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Date: Fri, 30 Mar 2012 23:23:06 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Jiang Liu <liuj97@gmail.com>
cc: Jiang Liu <jiang.liu@huawei.com>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
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        x86@kernel.org, Keping Chen <chenkeping@huawei.com>,
        Tony Luck <tony.luck@intel.com>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3 3/4] IRQ,x86: normalize return value of chip->irq_set_affinity()
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On Fri, 30 Mar 2012, Jiang Liu wrote:

> On x86 platforms, interrupt controller chip's irq_set_affinity() method
> always copies affinity mask to irq_data->affinity field but still returns

Now the question here is whether it copies the mask because it
modified the mask in some way and want to reflect the change back.

If it just copies the unmodified mask, then this patch is wrong. It
should remove the copy from the arch code and return IRQ_SET_MASK_OK
so the core code can take care of the copying.

Ditto for the ia64 one.

Thanks,

	tglx