Hello Nicholas Kazlauskas,
Commit 88694af9e4d1 ("drm/amd/display: Expose HDR output metadata for
supported connectors") from May 28, 2019 (linux-next), leads to the
following Smatch static checker warning:
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:10751 dm_update_crtc_state()
warn: 'drm_new_conn_state' can also be NULL
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c
10672 static int dm_update_crtc_state(struct amdgpu_display_manager *dm,
10673 struct drm_atomic_state *state,
10674 struct drm_crtc *crtc,
10675 struct drm_crtc_state *old_crtc_state,
10676 struct drm_crtc_state *new_crtc_state,
10677 bool enable,
10678 bool *lock_and_validation_needed)
10679 {
10680 struct dm_atomic_state *dm_state = NULL;
10681 struct dm_crtc_state *dm_old_crtc_state, *dm_new_crtc_state;
10682 struct dc_stream_state *new_stream;
10683 int ret = 0;
10684
10685 /*
10686 * TODO Move this code into dm_crtc_atomic_check once we get rid of dc_validation_set
10687 * update changed items
10688 */
10689 struct amdgpu_crtc *acrtc = NULL;
10690 struct drm_connector *connector = NULL;
10691 struct amdgpu_dm_connector *aconnector = NULL;
10692 struct drm_connector_state *drm_new_conn_state = NULL, *drm_old_conn_state = NULL;
10693 struct dm_connector_state *dm_new_conn_state = NULL, *dm_old_conn_state = NULL;
10694
10695 new_stream = NULL;
10696
10697 dm_old_crtc_state = to_dm_crtc_state(old_crtc_state);
10698 dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
10699 acrtc = to_amdgpu_crtc(crtc);
10700 connector = amdgpu_dm_find_first_crtc_matching_connector(state, crtc);
10701 if (connector)
10702 aconnector = to_amdgpu_dm_connector(connector);
10703
10704 /* TODO This hack should go away */
10705 if (connector && enable) {
10706 /* Make sure fake sink is created in plug-in scenario */
10707 drm_new_conn_state = drm_atomic_get_new_connector_state(state,
10708 connector);
drm_atomic_get_new_connector_state() can't return error pointers, only
NULL.
10709 drm_old_conn_state = drm_atomic_get_old_connector_state(state,
10710 connector);
10711
10712 if (IS_ERR(drm_new_conn_state)) {
^^^^^^^^^^^^^^^^^^
10713 ret = PTR_ERR_OR_ZERO(drm_new_conn_state);
Calling PTR_ERR_OR_ZERO() doesn't make sense. It can't be success.
10714 goto fail;
10715 }
10716
10717 dm_new_conn_state = to_dm_connector_state(drm_new_conn_state);
10718 dm_old_conn_state = to_dm_connector_state(drm_old_conn_state);
10719
10720 if (!drm_atomic_crtc_needs_modeset(new_crtc_state))
10721 goto skip_modeset;
10722
10723 new_stream = create_validate_stream_for_sink(connector,
10724 &new_crtc_state->mode,
10725 dm_new_conn_state,
10726 dm_old_crtc_state->stream);
10727
10728 /*
10729 * we can have no stream on ACTION_SET if a display
10730 * was disconnected during S3, in this case it is not an
10731 * error, the OS will be updated after detection, and
10732 * will do the right thing on next atomic commit
10733 */
10734
10735 if (!new_stream) {
10736 DRM_DEBUG_DRIVER("%s: Failed to create new stream for crtc %d\n",
10737 __func__, acrtc->base.base.id);
10738 ret = -ENOMEM;
10739 goto fail;
10740 }
10741
10742 /*
10743 * TODO: Check VSDB bits to decide whether this should
10744 * be enabled or not.
10745 */
10746 new_stream->triggered_crtc_reset.enabled =
10747 dm->force_timing_sync;
10748
10749 dm_new_crtc_state->abm_level = dm_new_conn_state->abm_level;
10750
--> 10751 ret = fill_hdr_info_packet(drm_new_conn_state,
^^^^^^^^^^^^^^^^^^
Unchecked dereference
10752 &new_stream->hdr_static_metadata);
10753 if (ret)
10754 goto fail;
10755
regards,
dan carpenter
