[dm-devel] dm bufio: fix missed destroy of mutex c->lock

[Mike Snitzer]

I already staged a similar fix, see:
https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=dm-4.16&id=cfb0bd8b25eb90faa7cbbad9a52ad2c33102123e

On Thu, Jan 04 2018 at  9:08am -0500,
Xiongwei Song <sxwjean at gmail.com> wrote:

> The mutex c->lock is initialized in dm_bufio_client_create, however,
> it is not destroyed before free the structure of dm_bufio_client in
> dm_bufio_client_destroy.
> 
> Signed-off-by: Xiongwei Song <sxwjean at gmail.com>
> ---
>  drivers/md/dm-bufio.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
> index c546b567f3b5..53c0d5d2039a 100644
> --- a/drivers/md/dm-bufio.c
> +++ b/drivers/md/dm-bufio.c
> @@ -1811,6 +1811,7 @@ void dm_bufio_client_destroy(struct dm_bufio_client *c)
>  		BUG_ON(c->n_buffers[i]);
>  
>  	dm_io_client_destroy(c->dm_io);
> +	mutex_destroy(&c->lock);
>  	kfree(c);
>  }
>  EXPORT_SYMBOL_GPL(dm_bufio_client_destroy);
> -- 
> 2.15.1
>