Re: [Bug][5.18-rc0] Between commits ed4643521e6a and 34af78c4e616, appears warning "WARNING: CPU: 31 PID: 51848 at drivers/dma-buf/dma-fence-array.c:191 dma_fence_array_create+0x101/0x120" and some games stopped working.

[Christian König]

Am 08.04.22 um 19:25 schrieb Mikhail Gavrilov:
> On Fri, 8 Apr 2022 at 19:27, Christian König <christian.koenig@xxxxxxx> wrote:
> > Please test the attached patch, it just re-introduce the lock without
> > doing much else.
> >
> > And does your branch contain the following patch:
> >
> > commit d18b8eadd83e3d8d63a45f9479478640dbcfca02
> > Author: Christian König <christian.koenig@xxxxxxx>
> > Date:   Wed Feb 23 14:35:31 2022 +0100
> >
> >       drm/amdgpu: install ctx entities with cmpxchg
> >
> >       Since we removed the context lock we need to make sure that not two
> > threads
> >       are trying to install an entity at the same time.
> >
> >       Signed-off-by: Christian König <christian.koenig@xxxxxxx>
> >       Fixes: 461fa7b0ac565e ("drm/amdgpu: remove ctx->lock")
> >       Reviewed-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
> >       Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
> The all listed games are now working with an attached patch.
> Also flood messages "WARNING: CPU: 31 PID: 51848 at
> drivers/dma-buf/dma-fence-array.c:191
> dma_fence_array_create+0x101/0x120" has gone.

That's unfortunately not the end of the story.

This is fixing your problem, but reintroducing the original problem that 
we call the syncobj with a lock held which can crash badly as well.

Going to take a closer look on Monday. I hope you can test a few more 
patches to help narrow down what's actually going wrong here.

Thanks,
Christian.

> Thanks.
>
> Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@xxxxxxxxx>