diff mbox series

watchdog: only run driver set_pretimeout op if device supports it

Message ID 1624751265-24785-1-git-send-email-curtis.klein@hpe.com
State New
Headers show
Series watchdog: only run driver set_pretimeout op if device supports it | expand

Commit Message

Curtis Klein June 26, 2021, 11:47 p.m. UTC
Some watchdog devices might conditionally support pretimeouts (e.g. if
an interrupt is exposed for the device) but some watchdog drivers might
still define the set_pretimeout operation (e.g. the mtk_wdt driver) and
indicate support at runtime through the WDIOF_PRETIMEOUT flag. If the
kernel is compiled with CONFIG_WATCHDOG_HRTIMER_PRETIMEOUT enabled,
watchdog_set_pretimeout would run the driver specific set_pretimeout
even if WDIOF_PRETIMEOUT is not set which might have unintended
consequences.

So this change checks that the device flags and only runs the driver
operation if pretimeouts are supported.

Signed-off-by: Curtis Klein <curtis.klein@hpe.com>
---
 drivers/watchdog/watchdog_dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Guenter Roeck June 27, 2021, 3:01 p.m. UTC | #1
On 6/26/21 4:47 PM, Curtis Klein wrote:
> Some watchdog devices might conditionally support pretimeouts (e.g. if

> an interrupt is exposed for the device) but some watchdog drivers might

> still define the set_pretimeout operation (e.g. the mtk_wdt driver) and

> indicate support at runtime through the WDIOF_PRETIMEOUT flag. If the

> kernel is compiled with CONFIG_WATCHDOG_HRTIMER_PRETIMEOUT enabled,

> watchdog_set_pretimeout would run the driver specific set_pretimeout

> even if WDIOF_PRETIMEOUT is not set which might have unintended

> consequences.

> 

> So this change checks that the device flags and only runs the driver

> operation if pretimeouts are supported.

> 

> Signed-off-by: Curtis Klein <curtis.klein@hpe.com>


Reviewed-by: Guenter Roeck <linux@roeck-us.net>


> ---

>   drivers/watchdog/watchdog_dev.c | 2 +-

>   1 file changed, 1 insertion(+), 1 deletion(-)

> 

> diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c

> index 3bab324..5bf795c 100644

> --- a/drivers/watchdog/watchdog_dev.c

> +++ b/drivers/watchdog/watchdog_dev.c

> @@ -401,7 +401,7 @@ static int watchdog_set_pretimeout(struct watchdog_device *wdd,

>   	if (watchdog_pretimeout_invalid(wdd, timeout))

>   		return -EINVAL;

>   

> -	if (wdd->ops->set_pretimeout)

> +	if (wdd->ops->set_pretimeout && (wdd->info->options & WDIOF_PRETIMEOUT))

>   		err = wdd->ops->set_pretimeout(wdd, timeout);

>   	else

>   		wdd->pretimeout = timeout;

>
diff mbox series

Patch

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 3bab324..5bf795c 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -401,7 +401,7 @@  static int watchdog_set_pretimeout(struct watchdog_device *wdd,
 	if (watchdog_pretimeout_invalid(wdd, timeout))
 		return -EINVAL;
 
-	if (wdd->ops->set_pretimeout)
+	if (wdd->ops->set_pretimeout && (wdd->info->options & WDIOF_PRETIMEOUT))
 		err = wdd->ops->set_pretimeout(wdd, timeout);
 	else
 		wdd->pretimeout = timeout;