KVM: SVM: Trap access to the cr8 register

Later we may be able to use the virtual tpr feature, but for now,
just trap it.

Signed-off-by: Avi Kivity <avi@qumranet.com>

2 files changed, 7 insertions, 2 deletions

diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
index 06beed7d4a08..143d271d4431 100644
--- a/drivers/kvm/svm.c
+++ b/drivers/kvm/svm.c
@@ -449,11 +449,13 @@ static void init_vmcb(struct vmcb *vmcb)
 
         control->intercept_cr_read =    INTERCEPT_CR0_MASK |
                                         INTERCEPT_CR3_MASK |
-                                        INTERCEPT_CR4_MASK;
+                                        INTERCEPT_CR4_MASK |
+                                        INTERCEPT_CR8_MASK;
 
         control->intercept_cr_write =   INTERCEPT_CR0_MASK |
                                         INTERCEPT_CR3_MASK |
-                                        INTERCEPT_CR4_MASK;
+                                        INTERCEPT_CR4_MASK |
+                                        INTERCEPT_CR8_MASK;
 
         control->intercept_dr_read =    INTERCEPT_DR0_MASK |
                                         INTERCEPT_DR1_MASK |
@@ -1195,10 +1197,12 @@ static int (*svm_exit_handlers[])(struct vcpu_svm *svm,
         [SVM_EXIT_READ_CR0]                     = emulate_on_interception,
         [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_WRITE_CR0]                    = emulate_on_interception,
         [SVM_EXIT_WRITE_CR3]                    = emulate_on_interception,
         [SVM_EXIT_WRITE_CR4]                    = emulate_on_interception,
+        [SVM_EXIT_WRITE_CR8]                    = emulate_on_interception,
         [SVM_EXIT_READ_DR0]                     = emulate_on_interception,
         [SVM_EXIT_READ_DR1]                     = emulate_on_interception,
         [SVM_EXIT_READ_DR2]                     = emulate_on_interception,
diff --git a/drivers/kvm/svm.h b/drivers/kvm/svm.h
index 5fa277c0187c..5fd50491b555 100644
--- a/drivers/kvm/svm.h
+++ b/drivers/kvm/svm.h
@@ -204,6 +204,7 @@ struct __attribute__ ((__packed__)) vmcb {
 #define INTERCEPT_CR0_MASK 1
 #define INTERCEPT_CR3_MASK (1 << 3)
 #define INTERCEPT_CR4_MASK (1 << 4)
+#define INTERCEPT_CR8_MASK (1 << 8)
 
 #define INTERCEPT_DR0_MASK 1
 #define INTERCEPT_DR1_MASK (1 << 1)