[PATCH 2/2 v2] drm/atomic: clear new_state pointers at hw_done

Rob Clark
2019-11-04T17:42:03Z

From: Rob Clark <robdclark@chromium.org>

The new state should not be accessed after this point. Clear the
pointers to make that explicit.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
drivers/gpu/drm/drm_atomic_helper.c | 30 +++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 648494c813e5..aec9759d9df2 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -2246,12 +2246,42 @@ EXPORT_SYMBOL(drm_atomic_helper_fake_vblank);
*/
void drm_atomic_helper_commit_hw_done(struct drm_atomic_state *old_state)
{
+ struct drm_connector *connector;
+ struct drm_connector_state *old_conn_state, *new_conn_state;
struct drm_crtc *crtc;
struct drm_crtc_state *old_crtc_state, *new_crtc_state;
+ struct drm_plane *plane;
+ struct drm_plane_state *old_plane_state, *new_plane_state;
struct drm_crtc_commit *commit;
+ struct drm_private_obj *obj;
+ struct drm_private_state *old_obj_state, *new_obj_state;
int i;

+ /*
+ * After this point, drivers should not access the permanent modeset
+ * state, so we also clear the new_state pointers to make this
+ * restriction explicit.
+ *
+ * For the CRTC state, we do this in the same loop where we signal
+ * hw_done, since we still need to new_crtc_state to fish out the
+ * commit.
+ */
+
+ for_each_oldnew_connector_in_state(old_state, connector, old_conn_state, new_conn_state, i) {
+ old_state->connectors[i].new_state = NULL;
+ }
+
+ for_each_oldnew_plane_in_state(old_state, plane, old_plane_state, new_plane_state, i) {
+ old_state->planes[i].new_state = NULL;
+ }
+
+ for_each_oldnew_private_obj_in_state(old_state, obj, old_obj_state, new_obj_state, i) {
+ old_state->private_objs[i].new_state = NULL;
+ }
+
for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) {
+ old_state->crtcs[i].new_state = NULL;
+
commit = new_crtc_state->commit;
if (!commit)
continue;
--
2.23.0