diff -r 5eaec8296a22 xen/arch/x86/hvm/vmx/vmcs.c
--- a/xen/arch/x86/hvm/vmx/vmcs.c	Sun Jul 06 20:16:24 2008 +0100
+++ b/xen/arch/x86/hvm/vmx/vmcs.c	Tue Jul 08 18:08:39 2008 +0800
@@ -89,6 +89,7 @@
 
     min = (CPU_BASED_HLT_EXITING |
            CPU_BASED_INVLPG_EXITING |
+           CPU_BASED_RDTSC_EXITING |
            CPU_BASED_CR3_LOAD_EXITING |
            CPU_BASED_CR3_STORE_EXITING |
            CPU_BASED_MONITOR_EXITING |
diff -r 5eaec8296a22 xen/arch/x86/hvm/vmx/vmx.c
--- a/xen/arch/x86/hvm/vmx/vmx.c	Sun Jul 06 20:16:24 2008 +0100
+++ b/xen/arch/x86/hvm/vmx/vmx.c	Tue Jul 08 18:08:39 2008 +0800
@@ -1374,6 +1374,13 @@
     HVMTRACE_LONG_2D(INVLPG, curr, /*invlpga=*/ 0, TRC_PAR_LONG(vaddr));
     if ( paging_invlpg(curr, vaddr) )
         vpid_sync_vcpu_gva(curr, vaddr);
+}
+
+static void vmx_rdtsc_intercept(struct vcpu *vcpu)
+{
+    uint64_t tsc; 
+    rdtscll(tsc);
+    return;    
 }
 
 #define CASE_SET_REG(REG, reg)      \
@@ -2193,6 +2200,11 @@
         vmx_invlpg_intercept(exit_qualification);
         break;
     }
+    case EXIT_REASON_RDTSC:
+        inst_len = __get_instruction_length();
+        __update_guest_eip(inst_len);
+        vmx_rdtsc_intercept(v);
+        break;
     case EXIT_REASON_VMCALL:
     {
         int rc;