Re: [PATCH v3 2/2] watchdog: fix w83627hf_wdt clear timeout expired

[Guenter Roeck <linux@roeck-us.net>]

On Wed, Apr 03, 2013 at 08:06:59AM -0700, Tony Chung wrote:
> On Tue, Apr 2, 2013 at 9:21 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> 
> >
> >
> > What is the exact chip type in your system ? I want to have a look into the
> > datasheet; maybe I can find out how it can trigger without causing a reset.
> 
> Winbond 83627HF chip
> 
> I believe BIOS has watchdog disabled otherwise it would have reboot the box.
> However, the timer just start counting.
> 
> Comparing to ipmi_watchdog, you can do this:
> modprobe ipmi_watchdog ... start_now=0 ...action=<>  nowayout=1
> 
> So it is possible to load the driver without start counting.
> 
That is a different driver, though. you don't have the start_now option here.

> Notice it is an else, so t is actually 0 already (i.e. expired or
> never start running):

Still no idea why that would cause the system to reboot when you reset
the trigger without setting t to 0 again (or why the system doesn't reset
in the first place if the watchdog already triggered).

I am not really sure what the best approach is here, so let's leave it
up to the maintainer to decide which way to go.

Thanks,
Guenter