Re: Segment override and lldt instruction

[Frank Kotler <fbkotler@xxxxxxxxxxx>]

A D wrote:
> > > Frank Kotler wrote:
> > > In "Linux assembly", there is no reason you'd *want* to use a segment
> > > override, or alter a segment register.
> >
> >
> > Hendrik Visage wrote:
> > Not while your program and/or data space  fits in 4GB of memory space ;)
>
>
> So please correct my understanding if i'm wrong: it is not possible
> or necessary to override segment register in protected mode but one can do
> the same thing in real mode. right?

Right. (In Windows, you might want to do [fs:somevalue] - Windows uses 
fs for "thread local storage"(???) - a descriptor that does *not* have a 
base of 0, and limit is... 64k-1(???)... I think)

> So if answer is yes, and if more 
> than 4GB
> of memory space is needed for a program how will segmentation register go
> beyond 4gig without override?

Dunno. I'll leave that one to Hendrik. :)

Best,
Frank

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