diff --git a/include/linux/kobject.h b/include/linux/kobject.h
index 637f67002c5a..e6284591599e 100644
--- a/include/linux/kobject.h
+++ b/include/linux/kobject.h
@@ -66,7 +66,7 @@ struct kobject {
 	struct kobject		*parent;
 	struct kset		*kset;
 	struct kobj_type	*ktype;
-	struct kernfs_node	*sd;
+	struct kernfs_node	*sd; /* sysfs directory entry */
 	struct kref		kref;
 #ifdef CONFIG_DEBUG_KOBJECT_RELEASE
 	struct delayed_work	release;