Hi... On Tue, Sep 13, 2011 at 11:55, Kaustubh Ashtekar <ksashtekar@xxxxxxxxx> wrote: > > > On Fri, Sep 9, 2011 at 5:51 PM, sandeep kumar <coolsandyforyou@xxxxxxxxx> > wrote: >> >> Hi all, >> I wanted to manipulate the watchdog timer driver to see how it works in >> deadlocks. > > >> >> <snip> > > >> >> My question is this, >> When watch dog timer expires(hardware watchdog), its interrupt directly >> resets the system >> (or) it is treated as an interrupt and a handler is executed. > > AFAIK, after the watchdog is triggered, the SoC/processor is completely > reset including all the peripherals. The main purpose of a watchdog is to > reset a processor which has locked up somewhere in some thread (with > interrupts disabled, maybe), effectively starving the thread which is > supposed to reset the watchdog periodically. Just to add, AFAIK watchdog is used in "locked" scenario because it can't be masked and disabled...and it receives highest priority in trap/interrupt by the processors. AFAIK too, in most scenarios, handler is placed to picked up watchdog signal...and it is this handler which is then fix the situation. Only my 2 cents idea... -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
