diff --git a/servers/mfs/cache.c b/servers/mfs/cache.c
index 7acb0f048..d64dcc228 100644
--- a/servers/mfs/cache.c
+++ b/servers/mfs/cache.c
@@ -381,11 +381,6 @@ PUBLIC void invalidate(
  *===========================================================================*/
 int block_write_ok(struct buf *bp)
 {
-	/* XXX this check is temporarily disabled as it's incompatible with
-	 * updating the sector list in the bootcode. This will change when
-	 * we switch to the netbsd-based bootloader.
-	 */
-#if 0
 	if(superblock.s_dev != bp->b_dev) return 1;
 
 	if(bp->b_blocknr >= super_start && bp->b_blocknr <= super_end) {
@@ -398,7 +393,6 @@ int block_write_ok(struct buf *bp)
 		printf("This shouldn't happen.\n");
 		return 0;
 	}
-#endif
 
 	return 1;
 }