Re: [PATCH 2/2] ubi: ubi_init: Fix missed ubiblock cleanup in error handling path

Daniel Golle
2024-04-10T23:11:15Z

Hi!

On Wed, Apr 10, 2024 at 03:40:33PM +0800, Zhihao Cheng wrote:
> The ubiblock_init called by ubi_init will register device number, but
> device number is not released in error handling path of ubi_init when
> ubi is loaded by inserting module (eg. attaching failure), which leads
> to subsequent ubi_init calls failed by running out of device number
> (dmesg shows that "__register_blkdev: failed to get major for ubiblock").
> Fix it by invoking ubiblock_exit() in corresponding error handling path.

Thank you for taking care of this issue.

See my comment inline below:

>
> Fixes: 927c145208b0 ("mtd: ubi: attach from device tree")
> Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
> ---
> drivers/mtd/ubi/build.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
> index 7f95fd7968a8..354517194099 100644
> --- a/drivers/mtd/ubi/build.c
> +++ b/drivers/mtd/ubi/build.c
> @@ -1380,12 +1380,13 @@ static int __init ubi_init(void)
> if (ubi_is_module()) {
> err = ubi_init_attach();
> if (err)
> - goto out_mtd_notifier;
> + goto out_block_exit;
> }
>
> return 0;
>
> -out_mtd_notifier:
> +out_block_exit:
> + ubiblock_exit();

I believe that this call is the reason for the section mismatch we
are seeing on Intel's kernel test builds:

https://lore.kernel.org/oe-kbuild-all/202404110656.wLLc5mHR-lkp@intel.com/

Also note that Ben Hutchings has supplied a more complete and imho
better solution for this problem, which yet still suffers from the
same problem (calling __exit function from __init function which
results in section mismatch).

> unregister_mtd_user(&ubi_mtd_notifier);
> out_debugfs:
> ubi_debugfs_exit();
> --
> 2.39.2
>