diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index b33d04250bbc..12d58a7ed6bc 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -2859,11 +2859,8 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon
 			ioctl_result = st_int_ioctl(STp, MTBSF, 1);
 
 		if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
-			int old_block_size = STp->block_size;
 			STp->block_size = arg & MT_ST_BLKSIZE_MASK;
 			if (STp->block_size != 0) {
-				if (old_block_size == 0)
-					normalize_buffer(STp->buffer);
 				(STp->buffer)->buffer_blocks =
 				    (STp->buffer)->buffer_size / STp->block_size;
 			}