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From: Andi Kleen <andi@firstfloor.org>
To: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Gilad Ben Yossef <giladb@ezchip.com>, Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <peterz@infradead.org>,
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        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andy Lutomirski <luto@amacapital.net>, <linux-doc@vger.kernel.org>,
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Subject: Re: [PATCH v10 05/12] task_isolation: support CONFIG_TASK_ISOLATION_ALL
References: <1456949376-4910-1-git-send-email-cmetcalf@ezchip.com>
	<1456949376-4910-6-git-send-email-cmetcalf@ezchip.com>
Date: Thu, 03 Mar 2016 10:34:16 -0800
In-Reply-To: <1456949376-4910-6-git-send-email-cmetcalf@ezchip.com> (Chris
	Metcalf's message of "Wed, 2 Mar 2016 15:09:29 -0500")
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Chris Metcalf <cmetcalf@ezchip.com> writes:
>  
> +config TASK_ISOLATION_ALL
> +	bool "Provide task isolation on all CPUs by default (except CPU 0)"
> +	depends on TASK_ISOLATION
> +	help
> +	 If the user doesn't pass the task_isolation boot option to
> +	 define the range of task isolation CPUs, consider that all
> +	 CPUs in the system are task isolation by default.
> +	 Note the boot CPU will still be kept outside the range to
> +	 handle timekeeping duty, etc.

That seems like a very dangerous Kconfig option.
"CONFIG_BREAK_EVERYTHING"
If someone sets that by default they will have a lot of trouble.

I wouldn't add that, make it a run time option only.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only