I just got a random Firefox freeze with all three above patches applied. So
it's clearly not fixed yet (though such hangs are a lot less common than before
now):

[78836.138723] [drm:amdgpu_dm_atomic_commit_tail [amdgpu]] *ERROR* Waiting for
fences timed out!
[78841.770422] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring sdma1 timeout,
signaled seq=133096, emitted seq=133098
[78841.770490] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* Process information:
process GPU Process pid 1882 thread firefox-bi:cs0 pid 2034
[78841.770493] [drm] GPU recovery disabled.