Date: Sun, 29 Jun 2003 06:15:38 +0300
From: "Eli Zaretskii" <eliz AT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: michael AT idisys DOT iae DOT nsk DOT su
Message-Id: <2561-Sun29Jun2003061537+0300-eliz@elta.co.il>
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CC: djgpp AT delorie DOT com
In-reply-to: <Pine.LNX.4.53L.0306281651030.1756@idisys.iae.nsk.su>
	(michael AT idisys DOT iae DOT nsk DOT su)
Subject: Re: Crash: CWSDSTUB vs PMODSTUB
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> Date: Sat, 28 Jun 2003 17:30:30 +0700 (NOVST)
> From: michael AT idisys DOT iae DOT nsk DOT su
> 
> I have one program that works with ASPI devices, recently I replaced
> PMODSTUB v1.3 with CWSDSTUB v5 and already received many reports
> about strange behavior when working with bad ZIP discs. I was able to
> recreate one typical situation: IOMEGA ZIP with native
> drivers (any version from 3 to 6), if ZIP drive is corrupt (scratched
> with a razor), then instead of reporting read error system hangs,
> gives GPF or just prints garbage on the screen. It happens only
> if I use CWSDPMI (not only stub), the same COFF with
> attached PMODSTUB works fine. Obviously it not "NULL pointer assignment"
> or something what CWSDPMI intercepts unlike PMODE.

Can you explain why you are so confident it's not a NULL pointer
dereference?

Anyway, if you can reproduce the situation where it GPFaults, please
post here the full text of the message it prints when it crashes,
complete with the registers dump and traceback (after SYMIFY).  That
information can help us point you to the possible causes for the
problem.