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Date: Tue, 5 Sep 2017 09:15:40 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: "Huang, Ying" <ying.huang@intel.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] IRQ, cpu-hotplug: Fix a race between CPU hotplug and
 IRQ desc alloc/free
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On Tue, 5 Sep 2017, Huang, Ying wrote:
> Thomas Gleixner <tglx@linutronix.de> writes:
> > +	/* Interrupts are moved away from the dying cpu, reenable alloc/free */
> > +	irq_unlock_sparse();
> > +
> 
> I don't understand this.  It appears that irq_migrate_all_off_this_cpu()
> is called in take_cpu_down() which has sparse_irq_lock held already.

You're right. I was looking at the wrong place.

Thanks,

	tglx