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Date: Wed, 5 Oct 2011 21:25:14 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Fenghua Yu <fenghua.yu@intel.com>
cc: Ingo Molnar <mingo@elte.hu>, H Peter Anvin <hpa@zytor.com>,
        Zwane Mwaikambo <zwane@arm.linux.org.uk>,
        Tony Luck <tony.luck@intel.com>,
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        Suresh B Siddha <suresh.b.siddha@intel.com>,
        Len Brown <lenb@kernel.org>,
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Subject: Re: [PATCH 8/8] kernel/cpu.c: Define bsp_hotpluggable variable
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On Wed, 5 Oct 2011, Fenghua Yu wrote:

> From: Fenghua Yu <fenghua.yu@intel.com>
> 
> This gloable variable controls BSP (aka CPU0) hotplug. If set, BSP is
> hotpluggable. By default, it's 0. On X86, kernel option bsp_hotpluggable sets
> the variable as 1.

.... and on !x86 its just pointless.
 
I have yet to see a justification for that whole cpu0 unplugging
business.

If there is a real reason that this is desireable, then ALL cpu0
assumptions in arch/x86 need to be cleaned up and fixed.

Thanks,

	tglx