Re: watchdog timer programming

mike tancsa <mike@sentex.net> writes:

> I also started to play around with the non hardware based 
> watchdog
> timer.  For some reason, I cant get the box to reboot. It just 
> prints a
> stack trace and continues
>
> This is with no driver loaded.
>
> 0{t}# watchdogd --softtimeout-action panic -t 5
> 0{t}# ps -auxww | grep dog
> root     1487   0.4  0.2   12820  12920  -  S<s  09:03 0:00.01 
> watchdogd
> --softtimeout-action panic -t 5
> root     1489   0.0  0.0   12808   2636 u0  S+   09:03 
> 0:00.00
> grep dog
> 0{t}# kill -9 1487
> 0{t}# KDB: stack backtrace:
> #0 0xffffffff80b7fefd at kdb_backtrace+0x5d
> #1 0xffffffff80abec93 at hardclock+0x103
> #2 0xffffffff80abfe8b at handleevents+0xab
> #3 0xffffffff80ac0b7c at timercb+0x24c
> #4 0xffffffff810d0ebb at lapic_handle_timer+0xab
> #5 0xffffffff80fd8a71 at Xtimerint+0xb1
> #6 0xffffffff804b3685 at acpi_cpu_idle+0x2c5
> #7 0xffffffff80fc48f6 at cpu_idle_acpi+0x46
> #8 0xffffffff80fc49ad at cpu_idle+0x9d
> #9 0xffffffff80b67bb6 at sched_idletd+0x576
> #10 0xffffffff80aecf7f at fork_exit+0x7f
> #11 0xffffffff80fd7dae at fork_trampoline+0xe
>
> 0{t}#
>
> Should it not reboot at this point ?

I don't think so. `kdb_backtrace` being involved let me think the
kernel was compiled with KDB. You should play with ddb(8) to set a
default action like reset when entering kdb.

Regards,
-- 
Stéphane Rochoy
O: Stormshield