Kernel Panic sata_promise with atapi on dual Opteron

[Dave Stubbs <dave.stubbs@utoronto.ca>]

Hello Jeff,

Don't know if you've seen this before, but I thought I should mention it 
since I seem to be able to reproduce it quite reliably.

I am trying to get my new Plextor SATA DVD-RW drive working under 
linux.  I have it hooked up to a Promise SATAII150 TX4 controller, which 
sees it ok during BIOS init.  The system this is all running on is a 
Dual Opteron 246 system on a Tyan Tiger motherboard.

If I enable ATAPI support in include/linux/libata.h and recompile the 
kernel, I get the following when the module tries to load:

Kernel Bug at sata_promise:468
invalid operand 0000 [1] SMP

and then the kernel panics.

This happens the same with 2.6.11.8, 2.6.11.9, and 2.6.11-gentoo-r6.  It 
also happens whether sata_promise is compiled as a module or integrated.

Does this give enough information to make heads or tails of this? 

Thanks very much for your time,

Dave...