diff --git a/[refs] b/[refs]
index e9f3feb38bc5..67f58e9d1175 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 834b40380e93e36f1c9b48ec1d280cebe3d7bd8c
+refs/heads/master: 8d056cb965b8fb7c53c564abf28b1962d1061cd3
diff --git a/trunk/mm/filemap.c b/trunk/mm/filemap.c
index 61ba5e405791..4ee2e998e937 100644
--- a/trunk/mm/filemap.c
+++ b/trunk/mm/filemap.c
@@ -1029,6 +1029,9 @@ static void do_generic_file_read(struct file *filp, loff_t *ppos,
 				goto page_not_up_to_date;
 			if (!trylock_page(page))
 				goto page_not_up_to_date;
+			/* Did it get truncated before we got the lock? */
+			if (!page->mapping)
+				goto page_not_up_to_date_locked;
 			if (!mapping->a_ops->is_partially_uptodate(page,
 								desc, offset))
 				goto page_not_up_to_date_locked;