[Intel-gfx] [PATCH 2/2] dma-buf: Fix dma_resv_test_signaled.

[Maarten Lankhorst]

Op 15-10-2021 om 14:07 schreef Christian König:
> Am 15.10.21 um 13:57 schrieb Maarten Lankhorst:
>> Commit 7fa828cb9265 ("dma-buf: use new iterator in dma_resv_test_signaled")
>> accidentally forgot to test whether the dma-buf is actually signaled, breaking
>> pretty much everything depending on it.
>
> NAK, the dma_resv_for_each_fence_unlocked() returns only unsignaled fences. So the code is correct as it is. 

That seems like it might cause some unexpected behavior when that function is called with one of the fence locks held, if it calls dma_fence_signal().

Could it be changed to only test the signaled bit, in which case this patch would still be useful?

Or at least add some lockdep annotations, that fence->lock might be taken. So any hangs would at least be easy to spot with lockdep.

~Maarten