Re: [RFC] [PATCH 6/10] Generic Watchdog Timer Driver

[Mike Waychison <mikew@google.com>]

On 02/23/11 12:43, Wim Van Sebroeck wrote:
> commit afe3de93859443b575407f39a2e655956c02e088
> Author: Wim Van Sebroeck<wim@iguana.be>
> Date:   Sun Jul 18 10:39:00 2010 +0000
>
>      watchdog: WatchDog Timer Driver Core - Part 6
>
>      Since we don't want that a driver module can be removed
>      while the watchdog timer is still active, we lock the
>      driver module (by incremeting the reference counter).
>      After a clean close of the watchdog driver we unlock the
>      driver module.
>      If /dev/watchdog is closed uncleanly (and the watchdog is
>      still active) then we do not unlock the driver module,
>      but keep it, so that next time /dev/watchdog get's opened
>      we can continue triggering the watchdog.
>
>      Signed-off-by: Alan Cox<alan@lxorguk.ukuu.org.uk>
>      Signed-off-by: Wim Van Sebroeck<wim@iguana.be>
>

*snip*

> diff --git a/drivers/watchdog/core/watchdog_core.c b/drivers/watchdog/core/watchdog_core.c
> index 52bc520..d1a824e 100644
> --- a/drivers/watchdog/core/watchdog_core.c
> +++ b/drivers/watchdog/core/watchdog_core.c
> @@ -60,6 +60,10 @@ int register_watchdogdevice(struct watchdog_device *wdd)
>   	if (wdd == NULL || wdd->info == NULL || wdd->ops == NULL)
>   		return -ENODATA;
>
> +	/* Make sure that the owner of the watchdog operations exists */
> +	if (wdd->ops->owner == NULL)
> +		return -ENODATA;

This check is invalid when the driver is built in.