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SubjectRe: 2.1.93..
Hello,

> <groan> You would have to ask that. Unfortunately, there's no way to predict
> what the system BIOS will do. It depends on the order that each of the BIOS
> extensions on the host adapters are executed by the system BIOS, and there's no
> standard for this at all. Some system BIOS identify all the BIOS extensions on
> peripheral cards and then sort them by increasing size, others by decreasing
> size, and some simply by slot order. Then they must be copied to low memory
> for execution. Whichever BIOS extension gets control first will generally
> probe for devices and then install the disks the BIOS understands by hooking
> the appropriate interrupt(s). Note also that once a BIOS extension executes it
> can shrink itself back to a smaller resident size, so fitting everything
> sometimes depends on the recognition order. It's not pretty at all. Certin
> combinations of cards can only be used in a specific order in certain
> motherboards because of this. It's a tech support nightmare.

# Since there is nothing in Linux that ensures that devices are numbered
# according to the _actual_ BIOSes order, any tool based on such an
# assumption is essentially broken.

IMHO only few users have more than one SCSI controllers and I think we can
ask them to specify BIOS number for the disk they want to boot from manually.

Anyway, I've written a patch to PCI subsystem which uses BIOS ordering
while still using direct hw access for touching configuration registers,
but I think we should remove all this compatibility glue in 2.3.

| Hmmm... not mentioned in the man page. Also, we're straying

Probably not in the man page, but I'm sure it's mentioned in the
documentation.

Have a nice fortnight
--
Martin `MJ' Mares <mj@ucw.cz> http://atrey.karlin.mff.cuni.cz/~mj/
Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth
"If at first you don't succeed, you must be using Windows ..."

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