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Subject: Re: [PATCH] ARM: dma-mapping: always clear allocated buffers
To:     Christoph Hellwig <hch@infradead.org>
References: <20180724140435.17112-1-yuehaibing@huawei.com>
 <20180724180906.GA8240@infradead.org>
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From:   YueHaibing <yuehaibing@huawei.com>
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Date:   Wed, 25 Jul 2018 10:24:07 +0800
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On 2018/7/25 2:09, Christoph Hellwig wrote:
> On Tue, Jul 24, 2018 at 10:04:35PM +0800, YueHaibing wrote:
>> Sean Wang report dma_zalloc_coherent doesn't work as expect on his
>> armv7,the allocated mem is not zeroed.The reason is __alloc_from_pool
>> doesn't honor __GFP_ZERO.
> 
> Please explain the "why" a little more.  All the explanations are in
> the referenced arm64 commit and should be mentioned here as well.

ok, will send v2.

> 
> .
>