3.18-rc regression: drm/nouveau: use shared fences for readable objects

[Ian Kumlien]

Hi,

Sorry to but in like this but I'm suffering from the same kind of
deadlocks with nouveau...

The really odd thing is that i could boot some -rc6+ kernel without
problems but it hung
while playing video and then it refused to start properly again.


Anyway, to quote Maarten:
Ok that most likely means the interrupt based wait is borked somehow,
so lets find \
out why..

I fear that this happens because of a race in the interface, so my
first attempt will \
rule out abuse of the nvif api by nouveau_fence.c

Can you test below patch with the default wait function?
---

I tried the patch, straight on Linus' master and it didn't change
anything for me :(