Subject: Re: Pentium Bug may cause system crash
To: Markus Illenseer <>
From: Jason Thorpe <>
List: current-users
Date: 11/08/1997 11:52:00
On Sat, 8 Nov 1997 15:58:10 +0100 (MET) 
 Markus Illenseer <> wrote:

 >  Forwared from a Linux group, are we vulnerable as well? See attached
 > source code.

It's not a software bug.  It's a hardware bug.  Yes, it appears that
certain steppings of Pentium processors have a bug that causes that
wedges the processor solid.

Seems as if some older Pentiums (i.e. old 66MHz models) aren't affected; I
sent a test program to a friend at Sequent, and it did not kill the
dual-processor Sequent system he tested it on.

I tried it on my Pentium Pro system, and it (correctly) caused an illegal
instruction fault.

Jason R. Thorpe                             
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