As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - FLIGHT ATTENDNANTS REPORTED VISIBLE SMOKE AND ODOR IN AFT CABIN AREA. EMERGENCY DECLARED FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED LEFT AND RIGHT PRESSURE REGULATOR VALVES AND ACCOMPLISHED HIGH PRESSURE PACK BURN. SYSTEM GROUND CHECK NORMAL OPERATION.