On Wed, Mar 20, 2019 at 03:30:39PM +0000, 王 文涛 wrote:
> From: Wentao Wang <witallwang@xxxxxxxxx>
>
> Echo "" to /sys/module/kgdboc/parameters/kgdboc will fail with "No such device” error.
>
> This is caused by function "configure_kgdboc" who init err to ENODEV when the config
> is empty (legal input) the code go out with ENODEV returned.
>
> Fixes: 2dd453168643d ("kgdboc: Fix restrict error")
>
> Signed-off-by: Wentao Wang <witallwang@xxxxxxxxx>
Acked-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
Thanks!
Daniel.
> ---
> drivers/tty/serial/kgdboc.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
> index 6fb312e..bfe5e9e 100644
> --- a/drivers/tty/serial/kgdboc.c
> +++ b/drivers/tty/serial/kgdboc.c
> @@ -148,8 +148,10 @@ static int configure_kgdboc(void)
> char *cptr = config;
> struct console *cons;
>
> - if (!strlen(config) || isspace(config[0]))
> + if (!strlen(config) || isspace(config[0])) {
> + err = 0;
> goto noconfig;
> + }
>
> kgdboc_io_ops.is_console = 0;
> kgdb_tty_driver = NULL;
> --
> 2.7.4
>
