Hi Wim
I have a doubt about the use of internal timer to reset the wdt when the
watchdog device was closed from userspace and it doesn't support
stopping the wdt.
I think, in my modest opinion, that if the watchdog device was closed at
userspace it means that something is wrong at userspace and the system
needs to be rebooted.
No. the reason why magic_close was introduced in the past is because
there was a need to be able to tell the driver that it could correctly stop.
For instance for maintenance work, where the watchdog device should NOT reboot
the system during the maintenance.
So the reason why we sent that magic char is because we want to tell the driver
that a watchdog daemon will stop working. In that case you do need that timer.
I see...but as I can see in the Generic Watchdog Framework patch series,
the timer only needs that the bit WDOG_ACTIVE active to keep resetting
the wdt....please take a look at my comment about patch number 7
I think that the internal timer can be useful in the following scenario:
If an user reboot the system, then the internal timer must ensure that
the watchdog didn't reset the system during the reboot process and it
send ticks to the wdt until the user/clean reboot process get finished.
Maybe a reboot notifier can be used to detect when the user reboot the
system manually.
If a system is rebooted then the watchdog device is also resetted.
So until you start the watchdog, it will not be activated...
Yes, but I'm thinking in the following case: if the system was
restarting (clean reboot) and it take more than the watchdog timeout or
the timeleft was very small to do a clean reboot....then the wdt reset
the system and maybe it can be corrupt it.
Maybe this case is weird and uncommon, but it has a chance to occur.
Best regards
Alejandro
Participe en Universidad 2012, del 13 al 17 de febrero de 2012.
Habana, Cuba: http://www.congresouniversidad.cu
Consulte la enciclopedia colaborativa cubana. http://www.ecured.cu
Participe en el Segundo Congreso Medio Ambiente Construido y
Desarrollo Sustentable (MACDES 2011) del 6 al 9 de diciembre de 2011,
Hotel Nacional, Habana, Cuba: http://macdes.cujae.edu.cu
--
To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html