Re: logical, linear, physical addresses

[Lukas Ruf <ruf@xxxxxxxxx>]

> aq <aquynh@xxxxxxxxx> [2004-11-06 16:19]:
>
> hello,
>
> I think there is one question of Kannan unanswered: CS has attribute
> of "READ-ONLY", and DS has attribute of "READ-WRITE". And we all know
> that CS and DS point to the same address range (they have the same
> base address of 0, and same size of 4GB). So they overlap, but how can
> we still write data in DS segment? Writing to DS, so we write to CS,
> but CS is READ-ONLY, so the problem would occur, right ??
>

the issue is, "how you write data".  usually DS is used for that (if
you do not explicitely state the 'data'-segment register).  Of course,
you could write something like cs:.... which would explicitely make
use of the CS -- and, hence, fail.  However, ds:.... is used
implicetely if not specified other.  Ok?

wbr,
Lukas
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