Am Freitag, den 12.02.2021, 18:46 +0100 schrieb Noralf Trønnes: > +static void gud_connector_early_unregister(struct drm_connector *connector) > +{ > + struct gud_connector *gconn = to_gud_connector(connector); > + > + backlight_device_unregister(gconn->backlight); > + cancel_work_sync(&gconn->backlight_work); > +} Hi, this looks like you are creating a race condition where the queued work may operate on an already unregistered backlight. Regards Oliver