diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index 06d302e..5973410 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -47,7 +47,10 @@
 		__field(int, reason)
 	),
 	TP_fast_assign(
-		strncpy(__entry->name, dev_name(bdi->dev), 32);
+		struct device *dev = bdi->dev;
+		if (!dev)
+			dev = default_backing_dev_info.dev;
+		strncpy(__entry->name, dev_name(dev), 32);
 		__entry->nr_pages = work->nr_pages;
 		__entry->sb_dev = work->sb ? work->sb->s_dev : 0;
 		__entry->sync_mode = work->sync_mode;