diff --git a/include/linux/mmiotrace.h b/include/linux/mmiotrace.h
index 5cbbc37..61d19e1 100644
--- a/include/linux/mmiotrace.h
+++ b/include/linux/mmiotrace.h
@@ -18,7 +18,7 @@
 	unsigned long len; /* length of the probe region */
 	kmmio_pre_handler_t pre_handler; /* Called before addr is executed. */
 	kmmio_post_handler_t post_handler; /* Called after addr is executed */
-	void *user_data;
+	void *private;
 };
 
 /* kmmio is active by some kmmio_probes? */