alistair23-linux/drivers/gpu
Daniel Vetter eb1711bb94 drm/i915: fix infinite recursion on unbind due to ilk vt-d w/a
The recursion loop goes retire_requests->unbind->gpu_idle->retire_reqeusts.

Every time we go through this we need a
- active object that can be retired
- and there are no other references to that object than the one from
  the active list, so that it gets unbound and freed immediately.
Otherwise the recursion stops. So the recursion is only limited by the
number of objects that fit these requirements sitting in the active list
any time retire_request is called.

Issue exercised by tests/gem_unref_active_buffers from i-g-t.

There's been a decent bikeshed discussion whether it wouldn't be
better to pass around a flag, but imo this is o.k. for such a limited
case that only supports a w/a.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42180

Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chris Wilson <chris@chris-wilson>
[ickle- we built better bikesheds, but this keeps the rain off for now]
Tested-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-12-07 10:44:40 +00:00
..
drm drm/i915: fix infinite recursion on unbind due to ilk vt-d w/a 2011-12-07 10:44:40 +00:00
stub i915: select VIDEO_OUTPUT_CONTROL for ACPI_VIDEO 2011-04-13 09:10:25 +10:00
vga drivers/gpu/vga/vgaarb.c: add missing kfree 2011-11-22 20:21:10 +00:00
Makefile gpu: Add Intel GMA500(Poulsbo) Stub Driver 2010-10-26 11:00:13 +10:00