I took a quick look at why 2.5.21 hung at boot detecting partitions,
because a 2.5.22 did the exact same thing on my test box today... The
tcq locking is completely screwed now, and as I said before the weekend
I think the entire locking is just getting worse now.

Anyways, this patch at least attempts to make tcq follow the channel
lock usage to make it work for me.