--- 21bb2f61e50223c2da0946c4b48db0e4c947e1a7
+++ b5c25ba59f7de9fab9fbd6720d9fd8351dbe64d1
@@ -285,8 +285,12 @@ out:
 		if (!fatal)
 			fatal = err;
 		ext4_mark_super_dirty(sb);
-	} else
+	} else {
+		/* for debugging, sangwoo2.lee */
+		print_bh(sb, bitmap_bh, 0, EXT4_BLOCK_SIZE(sb));
+		/* for debugging */
 		ext4_error(sb, "bit already cleared for inode %lu", ino);
+	}
 
 error_return:
 	brelse(bitmap_bh);