptep)) {
 		/*
@@ -2477,9 +2458,8 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 			was_rmapped = 1;
 	}
 
-	if (set_spte(vcpu, sptep, pte_access, user_fault, write_fault,
-		      level, gfn, pfn, speculative, true,
-		      host_writable)) {
+	if (set_spte(vcpu, sptep, pte_access, level, gfn, pfn, speculative,
+	      true, host_writable)) {
 		if (write_fault)
 			*emulate = 1;
 		kvm_mmu_flush_tlb(vcpu);
@@ -2571,10 +2551,9 @@ static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu,
 		return -1;
 
 	for (i = 0; i < ret; i++, gfn++, start++)
-		mmu_set_spte(vcpu, start, ACC_ALL,
-			     access, 0, 0, NULL,
-			     sp->role.level, gfn,
-			     page_to_pfn(pages[i]), true, true);
+		mmu_set_spte(vcpu, start, ACC_ALL, access, 0, NULL,
+			     sp->role.level, gfn, page_to_pfn(pages[i]),
+			     true, true);
 
 	return 0;
 }
@@ -2636,8 +2615,8 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
 			unsigned pte_access = ACC_ALL;
 
 			mmu_set_spte(vcpu, iterator.sptep, ACC_ALL, pte_access,
-				     0, write, &emulate,
-				     level, gfn, pfn, prefault, map_writable);
+				     write, &emulate, level, gfn, pfn,
+				     prefault, map_writable);
 			direct_pte_prefetch(vcpu, iterator.sptep);
 			++vcpu->stat.pf_fixed;
 			break;

diff --git a/trunk/arch/x86/kvm/paging_tmpl.h b/trunk/arch/x86/kvm/paging_tmpl.h
@@ -326,7 +326,7 @@ FNAME(prefetch_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
 	 * we call mmu_set_spte() with host_writable = true because
 	 * pte_prefetch_gfn_to_pfn always gets a writable pfn.
 	 */
-	mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0,
+	mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0,
 		     NULL, PT_PAGE_TABLE_LEVEL, gfn, pfn, true, true);
 
 	return true;
@@ -401,7 +401,7 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw,
  */
 static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 			 struct guest_walker *gw,
-			 int user_fault, int write_fault, int hlevel,
+			 int write_fault, int hlevel,
 			 pfn_t pfn, bool map_writable, bool prefault)
 {
 	struct kvm_mmu_page *sp = NULL;
@@ -474,7 +474,7 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 
 	clear_sp_write_flooding_count(it.sptep);
 	mmu_set_spte(vcpu, it.sptep, access, gw->pte_access,
-		     user_fault, write_fault, &emulate, it.level,
+		     write_fault, &emulate, it.level,
 		     gw->gfn, pfn, prefault, map_writable);
 	FNAME(pte_prefetch)(vcpu, gw, it.sptep);
 
@@ -560,6 +560,26 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 				walker.gfn, pfn, walker.pte_access, &r))
 		return r;
 
+	/*
+	 * Do not change pte_access if the pfn is a mmio page, otherwise
+	 * we will cache the incorrect access into mmio spte.
+	 */
+	if (write_fault && !(walker.pte_access & ACC_WRITE_MASK) &&
+	     !is_write_protection(vcpu) && !user_fault &&
+	      !is_noslot_pfn(pfn)) {
+		walker.pte_access |= ACC_WRITE_MASK;
+		walker.pte_access &= ~ACC_USER_MASK;
+
+		/*
+		 * If we converted a user page to a kernel page,
+		 * so that the kernel can write to it when cr0.wp=0,
+		 * then we should prevent the kernel from executing it
+		 * if SMEP is enabled.
+		 */
+		if (kvm_read_cr4_bits(vcpu, X86_CR4_SMEP))
+			walker.pte_access &= ~ACC_EXEC_MASK;
+	}
+
 	spin_lock(&vcpu->kvm->mmu_lock);
 	if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
 		goto out_unlock;
@@ -568,7 +588,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 	kvm_mmu_free_some_pages(vcpu);
 	if (!force_pt_level)
 		transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level);
-	r = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
+	r = FNAME(fetch)(vcpu, addr, &walker, write_fault,
 			 level, pfn, map_writable, prefault);
 	++vcpu->stat.pf_fixed;
 	kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT);
@@ -743,7 +763,7 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 
 		host_writable = sp->spt[i] & SPTE_HOST_WRITEABLE;
 
-		set_spte(vcpu, &sp->spt[i], pte_access, 0, 0,
+		set_spte(vcpu, &sp->spt[i], pte_access,
 			 PT_PAGE_TABLE_LEVEL, gfn,
 			 spte_to_pfn(sp->spt[i]), true, false,
 			 host_writable);