diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index c85f11dafd56064c5c77a4e39cd4ad7a74f65755..d1b8e8f97fc2cf563c8396014e68da30c2b603c4 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -48,8 +48,10 @@ struct page {
 						 * inode address_space, or NULL.
 						 * If page mapped as anonymous
 						 * memory, low bit is set, and
-						 * it points to anon_vma object:
-						 * see PAGE_MAPPING_ANON below.
+						 * it points to anon_vma object
+						 * or KSM private structure. See
+						 * PAGE_MAPPING_ANON and
+						 * PAGE_MAPPING_KSM.
 						 */
 		void *s_mem;			/* slab first object */
 		atomic_t compound_mapcount;	/* first tail page */