Re: Loading Pentium III microcode under Linux - catch 22!

[mru@users.sourceforge.net (Måns Rullgård)]

Chris Rankin <rankincj@yahoo.com> writes:

> I have an i840 motherboard with a pair of 933 MHz PIII
> Coppermine CPUs, and I use your microcode driver to
> load the latest Intel microcode into my CPUs. This is
> very important because these CPUs are buggy without
> their microcode, and I would prefer to have the BIOS
> load it except that this would prevent me from booting
> into memtest. I have tried this before - memtest
> crashes with an "Unexpected Interrupt" error after a
> few minutes. (No i840 workarounds enabled?) Since I
> suspect that DOS would do the same thing and I would
> boot into DOS to flash firmware, I have decided that
> crashes like this would be a Bad Thing.

If the microcode in the CPUs is buggy, they are faulty and you should
demand to get them replaced at no cost.

> In an ideal world, I would like Linux to load the
> microcode *before* the kernel boots, which begs the
> question of "How?". Can you suggest anything, please?
> I remember talk of boot-time RAM disks, and wondered
> if the microcode could be placed on one of these
> somehow? Or would that be ruled out immediately by the
> microcode's non-GPL nature?

I guess it would be possible to compile the microcode into the kernel
and have some code in arch/i386/* load it as early as possible.  As
long as you don't distribute the compiled kernel you should be fine
wrt licensing.

-- 
Måns Rullgård
mru@users.sf.net