On Fri, Jun 22, 2012 at 09:24:12PM +0300, Ilya Dryomov wrote:
> Fix a bug that triggered asserts in btrfs_balance() in both normal and
> resume modes -- restriper state was not properly restored on read-only
> mounts. This factors out resuming code from btrfs_restore_balance(),
> which is now also called earlier in the mount sequence to avoid the
> problem of some early writes getting the old profile.
>
> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
> ---
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 77872da..dae7cd6 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -2492,9 +2497,6 @@ retry_root_backup:
> err = btrfs_orphan_cleanup(fs_info->tree_root);
> up_read(&fs_info->cleanup_work_sem);
>
> - if (!err)
> - err = btrfs_recover_balance(fs_info->tree_root);
> -
> if (err) {
> close_ctree(tree_root);
> return err;
> @@ -2518,6 +2520,9 @@ fail_cleaner:
> fail_block_groups:
> btrfs_free_block_groups(fs_info);
>
> +fail_balance_ctl:
> + kfree(fs_info->balance_ctl);
I think you need to set fs_info->balance_ctl to NULL, otherwise this
could lead to double free from free_fs_info. I was looking along the
call paths and didn't see free_fs_info called on the mount failure path:
vfs->mount
btrfs_mount
btrfs_fill_super
open_ctree
(recover balance fails, frees ctl)
error is propagated back to vfs, no other fs callback is done (like
kill_super which does call free_fs_info).
The only exit path that is not going through free_fs_info is after error
from btrfs_fill_super, and this can fail from various reasons.
Either I'm missing something, or we leak a btrfs_fs_info every time a
mount fails ...
Back to your patch, apart from the balance_ctl pointer reset, both are
ok and given the number of bug reports [useless padding text here]
this should go to 3.5-rc.
david
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
