[Linaro-mm-sig] Re: Try to address the DMA-buf coherency problem

On Tue, 22 Nov 2022 18:33:59 +0100 Christian König christian.koenig@amd.com wrote:

We should have come up with dma-heaps earlier and make it clear that exporting a DMA-buf from a device gives you something device specific which might or might not work with others.

Apart from that I agree, DMA-buf should be capable of handling this. Question left is what documentation is missing to make it clear how things are supposed to work?

Perhaps somewhat related from Daniel Stone that seems to have been forgotten: https://lore.kernel.org/dri-devel/20210905122742.86029-1-daniels@collabora.c...

It aimed mostly at userspace, but sounds to me like the coherency stuff could use a section of its own there?

Thanks, pq