Fatal Trap 12 in various processes always at address 0x3030313a

[Gavin Atkinson]

On Sat, 29 Aug 2009, Richard Mahlerwein wrote:

> (Sorry, update to subject to be <something>)
>
> 3 weeks ago:
> I upgraded from 7.1-PRELEASE to -stable and all seemed fine
> until I rebooted out of single user mode after doing make
> installworld and mergemaster.  At that point, near the
> end of the boot sequence I got a core dump, apparently
> triggered by devd.
> 
> ****
> Fatal trap 12: page fault while in kernel mode.
> cpu id = 0; apic id = 00
> fault virtual address = 0x3030313a
> fault code = supervisor write, page not present
> [snip]
> current process = 355 (devd)
> ****
> 
> [snip]
> Does anyone have a further recommendation on what to do,
> try, test or change?

Firstly, please set up a dump partition by adding 'dumpdev="AUTO"' to 
your rc.conf.

Then, can you compile in the kernel debugger (options KGB / options DDB) 
and when this happens again, please obtain a backtrace from the debugger 
with the "bt" command.  Then, give the "show registers" command so that we 
can establish which register is pointing to the odd address. Finally, 
issue the "call doadump()" command to hopefully save a copy of the kernel 
dump for later analysis.

Thanks,

Gavin