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From: Charles Sandmann <sandmann AT clio DOT rice DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DS and ESP
Date: Tue, 19 Feb 2002 10:24:41 CST
Organization: Rice University, Houston TX
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> That is correct. Unless interrupts are disabled when [code using
> values below ESP] executes it's extremely broken. And it might be 
> broken even if interrupts are disabled (page fault e. g.).

If the DPMI provider is done correctly either hardware interrupts or
even page faults work fine even when the user ESP is invalid.  All of
these should be handled on the locked 4Kb DPMI internal stack and
never touch the user stack.  So, it turns out that code isn't broken :-)