Re: [PATCH 4/5] fs: make FSCONFIG_CMD_RECONFIGURE killable on s_umount

[Jan Kara]

On Fri 23-10-26 20:39:33, Josef Bacik wrote:
> fsconfig(2) with FSCONFIG_CMD_RECONFIGURE is the remount of the new mount
> API, and like mount(2) with MS_REMOUNT it waits for s_umount in D state,
> can't be killed, and keeps every later reader of the lock waiting behind
> it.
> 
> Use down_write_killable().  A wait which is cut short is treated like any
> other failure to reconfigure, the context ends up in FS_CONTEXT_FAILED.
> 
> Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

							Honza

> ---
>  fs/fsopen.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/fsopen.c b/fs/fsopen.c
> index 70024870fefa..c139cec2f1fe 100644
> --- a/fs/fsopen.c
> +++ b/fs/fsopen.c
> @@ -267,9 +267,11 @@ static int vfs_cmd_reconfigure(struct fs_context *fc)
>  		return -EPERM;
>  	}
>  
> -	down_write(&sb->s_umount);
> -	ret = reconfigure_super(fc);
> -	up_write(&sb->s_umount);
> +	ret = down_write_killable(&sb->s_umount);
> +	if (!ret) {
> +		ret = reconfigure_super(fc);
> +		up_write(&sb->s_umount);
> +	}
>  	if (ret) {
>  		fc->phase = FS_CONTEXT_FAILED;
>  		return ret;
> 
> -- 
> 2.55.0
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR