Re: [PATCH] 2.6 workaround for Athlon/Opteron prefetch errata

Adrian Bunk
2003-09-12T18:25:21Z

On Fri, Sep 12, 2003 at 01:59:43PM -0400, Jeff Garzik wrote:
> Andi Kleen wrote:
> >The main reason I'm really against this is that currently the P4 kernels
> >work
> >fine on Athlon. Just when is_prefetch is not integrated in them there will
> >be an mysterious oops once every three months in the kernel in prefetch
> >on Athlon.
>
>
> Booting a P4 kernel _without_ CONFIG_X86_GENERIC on an Athlon would be a
> user bug.

But even CONFIG_X86_GENERIC doesn't do what you expect. A kernel
compiled for Athlon wouldn't run on a Pentium 4 even with
CONFIG_X86_GENERIC.

Quoting arch/i386/Kconfig in -test5:

<-- snip -->

config X86_USE_3DNOW
bool
depends on MCYRIXIII || MK7
default y

<-- snip -->

My patch in the mail

RFC: [2.6 patch] better i386 CPU selection

tries to solve these problem with a different approach (the user selects
all CPUs he wants to support).

> Jeff

cu
Adrian

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