https://bugs.freedesktop.org/show_bug.cgi?id=91333 --- Comment #8 from Mark Cave-Ayland --- Apologies for jumping in on another bug report, however this sounds exactly like the problem I've been struggling with for years on my Lenovo T420s: https://bugs.freedesktop.org/show_bug.cgi?id=56615 I see the same symptoms in that the kernel "hangs" with an external DisplayPort connected in discrete mode when trying to use the internal LVDS with the external monitor. It seems the message I get in the kernel log is similar too: nouveau E[ PDISP][0000:01:00.0] chid 1 mthd 0x0080 data 0x00000000 0x00005080 0x0000000 -- You are receiving this mail because: You are the assignee for the bug.