[PATCH v2 0/2] Fix nouveau-related freezes

[Andy Lutomirski <luto@MIT.EDU>]

Nouveau takes down my system quite reliably when any hotplug event occurs.
The bug happens because the IRQ handler didn't acknowledge the hotplug
state until the bottom half, so the card generated a new interrupt
immediately, starving the bottom half and permanently starving that CPU
(and hence the bottom half).

Even with this fix, a lot of the IRQ code looks rather broken.

This is tested on 2.6.36 (and makes the system stable for me), but it also
applies cleanly to 2.6.37 (untested, but surely also necessary).  Fedora 14's
2.6.35 kernels seem to have to same problem for me, so I suspect that 2.6.35
needs this fix as well.  (All of my tests are on an NV50 card.)

Changes from v1:
 - Ignore unrequested hotplug bits (I accidentally removed that part).
 - Support newer hardware (untested -- Ben, can you check this?)

Andy Lutomirski (2):
  Use existing defines for NV50 hotplug registers
  nouveau: Acknowledge HPD irq in handler, not bottom half

 drivers/gpu/drm/nouveau/nouveau_drv.h  |    6 +++++
 drivers/gpu/drm/nouveau/nouveau_irq.c  |    1 +
 drivers/gpu/drm/nouveau/nv50_display.c |   39 +++++++++++++++++++++++---------
 3 files changed, 35 insertions(+), 11 deletions(-)

-- 
1.7.3.2