Promise SATA 300 TX4 cause

[Nathan Butcher]

After some poking around, I can confirm Karsten's report that it is
indeed the following edit that causes problems with the Promise card:

http://lists.freebsd.org/pipermail/cvs-src/2007-June/079930.html

a csup with date=2007.06.16.03.00.00 is ok, but a csup with
date=2007.06.16.06.00.00 introduces the vm updates and breaks the
operation of the card (resulting in many checksum errors in my ZFS pool,
and an eventual system lockup after a good amount of time)