gs_change ... kswapd0 exited with preempt_count 1

Hi,

I am chasing a bug I cannot make any sense of: I have a i7 based server on an intel board that runs just fine for days but then suddenly dies with the backtraces below on git master but also any older kernel version I tried. The system is running this config
http://7nn.de/debugging/config.gz

And no matter what I do I keep getting kernel panics after a couple of days (or weeks) that all involve kswapd0 / gs_change:

http://7nn.de/debugging/panic-3.2.0.jpg
http://7nn.de/debugging/panic-3.3.0-rc5.jpg

Any ideas,
Soeren

For the one fact about the future of which we can be certain is that it
will be utterly fantastic. -- Arthur C. Clarke, 1962