Re: [RFC] Restoring HDIO_GETGEO semantics (was: Re: workaround for BIOS / CHS stuff)

Andrew Clausen
2004-07-03T02:55:48Z

On Fri, Jul 02, 2004 at 02:45:50PM -0400, Patrick J. LoPresti wrote:
> > 2) use EDD, it does a much better job -- maybe this suggestions
> > doesn't make much sense overall, so only 1) left if you don't
> > want to keep guessing.
>
> Using EDD to deduce the geometry is the "right" answer. But this is
> sufficiently complex and special-purpose that it has no place in the
> kernel.

You think it should be in user-space? I don't think talking to the
BIOS should ever be in user-space.

> > > The only case I see where absolutely something is needed is the
> > > case of partitioning an empty disk.
> >
> > Recovery, cloning, ...
>
> ...moving a drive between machines...
>
> Why does this stupid idea keep coming up? Inferring the geometry from
> the existing partition table is just plain wrong. It is even more
> wrong than the old 2.4 behavior, because it is still a guess, just a
> worse guess.

Didn't the old 2.4 behaviour include BIOS queries?

In any case, I don't have any evidence that anything is wrong. On my
computer, I can tell the BIOS to use CHS geometry, (as opposed to
"Auto", "LBA" or "Large") modify the partition table to set the CHS
start/end of the Windows partition to 0, 1024, or anything I like, and
Windows STILL works. I can't get anything to break!

So, can anyone break Windows?

Cheers,
Andrew