As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW INFLIGHT T1119/02FEB RECEIVED PRESSURE FLOW INDICATION FOLLOWED BY REPORT FROM FLIGHT ATTENDANTS OF SMELL AND HAZE IN MAIN CABIN AREA. RETURNED TO DFW AND LANDED WITHOUT INCIDENT. REPLACED LEFT PACK REGULATORY SHUT OFF VALVE AND ACCOMPLISHED PACK BURN. SYSTEM GROUND CHECKED NORMAL OPERATION.