Re: [PATCH 7/10 v2] Generic Watchdog Timer Driver

[Alejandro Cabrera <acabrera@udio.cujae.edu.cu>]

Hi Wim

>>>    static int watchdog_stop(struct watchdog_device *wddev)
>>>    {
>>> -	int err;
>>> +	int err = -1;
>>> +
>>> +	if (test_bit(WDOG_NO_WAY_OUT,&wdd->status))
>>> +		return err;
>>>
>> If you return err at this point you never clean the bit WDOG_ACTIVE then
>> the timer will keep resetting the wdt because the bit is still active.
> If WDOG_ACTIVE is never cleared, then you will need to keep pinging the watchdog
> to not start the reboot. Even when you use the timer (with this code):
>          if (time_before(jiffies, next_heartbeat) ||
>             (!test_bit(WDOG_ACTIVE,&wdt_dev.status))) {
>
> if WDOG_ACTIVE is set then you fall down to: if (time_before(jiffies, next_heartbeat))
> which means that as long that the next_heartbeat time is not there we will keep pinging
> the watchdog device, but as soon as jiffies>  next_heartbeat, the watchdog device will
> not be triggered anymore.
>
> But I see another possible problem here. Will do some special tests first.
>
Sorry, I didn't see the ! operator before test_bit, my mistake !! ;)

best regards
Alejandro

PS: I send a patch some days ago (xilinx watchdog....)...and anyone 
comment it :(. Should I send it again to the list ?



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