diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index 046a2515e309..5cc6e6837a92 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -228,7 +228,7 @@ static int unpack_compacted_index(struct z_erofs_maprecorder *m,
 	u8 *in, type;
 	bool big_pcluster;
 
-	if (1 << amortizedshift == 4)
+	if (1 << amortizedshift == 4 && lclusterbits <= 14)
 		vcnt = 2;
 	else if (1 << amortizedshift == 2 && lclusterbits == 12)
 		vcnt = 16;
@@ -321,7 +321,6 @@ static int compacted_load_cluster_from_disk(struct z_erofs_maprecorder *m,
 {
 	struct inode *const inode = m->inode;
 	struct erofs_inode *const vi = EROFS_I(inode);
-	const unsigned int lclusterbits = vi->z_logical_clusterbits;
 	const erofs_off_t ebase = ALIGN(iloc(EROFS_I_SB(inode), vi->nid) +
 					vi->inode_isize + vi->xattr_isize, 8) +
 		sizeof(struct z_erofs_map_header);
@@ -331,9 +330,6 @@ static int compacted_load_cluster_from_disk(struct z_erofs_maprecorder *m,
 	erofs_off_t pos;
 	int err;
 
-	if (lclusterbits != 12)
-		return -EOPNOTSUPP;
-
 	if (lcn >= totalidx)
 		return -EINVAL;