diff --git a/fs/buffer.c b/fs/buffer.c
index 9a73924db22f988df19662e45d534950a4c174f4..ec5dd39071e6a308c0c6eefea15d13db3bd6576d 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1511,7 +1511,7 @@ void block_invalidatepage(struct page *page, unsigned int offset,
 	 * The get_block cached value has been unconditionally invalidated,
 	 * so real IO is not possible anymore.
 	 */
-	if (offset == 0)
+	if (length == PAGE_SIZE)
 		try_to_release_page(page, 0);
 out:
 	return;