On Fri, Jul 15, 2011 at 10:46:08AM -0700, K. Y. Srinivasan wrote:

+static bool is_not_null_guid(const __u8 *guid)
+{
+	int i;
+
+	for (i = 0; i < (sizeof(struct hv_vmbus_device_id)); i++)
+		if (guid[i] != 0)
+			return true;
+	return false;
+}

would be nice to add uuid_{le,be}_is_nil helpers to uuid.h.  I also
think simply using a memcpy might be more efficient than the hand-rolled
loop.