diff --git a/mm/ksm.c b/mm/ksm.c
index caa54a5..614b2cc 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1469,8 +1469,22 @@
 	tree_rmap_item =
 		unstable_tree_search_insert(rmap_item, page, &tree_page);
 	if (tree_rmap_item) {
+		bool split;
+
 		kpage = try_to_merge_two_pages(rmap_item, page,
 						tree_rmap_item, tree_page);
+		/*
+		 * If both pages we tried to merge belong to the same compound
+		 * page, then we actually ended up increasing the reference
+		 * count of the same compound page twice, and split_huge_page
+		 * failed.
+		 * Here we set a flag if that happened, and we use it later to
+		 * try split_huge_page again. Since we call put_page right
+		 * afterwards, the reference count will be correct and
+		 * split_huge_page should succeed.
+		 */
+		split = PageTransCompound(page)
+			&& compound_head(page) == compound_head(tree_page);
 		put_page(tree_page);
 		if (kpage) {
 			/*
@@ -1495,6 +1509,20 @@
 				break_cow(tree_rmap_item);
 				break_cow(rmap_item);
 			}
+		} else if (split) {
+			/*
+			 * We are here if we tried to merge two pages and
+			 * failed because they both belonged to the same
+			 * compound page. We will split the page now, but no
+			 * merging will take place.
+			 * We do not want to add the cost of a full lock; if
+			 * the page is locked, it is better to skip it and
+			 * perhaps try again later.
+			 */
+			if (!trylock_page(page))
+				return;
+			split_huge_page(page);
+			unlock_page(page);
 		}
 	}
 }