Re: Radeon regression in 6.6 kernel

From: Phillip Susi
Date: Wed Nov 29 2023 - 15:24:12 EST


Luben Tuikov <ltuikov89@xxxxxxxxx> writes:

> I remember that the problem was really that amdgpu called drm_sched_entity_init(),
> in amdgpu_ttm_set_buffer_funcs_status() without actually having initialized the scheduler
> used therein. For instance, the code before commit b70438004a14f4, looked like this:
>

<snip>

> sched = &ring->sched; <-- LT: No one has initialized this scheduler
> r = drm_sched_entity_init(&adev->mman.entity, <-- Oopses, now that sched->sched_rq is not

<snip>

> Before commit 56e449603f0ac5, amdgpu was getting away with this, because the sched->sched_rq
> was a static array.
>
> Ideally, amdgpu code would be fixed.

This sounds like an initilization problem that resulted in an OOPS at
boot time, but I don't remember seeing that. I just get a failure on
system suspend.