GEOM causes kernel panic

[Joshua Bell]

  When ever I try to transfer large filesets to the raid after getting it setup and mounted, the server panics and reboots.  Once the server is back online, the raid is set in `stale` and the kernel panics if I try to start the raid up.

  It is weird, as I can easily manipulate small files and use the drives as normal untill I attempt to transfer files onto the drives.  I am getting no error messages remotely when attempting to restart the raid.

This is the same problem that I experienced on 5.4-release, and am still experiencing on 5.4-stable.

-Josh