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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] moxa: drop free_irq of devm_request_irq allocated irq
Date: Mon, 30 Sep 2013 14:55:26 -0400 (EDT)
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From: Wei Yongjun <weiyj.lk@gmail.com>
Date: Wed, 25 Sep 2013 15:33:29 +0800

> From: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
> 
> irq allocated with devm_request_irq should not be freed using
> free_irq, because doing so causes a dangling pointer, and a
> subsequent double free.
> 
> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>

I think this is a dangerous change, if the IRQ fires after the point
of the existing free_irq() call it will try to dereference the net
device struct which will be free by the time the devm release code
runes.

I'm not applying this patch, sorry.