Thanks Tolga. It looks like the root cause of the issue on your machine is a lack of display bandwidth when trying to drive 2 screens through the same cable:
May 11 21:08:51 messier32 kernel: i915 0000:00:02.0: [drm:intel_dp_mst_compute_config [i915]] Trying to find VCPI slots in DSC mode May 11 21:08:51 messier32 kernel: i915 0000:00:02.0: [drm:intel_dp_mst_compute_config [i915]] DSC Source supported min bpp 18 max bpp 24 May 11 21:08:51 messier32 kernel: i915 0000:00:02.0: [drm:intel_dp_mst_compute_config [i915]] DSC Sink supported min bpp 0 max bpp 0 May 11 21:08:51 messier32 kernel: i915 0000:00:02.0: [drm:intel_dp_mst_find_vcpi_slots_for_bpp.constprop.0.isra.0 [i915]] failed finding vcpi slots:-22 May 11 21:08:51 messier32 kernel: i915 0000:00:02.0: [drm:intel_atomic_check [i915]] [ENCODER:106:DP-MST C] config failure: -22 I'm not sure if that's an "expected" or "normal" error which we should expect to see on some setups forever, or if it's a kernel bug. If it's "expected" then ideally mutter/gnome-shell should fail more gracefully but I don't know how that's possible given how limited the atomic API is. You can never find out _what_ failed, only that something failed. I hate atomic KMS. Did the workaround work for you? MUTTER_DEBUG_ENABLE_ATOMIC_KMS=0 MUTTER_DEBUG_FORCE_KMS_MODE=simple in /etc/environment -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to mutter in Ubuntu. https://bugs.launchpad.net/bugs/1968040 Title: [i915] Blanked screen doesn't wake up after locking [drmModeAtomicCommit: Argument invalide] [drmModeAtomicCommit: Invalid argument] To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-shell/+bug/1968040/+subscriptions -- desktop-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
