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Date:   Thu, 22 Apr 2021 07:31:28 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Jason Wang <jasowang@redhat.com>
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Subject: Re: [RFC PATCH 0/7] Untrusted device support for virtio
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On Wed, Apr 21, 2021 at 11:21:10AM +0800, Jason Wang wrote:
> The behaivor for non DMA API is kept for minimizing the performance
> impact.

NAK.  Everyone should be using the DMA API in a modern world.  So
treating the DMA API path worse than the broken legacy path does not
make any sense whatsoever.