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Date: Tue, 24 Apr 2018 23:43:35 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Daniel Vetter <daniel@ffwll.ch>
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Subject: Re: [Linaro-mm-sig] [PATCH 4/8] dma-buf: add peer2peer flag
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On Wed, Apr 25, 2018 at 08:23:15AM +0200, Daniel Vetter wrote:
> For more fun:
> 
> https://www.spinics.net/lists/dri-devel/msg173630.html
> 
> Yeah, sometimes we want to disable the iommu because the on-gpu
> pagetables are faster ...

I am not on this list, but remote NAK from here.  This needs an
API from the iommu/dma-mapping code.  Drivers have no business poking
into these details.

Thierry, please resend this with at least the iommu list and
linux-arm-kernel in Cc to have a proper discussion on the right API.