diff -r 5ad2a1476b3c -r 1dfbe5675b7a drivers/xen/tpmback/xenbus.c
--- a/drivers/xen/tpmback/xenbus.c	Mon Jun 07 13:54:21 2010 -0400
+++ b/drivers/xen/tpmback/xenbus.c	Wed Jul 07 13:38:42 2010 -0400
@@ -52,6 +52,18 @@
 	return res;
 }
 
+static void tpmback_disconnect(struct xenbus_device *dev) {
+	struct backend_info *be = dev->dev.driver_data;
+
+	if (be->tpmif) {
+		be->tpmif->bi = NULL;
+		vtpm_release_packets(be->tpmif, 0);
+		tpmif_put(be->tpmif);
+		be->tpmif = NULL;
+	}
+	return;
+}
+
 static int tpmback_remove(struct xenbus_device *dev)
 {
 	struct backend_info *be = dev->dev.driver_data;
@@ -63,12 +75,7 @@
 		kfree(be->backend_watch.node);
 		be->backend_watch.node = NULL;
 	}
-	if (be->tpmif) {
-		be->tpmif->bi = NULL;
-		vtpm_release_packets(be->tpmif, 0);
-		tpmif_put(be->tpmif);
-		be->tpmif = NULL;
-	}
+	tpmback_disconnect(dev);
 	kfree(be);
 	dev->dev.driver_data = NULL;
 	return 0;
@@ -162,6 +169,7 @@
 
 	case XenbusStateUnknown: /* keep it here */
 	case XenbusStateClosed:
+		tpmback_disconnect(dev); /*Unmap shared pages first */
 		xenbus_switch_state(dev, XenbusStateClosed);
 		device_unregister(&be->dev->dev);
 		tpmback_remove(dev);
@@ -213,9 +221,10 @@
 	if (err)
 		xenbus_dev_fatal(be->dev, err, "end of transaction");
 
+	be->tpmif->status = CONNECTED;
 	err = xenbus_switch_state(dev, XenbusStateConnected);
-	if (!err)
-		be->tpmif->status = CONNECTED;
+	if (err)
+		be->tpmif->status = DISCONNECTED;
 	return;
 abort:
 	xenbus_transaction_end(xbt, 1);