Re: Possible Pentium MMX CPU bug?

Malcolm Beattie (mbeattie@sable.ox.ac.uk)
Fri, 28 Nov 1997 16:08:03 +0000 (GMT)

Ingo Molnar writes:
> Here is the testprogram i wrote to detect the (suspected!) CPU bug. It
> outputs this on a Stepping 6 'Classic' Pentium 100 MHz:
>
> $ ./mw_bug
> testing bug ... no Pentium MMX 'missed write' bug in this CPU.
>
> and this is displayed on a Stepping 3 Pentium/MMX 200 MHz processor:
>
> $ ./mw_bug
> testing bug ... possible Pentium MMX 'missed write' CPU bug detected!

% cat /proc/cpuinfo
processor : 0
cpu : 586
model : 4
vendor_id : GenuineIntel
stepping : 4
fdiv_bug : no
hlt_bug : no
fpu : yes
fpu_exception : yes
cpuid : yes
wp : yes
flags : fpu vme de pse tsc msr mce cx8 mmx
bogomips : 298.19

% ./mw_bug
testing bug ... possible Pentium MMX 'missed write' CPU bug detected!

--Malcolm

-- 
Malcolm Beattie <mbeattie@sable.ox.ac.uk>
Unix Systems Programmer
Oxford University Computing Services