[26/39] KVM: SVM: Selective cr0 intercept

Commit Message

Avi Kivity Feb. 13, 2010, 8:01 a.m. UTC

None

Patch

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 27273ed..83c7ab1 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -571,6 +571,7 @@  static void init_vmcb(struct vcpu_svm *svm)
 	control->intercept = 	(1ULL << INTERCEPT_INTR) |
 				(1ULL << INTERCEPT_NMI) |
 				(1ULL << INTERCEPT_SMI) |
+				(1ULL << INTERCEPT_SELECTIVE_CR0) |
 				(1ULL << INTERCEPT_CPUID) |
 				(1ULL << INTERCEPT_INVD) |
 				(1ULL << INTERCEPT_HLT) |
@@ -963,6 +964,27 @@  static void svm_decache_cr4_guest_bits(struct kvm_vcpu *vcpu)
 {
 }
 
+static void update_cr0_intercept(struct vcpu_svm *svm)
+{
+	ulong gcr0 = svm->vcpu.arch.cr0;
+	u64 *hcr0 = &svm->vmcb->save.cr0;
+
+	if (!svm->vcpu.fpu_active)
+		*hcr0 |= SVM_CR0_SELECTIVE_MASK;
+	else
+		*hcr0 = (*hcr0 & ~SVM_CR0_SELECTIVE_MASK)
+			| (gcr0 & SVM_CR0_SELECTIVE_MASK);
+
+
+	if (gcr0 == *hcr0 && svm->vcpu.fpu_active) {
+		svm->vmcb->control.intercept_cr_read &= ~INTERCEPT_CR0_MASK;
+		svm->vmcb->control.intercept_cr_write &= ~INTERCEPT_CR0_MASK;
+	} else {
+		svm->vmcb->control.intercept_cr_read |= INTERCEPT_CR0_MASK;
+		svm->vmcb->control.intercept_cr_write |= INTERCEPT_CR0_MASK;
+	}
+}
+
 static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -994,6 +1016,7 @@  static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
 	 */
 	cr0 &= ~(X86_CR0_CD | X86_CR0_NW);
 	svm->vmcb->save.cr0 = cr0;
+	update_cr0_intercept(svm);
 }
 
 static void svm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
@@ -1239,11 +1262,8 @@  static int ud_interception(struct vcpu_svm *svm)
 static int nm_interception(struct vcpu_svm *svm)
 {
 	svm->vmcb->control.intercept_exceptions &= ~(1 << NM_VECTOR);
-	if (!kvm_read_cr0_bits(&svm->vcpu, X86_CR0_TS))
-		svm->vmcb->save.cr0 &= ~X86_CR0_TS;
-	else
-		svm->vmcb->save.cr0 |= X86_CR0_TS;
 	svm->vcpu.fpu_active = 1;
+	update_cr0_intercept(svm);
 
 	return 1;
 }
@@ -2296,7 +2316,7 @@  static int (*svm_exit_handlers[])(struct vcpu_svm *svm) = {
 	[SVM_EXIT_READ_CR3]           		= emulate_on_interception,
 	[SVM_EXIT_READ_CR4]           		= emulate_on_interception,
 	[SVM_EXIT_READ_CR8]           		= emulate_on_interception,
-	/* for now: */
+	[SVM_EXIT_CR0_SEL_WRITE]		= emulate_on_interception,
 	[SVM_EXIT_WRITE_CR0]          		= emulate_on_interception,
 	[SVM_EXIT_WRITE_CR3]          		= emulate_on_interception,
 	[SVM_EXIT_WRITE_CR4]          		= emulate_on_interception,
@@ -2914,8 +2934,8 @@  static void svm_fpu_deactivate(struct kvm_vcpu *vcpu)
 		return;
 	}
 
+	update_cr0_intercept(svm);
 	svm->vmcb->control.intercept_exceptions |= 1 << NM_VECTOR;
-	svm->vmcb->save.cr0 |= X86_CR0_TS;
 }
 
 static struct kvm_x86_ops svm_x86_ops = {