Mike Tyson was headed for expensive weed conference before airplane attack

Al Pacino’s Scarface sagely advised drug dealers never to get high on their own supply. But we wonder if Mike Tyson would actually be in less trouble if he’s toked a little of his own weed line before boarding his flight.

The heavyweight legend reportedly lost his temper with an overexcited (and possibly overserved) fan before takeoff on his flight from San Francisco to Miami on Thursday — and seemingly punched the guy several times, leaving the his head bloodied.

But The Post hears that news of the incident harshed the collective mellow at the Benzinga Cannabis Conference, because “Iron Mike” was supposed to be the main speaker at a $3000-a-ticket reception on Thursday night.