After updating Kubuntu 20.04 packages to latest, login results in system halt

[jasoncollege24]

board is ROG Strix Z390-F Gaming, with latest BIOS update
Intel i9 9900K
RAM: 32GB Dual Channel G-Skill Trident Z RGB (F4-3200C16-16GTZR x2)
Graphics: NVidia GeForce RTX 2080 Super (8GB)
The system booted fine, after maybe a month of not booting to Linux. (Dual boots with Windows 10) after running the following commands:

sudo apt update
sudo apt upgrade -y
sudo apt autoremove -y
shutdown -r now

the OS upgraded all upgradable packages, then rebooted, loaded GRUB, then just went to a black screen.
From here, I rebooted, choosing advanced options for Ubuntu, chose recovery mode, and repaired all packages.
Another reboot got me to the Kubuntu login screen.
I logged in from there, and the system halted. No TTY access, and the numlock on my keyboard even stops functioning.
Only option is to pull the power cord, and boot fresh to do anything else.
Note that Windows 10 boots perfectly fine, and I never had this problem before today. Any help would be greatly appreciated.

[GreyGeek]

Log in using the recovery mode and check the ~/.Xauthority file in your home account. It may be owned by root. It should be owned by you. If it is owned by root then use chown to make it owned by your account name and reboot. If it's not, that's another problem.

[chimak111]

In addition to GreyGeek's advice, Kubuntu users should use sudo apt full-upgrade rather than just sudo apt upgrade.

[jasoncollege24]

turns out this problem seems to have been caused by both nvidia-driver-440, and nvidia-driver-450, both of which caused this. (440 kept installing 450 alongside, thus causing the same problem). removing all nvidia files, and installing nvidia-driver-435 allowed me to boot normally. no idea why this happens, or why either 440, or 450 causes the system to halt.

isn't the used command dependent on what the user wants? sudo apt update tells if anything is out of date, and I've never had an issue, unless packages were held back.

[jglen490]

From man apt:

upgrade (apt-get(8))
          upgrade is used to install available upgrades of all packages currently installed on the system from the sources
          configured via sources.list(5). New packages will be installed if required to satisfy dependencies, but existing
          packages will never be removed. If an upgrade for a package requires the removal of an installed package the
          upgrade for this package isn't performed.

      full-upgrade (apt-get(8))
          full-upgrade performs the function of upgrade but will remove currently installed packages if this is needed to
          upgrade the system as a whole.

The full-upgrade argument may have handled your nvidia-440/450 problem.

As an aside, did you install nvidia-435 from the repos or from Nvidia? Just curious.

[jasoncollege24]

Driver installations are done from the repos. I learned my lesson with that by trying to install later drivers from Nvidia on 19.04. I never got the system right again, and ultimately had to reinstall kubuntu. Wouldn't apt update still tell me there were packages out of date, if full-upgrade was needed? apt seems pretty smart, but I could be wrong. sudo apt-get update also told me the system was up-to-date, as well as Discover, once I got back into the desktop environment.

When I was in recovery mode, I used the option to repair all broken packages, using dpkg. (One of the menu options) Also, when I installed 440/450 respectively, I made sure no other "nvidia" packages were on the system first. I started with 440, and was surprised to see literally only 1 440 package get installed. All others were 450. I did hte same thing, and installed only 450, and it installed the same as 440, without installing the 440 package. Command was:

sudo apt install nvidia-driver-440

To me, that never should've included 450.

This was actually a fairly new install with an old home directory, because I swapped out the OS disk with a new one. Just hadn't had time to mess with it right away

FWIW, I'm only partially new to Linux. I've toyed around with ubuntu on and off since before it had a desktop environment, but never really learned much, until Kubuntu. Devs of both Ubuntu, and Kubuntu have done excellent jobs. For this situation, I have some experience with apt, apt-get, and Discovery for package, and driver installation. this also was a fairly new install with an old home directory, since i swapped out the OS drive. I didn't upgrade drivers on install, so I'm guessing it came with 440, or 450 at install time?

[jglen490]

Maybe it doesn't make sense, but full-upgrade is different from upgrade.

I only do full-upgrade, just based on the definition found in man.

[jglen490]

With respect to what came with the install, it probably would be whatever was considered "appropriate" or recommended. If you run

ubuntu-drivers devices

is will show what is recommended based on the distro version and your video card.

I have a low-end video card and am running 20.04.1, and this is what shows for my system

john@john-Desktop:/etc/cups/ppd$ ubuntu-drivers devices
== /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0 ==
modalias : pci:v000010DEd00000F02sv00000000sd00000000bc03sc00i00
vendor   : NVIDIA Corporation
model    : GF108 [GeForce GT 730]
driver   : nvidia-340 - distro non-free
driver   : nvidia-driver-390 - distro non-free recommended
driver   : xserver-xorg-video-nouveau - distro free builtin

== /sys/devices/pci0000:00/0000:00:14.0/usb1/1-7/1-7:1.0 ==
modalias : usb:v0BDApB812d0210dc00dsc00dp00icFFiscFFipFFin00
vendor   : Realtek Semiconductor Corp.
driver   : rtl88x2bu-dkms - third-party free

[jasoncollege24]

Could've sworn I replied to this...

Figured out why you suggest full-upgrade. It handles issues like held back packages, and would've resolved a number of package related issues in the past. thanks for that!

[Teunis]

A few days ago I had a similar problem when I upgraded using Muon.
When I wanted to reboot to get the new kernel running it ended in a black screen.
Rebooting with other Grub options did not solve the issue.

By switching to a different virtual monitor (Ctrl+Alt+F4) I noticed the OS was still running so next I tried to do a new upgrade.

[FONT=monospace][COLOR=#000000]sudo apt update [/COLOR][/FONT]

[FONT=monospace][COLOR=#000000]sudo apt upgrade[/COLOR][/FONT]

[FONT=monospace][COLOR=#000000]sudo apt update --fix-missing[/COLOR][/FONT]

[FONT=monospace][COLOR=#000000]sudo apt install -f[/COLOR][/FONT]

The last two were a bit of a wide shot.
But a next reboot brought back the desktop.

[claydoh]

[FONT=monospace][COLOR=#000000]sudo apt [B]full-[/B]upgrade[/COLOR][/FONT]

[.

There, I fixed that for ya

[Teunis]

There, I fixed that for ya

Yes that is what Muon also does.
But in this instance I did not do it and yet the desktop came back up.
After all, the main reason was to fix a failed upgrade.