On 2/3/21 4:29 PM, Daniel Vetter wrote:
Recently there was a fairly long thread about recoreable hardware page faults, how they can deadlock, and what to do about that. While the discussion is still fresh I figured good time to try and document the conclusions a bit. This documentation section explains what's the potential problem, and the remedies we've discussed, roughly ordered from best to worst. v2: Linus -> Linux typoe (Dave) v3: - Make it clear drivers only need to implement one option (Christian) - Make it clearer that implicit sync is out the window with exclusive fences (Christian) - Add the fairly theoretical option of segementing the memory (either statically or through dynamic checks at runtime for which piece of memory is managed how) and explain why it's not a great idea (Felix) References: https://lore.kernel.org/dri-devel/20210107030127.20393-1-Felix.Kuehling@xxxxxxx/ Cc: Dave Airlie <airlied@xxxxxxxxx> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> Cc: Thomas Hellström <thomas.hellstrom@xxxxxxxxx> Cc: "Christian König" <christian.koenig@xxxxxxx> Cc: Jerome Glisse <jglisse@xxxxxxxxxx> Cc: Felix Kuehling <felix.kuehling@xxxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx> Cc: linux-media@xxxxxxxxxxxxxxx Cc: linaro-mm-sig@xxxxxxxxxxxxxxxx --- Documentation/driver-api/dma-buf.rst | 76 ++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+)
Acked-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
