From owner-freebsd-hackers  Fri Nov  7 12:44:50 1997
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From: Kenny Hanson <khanson@pdspc.com>
To: "FreeBSD Hackers (E-mail)" <freebsd-hackers@FreeBSD.ORG>
Subject: RE: Newest Pentium bug (fatal)
Date: Fri, 7 Nov 1997 14:45:00 -0600
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This is kind of sick, but I compiled this code on a 233MMX under Win95
(I don't have a FBSD box running with a 233) and sure enough!  Locked
solid!!!

Hmmm....



> -----Original Message-----
> From:	Jon Trulson [SMTP:jon@XiG.com]
> Sent:	Friday, November 07, 1997 1:41 PM
> To:	Julian Elischer
> Cc:	hackers@FreeBSD.ORG
> Subject:	Re: Newest Pentium bug (fatal)
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> CPU: Pentium (89.81-MHz 586-class CPU)
>   Origin = "GenuineIntel"  Id = 0x524  Stepping=4
>   Features=0x1bf<FPU,VME,DE,PSE,TSC,MSR,MCE,CX8>On Fri, 7 Nov 1997,
> Julian Elischer wrote:
> 
> > Date: Fri, 07 Nov 1997 10:39:24 -0800
> > From: Julian Elischer <julian@whistle.com>
> > To: hackers@FreeBSD.ORG
> > Subject: Newest Pentium bug (fatal)
> >
> > On a "genuine Intel" pentium (not pentium pro)
> > execution of the following sequence, 0xf0 0x0f 0xc7 0xc8
> >
> > will stop the processor. This is doable from user mode and in
> > 16bitmode, or in fact any mode.
> >
> > try the following c program.
> >
> > unsigned char x[] = { 0xfo, 0x0f, 0xc7, 0xc8 };
> >
> >
> > main ()
> > {
> >   void (*f)(void) = x;
> >   f();
> > }
> >
> 
> 	Ouch.  Kills every p5 (in user mode no-less) I've tried it on...
> 
> --
> Jon Trulson    work: mailto:jon@xig.com, home: mailto:jon@radscan.com
> Xi Graphics,   http://www.xig.com
> ID: 1A9A2B09, FP: C23F328A721264E7 B6188192EC733962
> PGP keys at finger:trulson@shell.rmi.net or http://home.rmi.net/~jon
> #include <stddisclaimer.h>
> FREE MARS!
>