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Date: Mon, 7 Sep 2015 16:58:46 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Marc Zyngier <marc.zyngier@arm.com>
cc: Yang Yingliang <yangyingliang@huawei.com>,
        Jiang Liu <jiang.liu@linux.intel.com>,
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        Mark Rutland <mark.rutland@arm.com>, Will Deacon <will.deacon@arm.com>,
        Russell King - ARM Linux <linux@arm.linux.org.uk>,
        Hanjun Guo <hanjun.guo@linaro.org>
Subject: Re: [RFC PATCH v1 2/4] irqchip: GICv3: set non-percpu irqs status
 with _IRQ_MOVE_PCNTXT
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On Mon, 7 Sep 2015, Marc Zyngier wrote:
> On 07/09/15 14:24, Thomas Gleixner wrote:
> > The history of this flag is as follows:
> > 
> > On x86 interrupts can only be safely migrated while the interrupt is
> > handled.
> 
> Woa! That's creative! :-) I suppose this doesn't work very well with CPU
> hotplug though...

Go figure ....
 
> So I wonder why we bother introducing the IRQ_MOVE_PCNTXT flag on ARM at
> all. Is that just because migration.c is only compiled when
> GENERIC_PENDING_IRQ is set?

Looks like. We can distangle that, if this code needs to be reusable.

Thanks,

	tglx