I am having this error since version 29 (and persist). This error occurs right after the system boot or when I disable or activate any device via modprobe, such as wireless card. However, this error with ATI/Radeon drivers does not compromise laptop usage (hybrid graphics, intel + amd). I have tested other distributions (Debian and Arch) to see if the error persists, but everything worked perfectly and without errors.
My bug report: Bugzilla ticket