From: Theodore Ts'o Subject: [PATCH 4/5] ext4: use EXT4_BAD_INO for buddy cache to avoid colliding with valid inode # Date: Mon, 1 Aug 2011 09:13:17 -0400 Message-ID: <1312204398-12460-5-git-send-email-tytso@mit.edu> References: <1312204398-12460-1-git-send-email-tytso@mit.edu> Cc: Yu Jian , Andreas Dilger , "Theodore Ts'o" To: Ext4 Developers List Return-path: Received: from li9-11.members.linode.com ([67.18.176.11]:40449 "EHLO test.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751841Ab1HANNV (ORCPT ); Mon, 1 Aug 2011 09:13:21 -0400 In-Reply-To: <1312204398-12460-1-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Yu Jian Signed-off-by: Yu Jian Signed-off-by: Andreas Dilger Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 262fa47..8beccd8 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2342,7 +2342,11 @@ static int ext4_mb_init_backend(struct super_block *sb) ext4_msg(sb, KERN_ERR, "can't get new inode"); goto err_freesgi; } - sbi->s_buddy_cache->i_ino = get_next_ino(); + /* To avoid potentially colliding with an valid on-disk inode number, + * use EXT4_BAD_INO for the buddy cache inode number. This inode is + * not in the inode hash, so it should never be found by iget(), but + * this will avoid confusion if it ever shows up during debugging. */ + sbi->s_buddy_cache->i_ino = EXT4_BAD_INO; EXT4_I(sbi->s_buddy_cache)->i_disksize = 0; for (i = 0; i < ngroups; i++) { desc = ext4_get_group_desc(sb, i, NULL); -- 1.7.4.1.22.gec8e1.dirty