Sata controller order

[Stuart Gall <stuart@otenet.gr>]

Hello,
I have a problem with 4.0r2 (although it is probably not exclusive to 
that release)

On a number of systems with multiple sata controllers the controllers 
come up in different orders (randomly on boot) the order is always the 
same in lilo but gets changed sometimes by the time the kernel loads.
This has the effect of juggling the drives so mount does not work.

I have seen this problem in a number of places on the net, the usual 
solution posted is to mount by label rather than by drive.

This is possible for EXT2/EXT3 but it is not possile AFAIKS for swap. 
Also the reason these systems have multiple sata controllers is that 
they have a raid partition. So also I am not sure how the md device 
would handle having its disks moved around.

Is there some way to force a particular controller, and hence disk, 
ordering on the kernel ?

For the moment, if these systems have to be shutdown. On reboot if the 
order is wrong we get dumped to ramfs then we just ctrl-alt-delete 
repeatedly until the order comes right and the system boots.

I can not understand why the order would be random.

I am using irqpoll kernel flag to boot these systems, otherwise we get 
sda lost interrupt, not sure if that is relevant.

TVMIA

Stuart