Re: [PATCH] boot_cpu_data corruption on SMP x86

[Richard B. Johnson]

On Fri, 22 Mar 2002, Maciej W. Rozycki wrote:

> On Fri, 22 Mar 2002, Dave Jones wrote:
> 
> >  > If say the BSP supports cpuid but an AP does not (possible for an
> >  > i486 setup)
> > 
> >  It's also possible on any SMP aware system, but with the warning
> 
>  Nope, anything that provides cpuid will update the model and the stepping
> correctly.
> 
> >  "you use asymetric CPUs, you get to keep the pieces". I don't recall
> >  486's being any exception to this rule.
> 
>  Cpuid vs non-cpuid is a non-issue for the i486 -- the glue logic is
> external as well as APICs and we don't care about the SMM, so no need to
> unsupport it explicitly. 
> 

FYI, the "fix" to make Windows/2000/Professional survive more than
a day before requiring a low-level format and re-install of everything,
was to remove the second CPU from a 2 - CPU system that ran for two
years without errors under Linux. Linux may have a race-or two, but
it certainly does a very good job with SMP, something that M$ will
apparently never do.

Cheers,
Dick Johnson

Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips).

                 Windows-2000/Professional isn't.