v2: Rebase onto the new object create refcount fix patch.
v3: Don't kill dev_priv->mm.object_memory as requested by Chris and
hence just use a spinlock instead of atomic_t.
Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67287 Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>