Hi, I can confirm that James' patch fixes the issue for me as well, on 4.9.0-rc5. Without the patch, X can't start for me neither on 4.8 nor on 4.9.0-rc5, but works fine on 4.7. I'm using a pitcairn graphic card.
Would be nice to get the files included soon, as it is effectively making testing/stretch systems with radeon SI/CI cards unbootable right now. Cheers + thanks, Mika --
pgpDkFTgOmcXP.pgp
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