diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index b37c136ea3ab..84148b25370e 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -334,7 +334,7 @@ struct ext4_io_submit {
 #define	EXT4_MAX_BLOCK_SIZE		65536
 #define EXT4_MIN_BLOCK_LOG_SIZE		10
 #define EXT4_MAX_BLOCK_LOG_SIZE		16
-#define EXT4_MAX_CLUSTER_LOG_SIZE	30
+#define EXT4_MAX_CLUSTER_LOG_SIZE	28
 #ifdef __KERNEL__
 # define EXT4_BLOCK_SIZE(s)		((s)->s_blocksize)
 #else