1 files changed, 15 insertions, 1 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 668bbfee0cce..4466feb4c69b 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -987,7 +987,16 @@ static void xen_write_cr4(unsigned long cr4)
 
         native_write_cr4(cr4);
 }
-
+#ifdef CONFIG_X86_64
+static inline unsigned long xen_read_cr8(void)
+{
+        return 0;
+}
+static inline void xen_write_cr8(unsigned long val)
+{
+        BUG_ON(val);
+}
+#endif
 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
 {
         int ret;
@@ -1156,6 +1165,11 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = {
         .read_cr4_safe = native_read_cr4_safe,
         .write_cr4 = xen_write_cr4,
 
+#ifdef CONFIG_X86_64
+        .read_cr8 = xen_read_cr8,
+        .write_cr8 = xen_write_cr8,
+#endif
+
         .wbinvd = native_wbinvd,
 
         .read_msr = native_read_msr_safe,