Re: [PATCH] zonefs: Fix race between modprobe and mount

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 11/20/22 19:57, Zhang Xiaoxu wrote:
> There is a race between modprobe and mount as below:
> 
>  modprobe zonefs                | mount -t zonefs
> --------------------------------|-------------------------
>  zonefs_init                    |
>   register_filesystem       [1] |
>                                 | zonefs_fill_super    [2]
>   zonefs_sysfs_init         [3] |
> 
> 1. register zonefs suceess, then
> 2. user can mount the zonefs
> 3. if sysfs initialize failed, the module initialize failed.
> 
> Then the mount process maybe some error happened since the module
> initialize failed.
> 
> Let's register zonefs after all dependency resource ready. And
> reorder the dependency resource release in module exit.
> 
> Fixes: 9277a6d4fbd4 ("zonefs: Export open zone resource information through sysfs")
> Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>

Applied to for-6.1-fixes. Thanks !

> ---
>  fs/zonefs/super.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c
> index 860f0b1032c6..625749fbedf4 100644
> --- a/fs/zonefs/super.c
> +++ b/fs/zonefs/super.c
> @@ -1905,18 +1905,18 @@ static int __init zonefs_init(void)
>  	if (ret)
>  		return ret;
>  
> -	ret = register_filesystem(&zonefs_type);
> +	ret = zonefs_sysfs_init();
>  	if (ret)
>  		goto destroy_inodecache;
>  
> -	ret = zonefs_sysfs_init();
> +	ret = register_filesystem(&zonefs_type);
>  	if (ret)
> -		goto unregister_fs;
> +		goto sysfs_exit;
>  
>  	return 0;
>  
> -unregister_fs:
> -	unregister_filesystem(&zonefs_type);
> +sysfs_exit:
> +	zonefs_sysfs_exit();
>  destroy_inodecache:
>  	zonefs_destroy_inodecache();
>  
> @@ -1925,9 +1925,9 @@ static int __init zonefs_init(void)
>  
>  static void __exit zonefs_exit(void)
>  {
> +	unregister_filesystem(&zonefs_type);
>  	zonefs_sysfs_exit();
>  	zonefs_destroy_inodecache();
> -	unregister_filesystem(&zonefs_type);
>  }
>  
>  MODULE_AUTHOR("Damien Le Moal");

-- 
Damien Le Moal
Western Digital Research