[maemo-developers] debugging spontaneous reboot issues with N800/N810

[From: Aleksandr Koltsoff]

Hello,

Thanks Kalle & Eero for the enlightening comments & info, much appreciated.

Eero Tamminen wrote:
> ext Kalle Valo wrote:
>>> 3) Asterisk marks the application that caused the last wd timeout
>>> operation? (so in this case, the spontaneous reboot was caused by dsp_dld
>>> or it at least seems so?)

Any ideas on the asterisk though? It's only ever set on one name at a time.

>> There is no way to know what cause hardware watchdog reboot. It can be
>> a problem in kernel, or some userspace application taking all the CPU
>> time.

Right. So debugging a spontaneous system reboot is pretty impossible
after the hw watchdog triggers, if I understand correctly.

Any ideas on how to proceed though? I'd like to post a bug, but without
any ideas on what is causing the reboot, the bug report isn't going to
be very useful to anyone.

> Some process just taking all CPU doesn't cause HW watchdog reboot.
> Some OOM-protected[1] process (such as Desktop) taking all memory
> (e.g. due to a leak in an applet) so that kernel spends all time
> just suffling memory pages can cause it though.
> 
> [1] OOM-protected = processes ignored by the kernel out of memory
>     killer. Applications (such as Browser) are not not OOM-protected.
>     If they use too much memory, kernel kills them to protect
>     rest of the system.  (before this allocations are denied to
>     them, but this doesn't help if other processes in the system
>     need more memory too)

Only processes on the OOM-protected list will be protected, right? This
would imply that by default any other process would fall under the
OOM-killer in the kernel (which makes sense).

ak.