KVM: VMX: fix tlb flush with invalid root

Commit Message

Xiao Guangrong July 3, 2010, 8:02 a.m. UTC

None

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 2bda624..8f522ec 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -40,6 +40,8 @@ 
 				  0xFFFFFF0000000000ULL)
 
 #define INVALID_PAGE (~(hpa_t)0)
+#define VALID_PAGE(x) ((x) != INVALID_PAGE)
+
 #define UNMAPPED_GVA (~(gpa_t)0)
 
 /* KVM Hugepage definitions for x86 */
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a0c5c31..399ddb0 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -92,8 +92,6 @@  module_param(oos_shadow, bool, 0644);
 #define PT_FIRST_AVAIL_BITS_SHIFT 9
 #define PT64_SECOND_AVAIL_BITS_SHIFT 52
 
-#define VALID_PAGE(x) ((x) != INVALID_PAGE)
-
 #define PT64_LEVEL_BITS 9
 
 #define PT64_LEVEL_SHIFT(level) \
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 806ab12..ebaaeaf 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1831,8 +1831,11 @@  static void exit_lmode(struct kvm_vcpu *vcpu)
 static void vmx_flush_tlb(struct kvm_vcpu *vcpu)
 {
 	vpid_sync_context(to_vmx(vcpu));
-	if (enable_ept)
+	if (enable_ept) {
+		if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
+			return;
 		ept_sync_context(construct_eptp(vcpu->arch.mmu.root_hpa));
+	}
 }
 
 static void vmx_decache_cr0_guest_bits(struct kvm_vcpu *vcpu)