Re: [PATCH] [20/82] i386: Panic the system when a NUMA kernel doesn't run on IBM NUMA

[Andi Kleen <ak@suse.de>]

On Saturday 24 June 2006 02:38, Dave Jones wrote:
> On Sat, Jun 24, 2006 at 02:19:28AM +0200, Andi Kleen wrote:
> 
> 
>  > +	extern int use_cyclone;
>  > +	if (use_cyclone == 0) {
>  > +		/* Make sure user sees something */
>  > +		static const char s[] __initdata = "Not an IBM x440/NUMAQ. Don't use i386 CONFIG_NUMA anywhere else.";
>  > +		early_printk(s);
>  > +		panic(s);
>  > +	}
> 
> non-IBM Machines do still boot with that enabled though don't they?


No they don't - as they likely didn't do before. e.g. Opterons generally
break and that brings the point across clearer.

The rationale is that CONFIG_NUMA is very rarely used on i386 (even on summit)
and always does bitrot quickly. It also doesn't work at all on a wide
range of machines.

I'm sure someone will bring up now an example where their non Summit 
machine booted with CONFIG_NUMA, but they were just extremly lucky
and unlikely to be for very long.

-Andi