Green’s Dictionary of Slang

1. (Aus.) a scolding, a reprimand.

1985		R.G. Barrett You Wouldn’t Be Dead for Quids (1989) 159: Not to mention the frightful bagging Billy Dunne had given him when he called round for a drink.
2003		McGill Reed Dict. of N.Z. Sl.
2005		M.B. ‘Chopper’ Read Chopper 4 225: The former Victorian State Coroner [...] has given the Victoria Police a bit of a bagging over the police shootings.

2. teasing.

1992		R.G. Barrett Davo’s Little Something 25: Despite the bagging he’d been getting all afternoon [...] Davo was in a pretty good mood.
1992		M. Coleman Fatty 228: ‘It was one of the great bagging sessions’.