drm/amd/display: Fail atomic_check early on normalize_zpos error

[Why]

drm_atomic_normalize_zpos() can return an error code when there's
modeset lock contention. This was being ignored.

[How]

Bail out of atomic check if normalize_zpos() returns an error.

Fixes: b261509952bc ("drm/amd/display: Fix double cursor on non-video RGB MPO")
Signed-off-by: Leo Li <sunpeng.li@amd.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 93dee3d..9c7b69d 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -9658,7 +9658,11 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
         * `dcn10_can_pipe_disable_cursor`). By now, all modified planes are in
         * atomic state, so call drm helper to normalize zpos.
         */
-       drm_atomic_normalize_zpos(dev, state);
+       ret = drm_atomic_normalize_zpos(dev, state);
+       if (ret) {
+               drm_dbg(dev, "drm_atomic_normalize_zpos() failed\n");
+               goto fail;
+       }
 
        /* Remove exiting planes if they are modified */
        for_each_oldnew_plane_in_state_reverse(state, plane, old_plane_state, new_plane_state, i) {