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Mail Archives: djgpp/2000/01/13/21:27:10

Date: Fri, 14 Jan 2000 07:52:45 +0500 (MVT)
From: Prashant TR <prashant_tr AT yahoo DOT com>
To: Martin Stromberg <Martin DOT Stromberg AT lu DOT erisoft DOT se>
cc: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>, DJGPP <djgpp AT delorie DOT com>
Subject: Re: Problems with protected_mode_int
In-Reply-To: <200001131558.QAA14542@spica-144.lu.erisoft.se>
Message-ID: <Pine.LNX.4.10.10001140746070.522-100000@yahoo.com>
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On Thu, 13 Jan 100, Martin Stromberg wrote:

> > This will most probably crash, for several good reasons:
> > 
> >   - stack is allocated off the DS selector whose access rights forbid 
> >     executing any address accessed via that selector;
> > 
> >   - the only segment register that is guaranteed to be loaded with the 
> >     application's selector is CS, so you cannot trust SS.
> 
> If no, it should work (note that at entry to the interrupt hander CS
> _is_ valid and that is what counts). Please explain more clearly why
> not.

I guess you're thinking that it's only the offset of the handler which
matters. This is not true. Both the selector and the offset combination is
necessary.

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