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Date:	Mon, 10 Dec 2001 21:26:09 +0200
From:	"Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
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To:	sandmann AT clio DOT rice DOT edu
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Subject:	Re: go32-v2 memory chompage [was: Re: v2.03 refresh ...]
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> From: sandmann AT clio DOT rice DOT edu (Charles Sandmann)
> Date: Mon, 10 Dec 2001 12:41:06 -0600 (CST)
> 
> go32-v2 allocates dos memory to pass the command line
> v2load allocates dos memory for the environment and command line
> v2load allocates dos memory for the transfer buffer
> 
> (I think this explains the 3 sizes of blocks observed).

Yes.  Sorry, I should have remembered that, as I wrote most of that
stuff.

> Now, we pass the child a stubinfo psp returned from a dos memory block
> allocation... but it doesn't look like a valid DPMI psp selector to me.

So, are you saying that the W2K DPMI host returns a bogus selector
when we allocate DOS memory?  Another W2K bug? ;-)

> We let the child "exit" back to us.  During that exit the child passes 
> this bogus psp to NT as a set psp - what happens?  Then the child may 
> do some operations to NTVDM/DPMI with an invalid psp?

I think the ``exit back to us'' part needs closer scrutiny.  IIRC,
the way  a child program invoked via v2load exits is different from a
normal nesting via dosexec.  Sorry, I forget the details, and don't
have time to look them up, but perhaps the comments in go32-v2.c's
`main' function will help.

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