With this applied, my machine has stopped all those painful messages.
dmesg now says :

root@riri:/Kernels# dmesg | grep LBA
ata1.00: 490234752 sectors, multi 0: LBA48 NCQ (not used)
ata2.00: 640 sectors, multi 1: LBA
ata3.00: 490234752 sectors, multi 0: LBA48 NCQ (not used)
Signed-off-by: Paul Rolland <rol@as2917.net>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>