Details have begun to trickle out about Like A Stone, a semi-documentary about the life and career of late Soundgarden singer Chris Cornell. According to IMDB.com, producers on the film include Brad Pitt and Cornell's widow Vicky, while the director will be Peter Berg, the filmmaker behind movies like Lone Survivor, Patriots Day and Deepwater Horizon.
Oddly, the movie will apparently feature some dramatization scenes mixed in with real-life footage, with actors playing Chris and other people involved in his life. Lauchlin MacDonald will play Chris Cornell, Robert De Niro's daughter Drena De Niro will play Vicky Cornell, Adelicia Morris will play Chris's mother Karen Cornell and Sandeep will play Soundgarden guitarist Kim Thayil.
IMDB.com - Mark Carol Company

Pearl Jam, Nirvana, Soundgarden and Audioslave will all appear in archival footage. Some are calling the whole project an obvious cash grab by Cornell's widow as archival footage is cheaper than paying the bands, plus the whole semi-documentary "actors" thing (ever see the network Reelz butcher perfectly good stories with interspersed "dramatizations?") The film is due out in 2021.

Although he had a cameo in 1992's Singles, Cornell said in a 2017 interview that he was never interested in becoming an actor: "I think Singles sort of cured me of that aspiration in a way. I mean, it's an art form. I'm a huge fan of cinema and I dedicated myself to music and it's something that I started doing -- I guess from 16 on, that was my chief focus. I knew that was what I was gonna do for the rest of my life, and I feel like acting is the same way. Great actors, that's what their focus is, and I wouldn't pollute the world of cinema with my horrible acting."

Source.