[syslinux] BIOS disk geometry and Linux 2.6

[H. Peter Anvin]

Patrick J. LoPresti wrote:
> 
> This still does not let you do the mapping in general.  Any drive
> might have been moved from any machine.

And then you need to install, so you have to make sure this program runs

> Or do you clobber sector 1 on every attached drive?  Seems risky...

That's the idea.

> And don't some boot loaders use sector 1?

None that I know of.  I know someone on this list (Murali?) is 
successfully using it for some installation stuff.

> Just out of curiosity, why is it such a bad idea to pass the geometry
> as a kernel parameter?

It just doesn't buy you anything.

> I suppose it might be better just to add a field to the EDD data and
> fill it in from setup.S...  Hm.

I believe this is the right thing to do.

> I still think the geometry issue and the device mapping issue are
> completely independent and need to be solved separately.
> 
> The geometry issue is critical for me, and it can be solved without
> any scribbling on the disk just by asking the BIOS a few questions.
> 
> The device mapping issue is harder, but on the other hand it is about
> 1000 times less important.  Almost all of my users only have one
> drive; for the rest, I am happy to tell them "use a newer BIOS or
> choose the boot device manually".  And even without EDD 3, I can take
> a pretty good guess at the boot device.

Well, what you should do, then, is ask the EDD patch authors to make the 
data available even if it's incomplete.

	-hpa