diff -r ad5960696d68 xen/arch/x86/hvm/nestedhvm.c
--- a/xen/arch/x86/hvm/nestedhvm.c	Fri Apr 15 12:00:13 2011 +0200
+++ b/xen/arch/x86/hvm/nestedhvm.c	Fri Apr 15 15:43:15 2011 +0200
@@ -61,7 +61,7 @@ nestedhvm_vcpu_reset(struct vcpu *v)
     nv->nv_vvmcxaddr = VMCX_EADDR;
     nv->nv_flushp2m = 0;
     nv->nv_p2m = NULL;
+    hvm_asid_flush_vcpu_asid(&nv->nv_n2asid);
 
     if ( hvm_funcs.nhvm_vcpu_reset )
         hvm_funcs.nhvm_vcpu_reset(v);
diff -r ad5960696d68 xen/arch/x86/hvm/svm/asid.c
--- a/xen/arch/x86/hvm/svm/asid.c	Fri Apr 15 12:00:13 2011 +0200
+++ b/xen/arch/x86/hvm/svm/asid.c	Fri Apr 15 15:43:15 2011 +0200
@@ -43,10 +43,16 @@ asmlinkage void svm_asid_handle_vmrun(vo
 {
     struct vcpu *curr = current;
     struct vmcb_struct *vmcb = curr->arch.hvm_svm.vmcb;
-    struct hvm_vcpu_asid *p_asid =
-        nestedhvm_vcpu_in_guestmode(curr)
-        ? &vcpu_nestedhvm(curr).nv_n2asid : &curr->arch.hvm_vcpu.n1asid;
-    bool_t need_flush = hvm_asid_handle_vmenter(p_asid);
+    struct hvm_vcpu_asid *p_asid;
+    bool_t need_flush;
+    bool_t vcpu_guestmode = 0;
+
+    if (nestedhvm_enabled(curr->domain) && nestedhvm_vcpu_in_guestmode(curr))
+        vcpu_guestmode = 1;
+
+    p_asid = vcpu_guestmode ?
+        &vcpu_nestedhvm(curr).nv_n2asid : &curr->arch.hvm_vcpu.n1asid;
+    need_flush = hvm_asid_handle_vmenter(p_asid);
 
     /* ASID 0 indicates that ASIDs are disabled. */
     if ( p_asid->asid == 0 )