Re: IDE disk and HPA

[Oliver Tennert <O.Tennert@science-computing.de>]

On Friday, 22. July 2005 16:47, Alan Cox wrote:
> > Do I interpret it right that the following is done in the above function:
>
> Aside from the version in most kernels being buggy yes
>
> > My question is now: why is an HPA disabled i.e. disprotected when
> > detected? Why not let the HPA alone, because a certain set of disk
> > sectors shall not be accessible by the OS?
>
> Because the HPA is most commonly used to hide all but a fraction of a
> disk to work with older BIOSes.

But as to my knowledge, the HPA was had been introduced to allow HW vendors to 
store things like diagnostic programs in a part of the disk protected from 
partitioning and filesystems. The point is, IF there is an HPA, there MIGHT 
be a partitioning scheme and some filesystems on the disk which rely on the 
size of disk being the native size MINUS the HPA.

Also there might be some contents in the HPA which is vulnerable to deletion 
if exposed to the OS in such a transparent way.

So unconditionally disabling the HPA seems not an unconditionally good idea to 
me.

Why is the HPA not just left alone?

Best regards

Oliver

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