On Thu, Jan 29, 2026 at 07:06:37AM +0000, Tian, Kevin wrote:

Bear me if it's an ignorant question.

The commit msg of patch6 says that VFIO doesn't tolerate unbounded wait, which is the reason behind the 2nd timeout wait here.

As far as I understand dmabuf design a fence wait should complete eventually under kernel control, because these sleeps are sprinkled all around the kernel today.

I suspect that is not actually true for every HW, probably something like "shader programs can run forever technically".

We can argue if those cases should not report revocable either, but at least this will work "correctly" even if it takes a huge amount of time.

I wouldn't mind seeing a shorter timeout and print on the fence too just in case.

Jason