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Message-ID: <1331546307.18960.26.camel@twins>
Subject: Re: [PATCH] Fix the race between smp_call_function and CPU booting
From: Peter Zijlstra <peterz@infradead.org>
To: "Liu, Chuansheng" <chuansheng.liu@intel.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Yanmin Zhang <yanmin_zhang@linux.intel.com>,
        "tglx@linutronix.de" <tglx@linutronix.de>
Date: Mon, 12 Mar 2012 10:58:27 +0100
In-Reply-To: <27240C0AC20F114CBF8149A2696CBE4A053BE8@SHSMSX101.ccr.corp.intel.com>
References: <27240C0AC20F114CBF8149A2696CBE4A053BE8@SHSMSX101.ccr.corp.intel.com>
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On Mon, 2012-03-12 at 09:27 +0000, Liu, Chuansheng wrote:
> The solution is just to send smp call to active cpus instead of online
> cpus.

BTW, that solution is broken because !active cpus can still be online
and actually running stuff, so sending IPIs to them is perfectly fine
and actually required.