Commit 63074eed authored Apr 18, 2025 by Srinivasan Shanmugam Committed by Greg Kroah-Hartman Jun 27, 2025

drm/amd/display: Add NULL pointer checks in dm_force_atomic_commit()



[ Upstream commit 3f397cd203f247879c2f1a061e90d4c8d23655de ]

This commit updates the dm_force_atomic_commit function to replace the
usage of PTR_ERR_OR_ZERO with IS_ERR for checking error states after
retrieving the Connector (drm_atomic_get_connector_state), CRTC
(drm_atomic_get_crtc_state), and Plane (drm_atomic_get_plane_state)
states.

The function utilized PTR_ERR_OR_ZERO for error checking. However, this
approach is inappropriate in this context because the respective
functions do not return NULL; they return pointers that encode errors.

This change ensures that error pointers are properly checked using
IS_ERR before attempting to dereference.

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Cc: Tom Chung <chiahsuan.chung@amd.com>
Cc: Roman Li <roman.li@amd.com>
Cc: Alex Hung <alex.hung@amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent ceb810de

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

+12 −6

Original line number	Diff line number	Diff line
		@@ -6505,16 +6505,20 @@ static int dm_force_atomic_commit(struct drm_connector *connector)
		*/
		conn_state = drm_atomic_get_connector_state(state, connector);

		ret = PTR_ERR_OR_ZERO(conn_state);
		if (ret)
		/* Check for error in getting connector state */
		if (IS_ERR(conn_state)) {
		ret = PTR_ERR(conn_state);
		goto out;
		}

		/* Attach crtc to drm_atomic_state*/
		crtc_state = drm_atomic_get_crtc_state(state, &disconnected_acrtc->base);

		ret = PTR_ERR_OR_ZERO(crtc_state);
		if (ret)
		/* Check for error in getting crtc state */
		if (IS_ERR(crtc_state)) {
		ret = PTR_ERR(crtc_state);
		goto out;
		}

		/* force a restore */
		crtc_state->mode_changed = true;
		@@ -6522,9 +6526,11 @@ static int dm_force_atomic_commit(struct drm_connector *connector)
		/* Attach plane to drm_atomic_state */
		plane_state = drm_atomic_get_plane_state(state, plane);

		ret = PTR_ERR_OR_ZERO(plane_state);
		if (ret)
		/* Check for error in getting plane state */
		if (IS_ERR(plane_state)) {
		ret = PTR_ERR(plane_state);
		goto out;
		}

		/* Call commit internally with the state we just constructed */
		ret = drm_atomic_commit(state);