diff --git a/arch/i386/xen/enlighten.c b/arch/i386/xen/enlighten.c
index f0c3751..f01bfcd 100644
--- a/arch/i386/xen/enlighten.c
+++ b/arch/i386/xen/enlighten.c
@@ -623,8 +623,8 @@
 
 static void xen_write_cr4(unsigned long cr4)
 {
-	/* never allow TSC to be disabled */
-	native_write_cr4(cr4 & ~X86_CR4_TSD);
+	/* Just ignore cr4 changes; Xen doesn't allow us to do
+	   anything anyway. */
 }
 
 static unsigned long xen_read_cr3(void)