ATA driver races with interrupts

[Ville-Pertti Keinonen]

Ville-Pertti Keinonen wrote:

>
> I'm definitely not convinced of its correctness, since I'm not sure 
> which part of the code is 

I've spent too much time away from kernel code.  Now that I think about 
it, obviously it'll break things on systems with edge-triggered 
interrupts, so don't try the patch on old ISA boxes...

I think I need to read more code in order to get back up-to-date with 
the new FreeBSD interrupt mechanisms before trying again.