How to troubleshoot why VirtualBox kernel module freezes the system?

[Alexey Shuvaev]

On Wed, Apr 28, 2010 at 01:18:18PM -0700, Yuri wrote:
> VirtualBox kernel module (port emulators/virtualbox-ose-kmod) began
> to cause system freezes from some kernel change around the end of
> January.
> Once the system freezes it has to be rebooted. Soundcard, if it was
> playing something, begins to cycle some very short piece.
> Nothing is logged into /var/log/messages.
> 
> Is there any way to troubleshoot this, like enabling some kernel
> configuation options?
> What is normally done in such case?
> Should I run system under kernel debugger? But would it detect
> something if it's not a SEGV but the freeze?
> 
Trivial suggestion: have you rebuilt virtualbox with new kernel sources?
What are the versions of FreeBSD / virtualbox?

As a record it is running fine here:
~> uname -a
FreeBSD wep4035 9.0-CURRENT FreeBSD 9.0-CURRENT #0 r206758: Sat Apr 17 17:37:46 CEST 2010     root at wep4035:/usr/obj/usr/src/sys/GENERIC  amd64
~> ls /var/db/pkg/virtualbox-ose-
virtualbox-ose-3.1.6_2/    virtualbox-ose-kmod-3.1.6/

HTH,
Alexey.