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Date:   Tue, 15 Jun 2021 15:40:32 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Claire Chang <tientzu@chromium.org>
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Subject: Re: [PATCH v10 09/12] swiotlb: Add restricted DMA pool
 initialization
Message-ID: <20210615134032.GI20389@lst.de>
References: <20210615132711.553451-1-tientzu@chromium.org> <20210615132711.553451-10-tientzu@chromium.org>
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On Tue, Jun 15, 2021 at 09:27:08PM +0800, Claire Chang wrote:
> Add the initialization function to create restricted DMA pools from
> matching reserved-memory nodes.
> 
> Regardless of swiotlb setting, the restricted DMA pool is preferred if
> available.
> 
> The restricted DMA pools provide a basic level of protection against the
> DMA overwriting buffer contents at unexpected times. However, to protect
> against general data leakage and system memory corruption, the system
> needs to provide a way to lock down the memory access, e.g., MPU.
> 
> Signed-off-by: Claire Chang <tientzu@chromium.org>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>