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Date: Wed, 10 Aug 2011 18:24:28 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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To: Steven Hartland <killing@multiplay.co.uk>
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Cc: freebsd-stable@FreeBSD.org
Subject: Re: debugging frequent kernel panics on 8.2-RELEASE
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on 10/08/2011 17:22 Steven Hartland said the following:
> The kernel is compiled with:-
> options     KDB         # Kernel debugger related code
> options     KDB_TRACE       # Print a stack trace for a panic

You also have to provide an actual debugger backend like built-in DDB or a stub
for remote GDB to get online debugging.  No guarantees that that would help you to
get the debugging information, but without that the chances are even slimmer.

You may also try this patch and see if it provides any improvements for post-panic
environment (dumping etc):
http://people.freebsd.org/~avg/stop_scheduler_on_panic.8.x.diff

It might also be a good idea to at least capture a screenshot of whatever
information you get on console when the panic happens.

-- 
Andriy Gapon