ext4: use EXT4_BAD_INO for buddy cache to avoid colliding with valid inode #
Signed-off-by: Yu Jian <yujian@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 70d1b3e..e41620b 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2342,7 +2342,11 @@
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);