As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED AFTER TAKEOFF, A LAVATORY SMOKE INDICATION ON EICAS AND RECEIVED A CALL FROM THE F/A REPORTING SMOKE IN REAR SECTION OF THE CABIN AND SMOKE ALARM ACTIVATED. NO FIRE OF SMOKE SOURCE WAS FOUND BY F/A. AIR RETURN, SMOKE ODOR IN CABIN GONE AT DESCENT STARTED. ACFT WAS MET ON THE TAXI WAY AND INSPECTED THE EXTERIOR OF ACFT. NO FIRE OR SMOKE DAMAGE FOUND. ACFT REMOVED FROM SERVICE. COMPLIED WITH EM-72-034 R4. NO ODORS WERE NOTED AT THIS TIME. AIRCRAFT RETURNED TO SERVICE.