Re: [PATCH] Mutilated form of Andi Kleen's AMD prefetch errata patch

Andi Kleen
2003-09-30T19:08:12Z

Dave Jones <davej@redhat.com> writes:
>
> > Anyway, it should complain about lack of cmov not crash :)
>
> not easy, given we execute cmov instructions before we even hit
> a printk. Such a test & output needs to be done in assembly in early
> startup.

I implemented it for long mode on x86-64.

It has to be done before the vesafb is initialized too, otherwise
you cannot see the error message.

You could copy the code from arch/x86_64/boot/setup.S
(starting with /* check for long mode. */) and change it to
check for the CPUID bits you want. x86-64 checks a basic collection
that has been determined to be the base set of x86-64 supporting CPUs.
But it could be less or more.

-Andi