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Subject: Re: [RFC 0/4] Virtio uses DMA API for all devices
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Will Deacon <will.deacon@arm.com>,
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Date:   Tue, 07 Aug 2018 10:18:07 +1000
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On Tue, 2018-08-07 at 02:45 +0300, Michael S. Tsirkin wrote:
> > OK well, assuming Christoph can solve the direct case in a way that
> > also work for the virtio !iommu case, we still want some bit of logic
> > somewhere that will "switch" to swiotlb based ops if the DMA mask is
> > limited.
> > 
> > You mentioned an RFC for that ? Do you happen to have a link ?
> 
> No but Christoph did I think.

Ok I missed that, sorry, I'll dig it out. Thanks.

Cheers,
Ben.