diff -r 2007b3ab2f11 tools/libxc/xc_cpuid_x86.c
--- a/tools/libxc/xc_cpuid_x86.c	Wed Jun 01 15:23:04 2011 +0200
+++ b/tools/libxc/xc_cpuid_x86.c	Fri Jun 03 16:54:05 2011 +0200
@@ -153,7 +153,8 @@ static void amd_xc_cpuid_policy(
          * available in hw and which are implemented
          */
         regs[3] &= (SVM_FEATURE_NPT | SVM_FEATURE_LBRV | \
-            SVM_FEATURE_NRIPS | SVM_FEATURE_PAUSEFILTER);
+            SVM_FEATURE_NRIPS | SVM_FEATURE_PAUSEFILTER | \
+            SVM_FEATURE_DECODEASSISTS);
 
         /* Pass 2: Always enable SVM features which are emulated */
         regs[3] |= SVM_FEATURE_VMCBCLEAN;
diff -r 2007b3ab2f11 xen/arch/x86/hvm/svm/nestedsvm.c
--- a/xen/arch/x86/hvm/svm/nestedsvm.c	Wed Jun 01 15:23:04 2011 +0200
+++ b/xen/arch/x86/hvm/svm/nestedsvm.c	Fri Jun 03 16:54:05 2011 +0200
@@ -1056,6 +1056,10 @@ nsvm_vmcb_prepare4vmexit(struct vcpu *v)
     /* NextRIP */
     ns_vmcb->nextrip = n2vmcb->nextrip;
 
+    /* Decode Assist */
+    ns_vmcb->guest_ins_len = n2vmcb->guest_ins_len;
+    memcpy(ns_vmcb->guest_ins, n2vmcb->guest_ins, sizeof(ns_vmcb->guest_ins));
+
     /*
      * VMCB Save State Area
      */