Re: [PATCH] IRQ, cpu-hotplug: Fix a race between CPU hotplug and IRQ desc alloc/free

[Thomas Gleixner]

On Tue, 5 Sep 2017, Huang, Ying wrote:
> Thomas Gleixner <tglx@xxxxxxxxxxxxx> 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