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Date: Thu, 28 Sep 2017 11:18:46 +0800
From: jeffy <jeffy.chen@rock-chips.com>
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To: Thomas Gleixner <tglx@linutronix.de>
CC: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] irq/generic-chip: Fix memory leak of domain->name
References: <20170927122816.18931-1-jeffy.chen@rock-chips.com> <alpine.DEB.2.20.1709271521060.2027@nanos>
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Hi Thomas,

Thanks for your review.

On 09/27/2017 09:29 PM, Thomas Gleixner wrote:
> On Wed, 27 Sep 2017, Jeffy Chen wrote:
>
>> Free domain->name when IRQ_DOMAIN_NAME_ALLOCATED been set.
>
> I can see that from the patch, but you fail to explain what the problem
> is.
>
> It's actually more than just a memory leak. If the domain gets destroyed
> then the domain free code would try to free d->name which might be a string
> constant .....
ok, i'll add that to commit msg.
>
>> +	if (d->flags & IRQ_DOMAIN_NAME_ALLOCATED) {
>> +		kfree(d->name);
>> +		d->flags &= ~IRQ_DOMAIN_NAME_ALLOCATED;
>> +	}
>>   	d->name = name;
>
> I don't think that this is the proper thing to do. There is no reason why
> the domain should have the same name as the irq chip. So we rather should
> do:
>
> 	if (!d->name)
> 		d->name = name;
>
> Along with a proper comment.
that is better, will do it in next version :)
>
> Thanks,
>
> 	tglx
>
>
>
>