Comment 59 for bug 1716857

Another correction. For the one workaround, switching to discrete graphics in the BIOS only seemed to get past the initial gnome login. But resuming from DPMS off/suspend, the same error loop happens even when hybrid graphics is disabled in the BIOS.

Even worse, seems hardware acceleration ends up being disabled:

$ journalctl --no-hostname -b -p warning _COMM=gnome-shell
-- Logs begin at Wed 2019-02-06 14:13:52 SAST, end at Sun 2020-05-03 16:09:45 SAST. --
May 03 14:51:40 org.gnome.Shell.desktop[2284]: glamor: 'wl_drm' not supported
May 03 14:51:40 org.gnome.Shell.desktop[2284]: Missing Wayland requirements for glamor GBM backend
May 03 14:51:40 org.gnome.Shell.desktop[2284]: Failed to initialize glamor, falling back to sw
...
May 03 14:53:25 gnome-shell[6549]: setup_framebuffers: assertion 'width > 0' failed

The "EGL failed to allocate resources" error stops happening probably because gnome-shell isn't even using hardware acceleration now.

I've also disabled all gnome shell extensions to avoid noise/errors in the logs and will try weed out the problem better.

I checked `grep -C2 -E '(EE)|(WW)' /var/log/Xorg.0.log` and things seem fine:

[ 45.181] (II) NVIDIA dlloader X Driver 440.59 Thu Jan 30 01:08:17 UTC 2020
[ 45.181] (II) NVIDIA Unified Driver for all Supported NVIDIA GPUs
--
[ 45.182] (II) LoadModule: "ramdac"
[ 45.182] (II) Module "ramdac" already built-in
[ 45.183] (WW) Falling back to old probe method for modesetting
[ 45.183] (II) NVIDIA(0): Creating default Display subsection in Screen section
 "Default Screen Section" for depth/fbbpp 24/32
--
[ 46.392] (==) NVIDIA(0): Silken mouse enabled
[ 46.392] (==) NVIDIA(0): DPMS enabled
[ 46.393] (WW) NVIDIA(0): Option "PrimaryGPU" is not used
[ 46.393] (II) Loading sub module "dri2"
[ 46.393] (II) LoadModule: "dri2"

Note, I've done no customisation to X config - trying to stick to defaults.

xrandr confirms only one provider / hybrid is indeed off and Intel not in use:

$ xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x218 cap: 0x1, Source Output crtcs: 4 outputs: 6 associated providers: 0 name:NVIDIA-0

I'm guessing the Lenovo P53 impliments a mux/switch to connect the laptop panel to the NVidia card so that Intel is disabled in this mode.

And double checking, also no i915 modules are loaded:

$ lsmod | grep '^drm'
drm_kms_helper 180224 1 nvidia_drm
drm 491520 10 drm_kms_helper,nvidia_drm

So there seems to be, on current Ubuntu 18.04.4 LTS (fully up to date as of today), a 4K / UHD 60Hz issue with Nvidia, as seen in X log

[ 45.228] (II) NVIDIA GLX Module 440.59 Thu Jan 30 01:05:38 UTC 2020

Lastly, I think due to `needs_root_rights=yes` in /etc/X11/Xwrapper.config, X logs to /var/log/Xorg.0.log again instead of the X without root which used to log at ~/.local/share/xorg/Xorg.0.log