Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!att!cbnewsh!twb
From: twb@cbnewsh.att.com (thomas.w.beattie)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: v09i191: popadbug, test for 386 CPU bug (part 01/01)
Summary: What is a POPAD?
Keywords: bug, 386, test, hardware
Message-ID: <1991Jan3.185115.10326@cbnewsh.att.com>
Date: 3 Jan 91 18:51:15 GMT
References: <2804@sixhub.UUCP>
Distribution: usa
Organization: AT&T Bell Laboratories
Lines: 23

In article <2804@sixhub.UUCP>, ibmbin-request@crdgw1.crd.ge.com writes:
>   This postings is a test program for a bug in the 386 processor. It
> seems potentially serious. 
> 
> The submitter w8sdz@tacom-emh1.army.mil says:
> 
> It seems that a new bug in some 386 processors has been discovered. 
> Mine failed the test and the system acted weird after running the
> program.  I think the bug messed up the stack or something.  Everything
> was ok again after I rebooted.  I'm not real happy about having a
> defective processor, Bill.  You may wish to tell your 386 mailing list
> about this bug.  It looks serious. 

I tried this test on two 386 machines from different manufacturers and both
failed.  One is a 386DX/16, the other a 386DX/25, both double sigmas.
The machines seem to work just fine however.

What exactly is the bug?
What kind of "potentially serious" problems are expected?
---
Tom Beattie
att!hoqaa!twb
t.w.beattie@att.com