[RFC PATCH 2/3] drm/sched: Taint workqueues with reclaim

[Matthew Brost <matthew.brost@intel.com>]

Multiple drivers seemingly do not understand the role of DMA fences in
the reclaim path. As a result, DRM scheduler workqueues, which are part
of the fence signaling path, must not allocate memory. This patch
teaches lockdep to recognize these rules in order to catch driver-side
bugs.

Cc: Christian König <christian.koenig@amd.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Philipp Stanner <phasta@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/scheduler/sched_main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index c39f0245e3a9..676484dd3ea3 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -1368,6 +1368,9 @@ int drm_sched_init(struct drm_gpu_scheduler *sched, const struct drm_sched_init_
 	atomic64_set(&sched->job_id_count, 0);
 	sched->pause_submit = false;
 
+	taint_reclaim_workqueue(sched->submit_wq, GFP_KERNEL);
+	taint_reclaim_workqueue(sched->timeout_wq, GFP_KERNEL);
+
 	sched->ready = true;
 	return 0;
 Out_unroll:
-- 
2.34.1