Date: Mon, 13 Dec 1999 10:37:49 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender: eliz AT is
To: Pierre Muller <muller AT cerbere DOT u-strasbg DOT fr>
cc: Peter Johnson <locke AT mcs DOT net>, djgpp AT delorie DOT com
Subject: Re: NT4 DPMI BUG (303h, Allocate Real-Mode Callback)
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On Sun, 12 Dec 1999 muller AT cerbere DOT u-strasbg DOT fr wrote:

>   I mean that I only reserved room for one such structure inside
> the loader file (equivalent of crt0.S)
> so all calls to 0x303 DPMI function must use the same 
> register struct !
> (But Ralph Brown interrupt list anyhow states
> that the content of this struct should only be
> examined inside the protected mode code itself !)
> 
>  So if you specify another struct defined elsewhere 
> it will probably have an address > 0x10000 and thus WinNT
> will write data at a wrong address ( true addr & 0xffff !!)
> => crash !

Sorry, I'm still confused.  AFAIK, Peter's solution doesn't call for
another struct, it just passes to NT a different selector and offset
for the same linear address of the same struct.  The segment whose
selector is passed is arranged in such a way that the offset has its
high 16 bits cleared.