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Subject: Re: [RFC][PATCH] powerpc: respect how command line nr_cpus is set
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Kumar Gala <galak@kernel.crashing.org>
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Date: Fri, 06 May 2011 08:29:23 +1000
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> From Documentation/kernel-parameters.txt:
> 
>         nr_cpus=        [SMP] Maximum number of processors that an SMP kernel
>                         could support.  nr_cpus=n : n >= 1 limits the kernel to
>                         supporting 'n' processors. Later in runtime you can not
>                         use hotplug cpu feature to put more cpu back to online.
>                         just like you compile the kernel NR_CPUS=n
> 
> Which makes me think we should have max_cpus be an absolute limit.

Ok, looks like I've been confusing nr_cpus= vs. max_cpus= or something
like that.

I'll have a look at your patch later today.

Cheers,
Ben.