If a user mode driver is changed to rely on the existence of implicit sync,
it results in corruption and flickering as reported here:
https://gitlab.freedesktop.org/mesa/mesa/-/issues/2950

Marek

On Mon, May 25, 2020 at 6:05 PM Marek Olšák <maraeo@gmail.com> wrote:

> Hi Christian,
>
> Bas and Michel wanted to discuss this. The main disadvantage of no
> implicit (pipeline) sync within the same queue is that we get lower
> performance and lower GPU utilization in some cases.
>
> We actually never really needed the kernel to have implicit sync, because
> all user mode drivers contained hacks to work without it.
>
> Marek
>