As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLIGHT 2928, THE CREW REPORTED SMOKE IN THE CABIN DURING CLIMB. THE AIRCRAFT RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE RIGHT HAND PACK CONTROL VALVE, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.