As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A FLIGHT ATTENDANT REPORTED SMOKE ENTERED THE CABIN JUST AFTER TAKEOFF FROM DEN. THE SMOKE SOURCE WAS ISOLATED TO AIR CONDITIONING PACKS AND THE AIRCRAFT WAS RETURNED TO DEN. MAIINTENANCE FOUND THE APU WAS BLOWING OIL UP THROUGH PLENUM INTO THE AIR SYSTEM. THE APU WAS REMOVED AND REPLACED PER MM 49-10-00. LEAK AND OPERATIONAL CHECKS WERE GOOD. PART TOTAL CYCLES, 11,261.