Comment # 12 on bug 1042933 from Thomas Blume

(In reply to Borislav Petkov from comment #11)
> (In reply to Thomas Blume from comment #10)
> > You hit the nail.
> > The watchdog test takes ages.
> 
> I C.
> 
> > The only question is now why it takes so long on SUSE whereas on
> > RH/Debian 10s are apparently sufficient.
> 
> Add more debugging output :-)

Here is a summary of my findings:

The code sets the watchdog timeout and then does a loop for pinging the
watchdog 5 times. On each iteration it sleeps for half of the watchdog timeout.
The watchdog_ping function opens the watchdog but doesn't call watchdog_close
after the ping is finished. Only the watchdog_close function contains the code
to stop the watchdog timer with the methods mentioned in commment#6.
This function is called only after the loop has finished which summarizes to a
minimum time of 5*watchdog_timeout/2 for the test.
Obviously this much too high for the timeout.

Boris, I'm wondering when exactly the watchdog timer starts counting down.
Is it when opening /dev/watchdog or when doing the ping (ioctl(watchdog_fd,
WDIOC_KEEPALIVE, 0) or something else?