Comment 46 for bug 1878670

Well, similar experience for me today, booted and logged in okay, but then the desktop session died leaving monitor backlight and keyboard lights on, but no other sign of life. Shutting lid to suspend then resume didn't help, had to hard power off. Then on next boot, it hung after login, but recovered and was fine thereafter. More oddness, but not the gpu in the blame this time.

Log sequence extracts:

May 26 09:28:03 xps2020 systemd[1]: Startup finished in 5.461s (firmware) + 3.431s (loader) + 14.216s (kernel) + 20.511s (userspace) = 43.620s.

...

May 26 09:29:14 xps2020 update-notifier.desktop[4555]: /usr/lib/ubuntu-release-upgrader/check-new-release-gtk:30: PyGIWarning: Gtk was imported without specifying a version first. Use gi.require_version('Gtk', '3.0') before import to ensure that the right version gets loaded.
May 26 09:29:14 xps2020 update-notifier.desktop[4555]: from gi.repository import Gtk
May 26 09:29:14 xps2020 update-notifier.desktop[4555]: WARNING:root:timeout reached, exiting
May 26 09:29:14 xps2020 gnome-session[1422]: gnome-session-binary[1422]: WARNING: Application 'org.gnome.SettingsDaemon.Color.desktop' failed to register before timeout
May 26 09:29:14 xps2020 gnome-session-binary[1422]: WARNING: Application 'org.gnome.SettingsDaemon.Color.desktop' failed to register before timeout
May 26 09:29:14 xps2020 gnome-session-binary[1422]: Unrecoverable failure in required component org.gnome.SettingsDaemon.Color.desktop
May 26 09:29:14 xps2020 gnome-session[1422]: gnome-session-binary[1422]: CRITICAL: We failed, but the fail whale is dead. Sorry....
May 26 09:29:14 xps2020 gnome-session-binary[1422]: CRITICAL: We failed, but the fail whale is dead. Sorry....

...

May 26 09:29:15 xps2020 systemd[1]: Stopped User Manager for UID 121.
May 26 09:29:15 xps2020 systemd[1]: Removed slice User Slice of gdm.
May 26 09:29:54 xps2020 PackageKit[1605]: get-updates transaction /309_bcbbbbbe from uid 1001 finished with success after 398ms
May 26 09:29:57 xps2020 org.gnome.Shell.desktop[3032]: ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
May 26 09:29:57 xps2020 org.gnome.Shell.desktop[3032]: ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
May 26 09:30:09 xps2020 systemd-logind[1187]: Lid closed.
May 26 09:30:09 xps2020 systemd-logind[1187]: Suspending...

...

May 26 09:30:13 xps2020 systemd-logind[1187]: Lid opened.
May 26 09:30:23 xps2020 systemd-logind[1187]: Power key pressed.
May 26 09:30:31 xps2020 systemd-logind[1187]: Power key pressed.
May 26 09:30:39 xps2020 systemd-logind[1187]: Delay lock is active (UID 1001/martin, PID 3032/gnome-shell) but inhibitor timeout is reached.
May 26 09:30:39 xps2020 systemd[1]: Starting TLP suspend/resume...
May 26 09:30:39 xps2020 systemd[1]: Started TLP suspend/resume.
May 26 09:30:39 xps2020 systemd[1]: Reached target Sleep.
May 26 09:30:39 xps2020 systemd[1]: Starting Suspend...
May 26 09:30:39 xps2020 systemd-sleep[4909]: Suspending system...
May 26 09:30:39 xps2020 kernel: PM: suspend entry (s2idle)
May 26 09:30:41 xps2020 kernel: PM: Syncing filesystems ... done.
May 26 09:30:41 xps2020 kernel: Freezing user space processes ... (elapsed 0.002 seconds) done.
May 26 09:30:41 xps2020 kernel: OOM killer disabled.
May 26 09:30:41 xps2020 kernel: Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
May 26 09:30:41 xps2020 kernel: printk: Suspending console(s) (use no_console_suspend to debug)
May 26 09:30:41 xps2020 kernel: psmouse serio1: Failed to disable mouse on isa0060/serio1
May 26 09:30:41 xps2020 kernel: PM: Some devices failed to suspend, or early wake event detected
May 26 09:30:41 xps2020 kernel: OOM killer enabled.
May 26 09:30:41 xps2020 kernel: Restarting tasks ... done.
May 26 09:30:41 xps2020 kernel: thermal thermal_zone6: failed to read out thermal zone (-61)
-- Reboot --

...

May 26 09:32:03 xps2020 systemd[1]: Startup finished in 5.443s (firmware) + 3.530s (loader) + 11.642s (kernel) + 33.978s (userspace) = 54.594s.

...

May 26 09:33:37 xps2020 kernel: snd_hda_intel 0000:00:1f.3: No response from codec, resetting bus: last cmd=0x20170500
May 26 09:33:38 xps2020 kernel: snd_hda_intel 0000:00:1f.3: No response from codec, resetting bus: last cmd=0x20370500
May 26 09:33:39 xps2020 kernel: snd_hda_intel 0000:00:1f.3: No response from codec, resetting bus: last cmd=0x20470500
May 26 09:33:40 xps2020 gnome-session[2043]: gnome-session-binary[2043]: WARNING: Application 'org.gnome.Shell.desktop' failed to register before timeout
May 26 09:33:40 xps2020 gnome-session-binary[2043]: WARNING: Application 'org.gnome.Shell.desktop' failed to register before timeout
May 26 09:33:40 xps2020 gnome-session-binary[2043]: Unrecoverable failure in required component org.gnome.Shell.desktop
May 26 09:33:40 xps2020 gnome-session[2043]: gnome-session-binary[2043]: CRITICAL: We failed, but the fail whale is dead. Sorry....
May 26 09:33:40 xps2020 gnome-session-binary[2043]: CRITICAL: We failed, but the fail whale is dead. Sorry....
May 26 09:33:40 xps2020 at-spi-bus-launcher[2141]: XIO: fatal IO error 11 (Resource temporarily unavailable) on X server ":1"
May 26 09:33:40 xps2020 at-spi-bus-launcher[2141]: after 161 requests (161 known processed) with 0 events remaining.

Full logs in attachment. Feels like this has to be more than one issue, though perhaps the worst symptoms all have a common root cause.