Comment 22 for bug 1751268

ok. First, a note that yesterday and today's test were with kernel-4.15.17-300.fc27.x86_64

Couldn't get past a few seconds into the boot (the original failure mode) till I remembered that I'd taken the nouveau modules out of the initfs yesterday. Put it back, booted with drm.debug-14.

It certainly seems that without nouveau taking the hit for whatever goes wrong in the initial kms, things are toast. nouveau times out, hands off to i915, which finishes the kms. However, if there's no nouveau in the kernel, i915 fails the initial mode swich entirely.

Anyway, this boot went clear to runlevel 3 with no errors this time, so I logged on console as root, saved a dmesg (attached). Then exit'd from root's bash.... and things hung. A bit later these errors came to console:

pr 26 14:47:24 entropy kernel: [drm:drm_atomic_helper_wait_for_flip_done [drm_kms_helper]] *ERROR* [CRTC:37:pipe A] flip_done timed out
Apr 26 14:47:24 entropy kernel: [drm:drm_atomic_helper_wait_for_flip_done [drm_kms_helper]] *ERROR* [CRTC:47:pipe B] flip_done timed out

after which I leaned on the power switch to shut down.

Since it didn't go down cleanly, "journalctl -b -1" can't count its instances correctly. But, things did go to /var/log/messages this time, so the complete /var/log/messages for that session is also attached. To sync the two different time series, the dmesg ends around 14:44:44 in messages.