IIRC, Rock referenced Jada (who is bald due to alopecia) before dropping the "GI Jane 2" punchline. Demi Moore famously shaved her head for her role in GI Jane, and there is no sequel in the works, so it was clearly a jab at Jada. Now, Smith's reaction to the whole thing was way over the line. It was a joke, maybe an ill-timed and tasteless one, but a joke nonetheless. You can't use one of the most famous stages on the planet to dish out 'hood justice; that might have been "perfectly acceptable" had he waited until after the show, and caught Rock in his dressing room or the back alley to slap the taste out of his mouth. His point would have been made, none of us would have known, and neither of them would ever speak of it ever again. 'Hood justice.