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Mail Archives: djgpp-workers/2001/08/27/09:56:23

From: Martin Stromberg <Martin DOT Stromberg AT epl DOT ericsson DOT se>
Message-Id: <200108271356.PAA14341@merope.lu.erisoft.se>
Subject: Re: UMB access with %gs selector
To: djgpp-workers AT delorie DOT com
Date: Mon, 27 Aug 2001 15:56:06 +0200 (MET DST)
In-Reply-To: <4.2.0.58.20010827140550.01b558e0@ics.u-strasbg.fr> from "Pierre Muller" at Aug 27, 2001 02:14:34 PM
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>     Doesn't this mean that the higher part of a index is not used?
> (i.e. if  $esi contain 0x10008,
> will
>     movl  %gs:(%esi),%eax
> load into %eax
> the content of linear address 0x10008 or 0x00008 ??)
> 
> Can we really access to UMB area with a 16 bit selector ?

Yes.

_All_ selectors are 16-bit of which bits 3-15 are used to index into
the GDT or LDT.


Right,

						MartinS

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