commit 34f3e4f23ca3d259fe078f62a128d97ca83508ef
Author: liubo <liubo2...@cn.fujitsu.com>
Date:   Sat Aug 6 08:35:23 2011 +0000

    Btrfs: fix an oops of log replay

    When btrfs recovers from a crash, it may hit the oops below:

    ------------[ cut here ]------------
    kernel BUG at fs/btrfs/inode.c:4580!
    [...]
    RIP: 0010:[<ffffffffa03df251>]  [<ffffffffa03df251>] 
btrfs_add_link+0x161/0x1c0 [btrfs]
    [...]
    Call Trace:
     [<ffffffffa03e7b31>] ? btrfs_inode_ref_index+0x31/0x80 [btrfs]
     [<ffffffffa04054e9>] add_inode_ref+0x319/0x3f0 [btrfs]
     [<ffffffffa0407087>] replay_one_buffer+0x2c7/0x390 [btrfs]
     [<ffffffffa040444a>] walk_down_log_tree+0x32a/0x480 [btrfs]
     [<ffffffffa0404695>] walk_log_tree+0xf5/0x240 [btrfs]
     [<ffffffffa0406cc0>] btrfs_recover_log_trees+0x250/0x350 [btrfs]
     [<ffffffffa0406dc0>] ? btrfs_recover_log_trees+0x350/0x350 [btrfs]
     [<ffffffffa03d18b2>] open_ctree+0x1442/0x17d0 [btrfs]
    [...]

    This comes from that while replaying an inode ref item, we forget to
    check those old conflicting DIR_ITEM and DIR_INDEX items in fs/file tree,
    then we will come to conflict corners which lead to BUG_ON().

    Signed-off-by: Liu Bo <liubo2...@cn.fujitsu.com>
    Tested-by: Andy Lutomirski <l...@mit.edu>
    Signed-off-by: Chris Mason <chris.ma...@oracle.com>

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index babee65..786639f 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -799,14 +799,15 @@ static noinline int add_inode_ref(struct 
btrfs_trans_handle *trans,
                                  struct extent_buffer *eb, int slot,
                                  struct btrfs_key *key)
 {
-       struct inode *dir;
-       int ret;
        struct btrfs_inode_ref *ref;
+       struct btrfs_dir_item *di;
+       struct inode *dir;
        struct inode *inode;
-       char *name;
-       int namelen;
        unsigned long ref_ptr;
        unsigned long ref_end;
+       char *name;
+       int namelen;
+       int ret;
        int search_done = 0;

        /*
@@ -909,6 +910,25 @@ again:
        }
        btrfs_release_path(path);

+       /* look for a conflicting sequence number */
+       di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir),
+                                        btrfs_inode_ref_index(eb, ref),
+                                        name, namelen, 0);
+       if (di && !IS_ERR(di)) {
+               ret = drop_one_dir_item(trans, root, path, dir, di);
+               BUG_ON(ret);
+       }
+       btrfs_release_path(path);
+
+       /* look for a conflicing name */
+       di = btrfs_lookup_dir_item(trans, root, path, btrfs_ino(dir),
+                                  name, namelen, 0);
+       if (di && !IS_ERR(di)) {
+               ret = drop_one_dir_item(trans, root, path, dir, di);
+               BUG_ON(ret);
+       }
+       btrfs_release_path(path);
+
 insert:
        /* insert our name */
        ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,

_______________________________________________
stable mailing list
stable@linux.kernel.org
http://linux.kernel.org/mailman/listinfo/stable

Reply via email to