Re: 2.1.80 no-go

Linus Torvalds (
Wed, 21 Jan 1998 11:57:40 -0800 (PST)

On Wed, 21 Jan 1998, Erik Andersen wrote:
> Umm. How about we make CONFIG_SMP a config option, and make a new
> CONFIG_IO-APIC_SMP config option as well. After all, we now have the nice
> new smart-config in the kernel, which means the reason CONFIG_SMP was
> moved to a Makefile is no longer an issue. I believe all the
> pre-conditions you previosly listed for changing this back are now in
> place. I believe that Michael Elizabeth Chastain <> has
> already written such a patch that works within the new smart-config
> stuff. Linus, any chance of seeing this change soon?

I can certainly make CONFIG_SMP an option these days assuming that it
really does work. That doesn't help with the IO-APIC, though: the problem
is that even on machines that _do_ want to use the IO-APIC it often has to
be set up some way that the kernel currently doesn't know how to do.

So regardless of any other issues it does begin to seem that the kernel
has to boot up "APIC-less", and the IO-APIC has to be set up at run-time
later on. And if that is true, then the IO-APIC is no longer an issue for
system config anyway..