Re: [PATCH] drm/amdgpu: Harden against potential deadlock

[Philipp Stanner <phasta@mailbox.org>]

On Tue, 2026-10-27 at 12:51 +0100, Christian König wrote:
> On 10/26/26 19:31, Felix Kuehling wrote:
> > We don't implement ops->signaled, and we explicitly signal the
> > fence from SW with dma_fence_signal or dma_fence_check_and_signal.
> > So the signaled flag should be the only thing that needs to be
> > checked. The flag is only set while holding the fence lock, and
> > checked while holding the fence lock. So in theory, relying on the
> > check in __dma_fence_enable_signaling should be safe.
> 
> I actually had a patch to remove that one send out month ago already,
> it was just never merged.
> 
> The call absolutely doesn't make sense since the ops->signaled
> callback isn't implemented and the bit tested before the enable
> signaling callback called.
> 
> I can take care and push the removal to amd-staging-drm-next when I
> find time.


OK, but put me on Cc please. I could need that change for my other
dma_fence-ish work. I would post the removal as a v2, too, if I don't
hear from you mid-term

Greetings,
Philipp