Fedora 43 upgrade failed: had to manually reboot, now GDM coredumps

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21

Hi
this help me a lot.
Fedora workstation installed in 2024 on my computer, I upgrade to 43 today.
It was Fedora 42 I think, but I can see an old Fedora39 in the listed os in grub or /boot
I use Wayland.
Maybe Wine or Lutris have changed some parameters, before upgrading, I can see some incompatibilities with some wine files, so, I uninstall Wine and Lutris.

But after upgrading to 43, I have the same gdm error.
/etc/gdm/custom.conf have the line WaylandEnable=false, so I rename the file (I think just adding " before the line is ok)

22

I had the same issue. After I followed what is described in this discussion, it worked again for me:

23

That worked for me. I had repeated the upgrade on my backup disk and the result was exactly the same so repeatable fault. Thanks.

24

Ok … so, the “right answer” is likely:

  1. sudo authselect select local --force (two dashes for the switch)

    and the specific line corrected should look like this in nsswitch.conf

    shadow: files systemd

  2. Gnome decided to eliminate X by default so, this will break GDM IF /etc/gdm/custom.config has WaylandEnable=false. You will need to comment that line or remove it.

  3. reboot

3 Likes
25

I have the same issue as described by others here, however the recommended fixes did not resolve it for me.

journalctl -b shows that the gnome-shell dumped the core.

In addition to what others described sudo dnf distro-sync --refresh also fails:
First, when updating and loading repositories, it only checks Fedora 42 repositories, then it fails and finds problems:

  • [...] .i686 from @System has inferior architecture
  • [...] but none of the providers can be installed

I uses the graphical interface to start the update if that makes any difference.

cat fedora-release shows 43 so it doesn’t match the reposotories.

Does anyone have a hint what I can do?

26

Have you tried sudo dnf distro-sync --refresh --releasever=43 to ensure dnf is only looking at the f43 repo.?

It is also possible that the upgrade is failing because of the i686 packages, and we really would need to see the full detail of the reported conflict/errors before we could make appropriate suggestions.

Graphical interface? as in from a terminal window on the desktop? or the gnome software app?
There is a distinct difference. Dnf on the desktop uses dnf5 while the software app uses the older dnf4. Dnf in the terminal displays what will be updated and reports any errors while the software app hides that information.

For me, I always suggest following the instructions here for performing release version upgrades (as I already suggested above).

27

I would try to remove all packages that have .i686 architecture (keep a
list, so you can re-install them later), then run that distro-sync
–refresh call posted earlier. No guarantees, though :slight_smile:

28

Thanks for your replies! I was traveling last week and now made sure that my backups are up to date and I have access to a second computer so I feel safer to test things out.

@computersavvy Yes, when I said ‘graphical interface’ I meant the Gnome Software App, thinking this would be the easiest and safest way to do it. I did not know that the two methods are actually doing different things under the hood. In the future I’ll stick to your suggestions.

I have removed the remaining .i686 package as @jovetoo suggested and running sudo dnf distro-sync --refresh --releasever=43 returns"

Updating and loading repositories: 
RPM Fusion for Fedora 43 - Nonfree
RPM Fusion for Fedora 43 - Nonfree - Updates
RPM Fusion for Fedora 43 - Free - Updates
RPM Fusion for Fedora 43 - Free
ProtonVPN Fedora Stable repository
Fedora 43 - x86_64
Fedora 43 openh264 (From Cisco) - x86_64
RPM Fusion for Fedora 43 - Free tainted
Fedora 43 - x86_64 - Updates
Copr repo for hyprland owned by solopasha
Docker CE Stable - x86_64
Repositories loaded.
Failed to resolve the transaction:
Problem: The operation would result in removing the following protected packages: NetworkManager, gnome-shell, grub2-tools-minimal, selinux-policy-targeted, setup, sudo, systemd, systemd-udev
You can try to add to command line: 
--skip-broken to skip uninstallable packages

Safe to say I did not want to go ahead with this and adding --skip-broken generates the same output just without the suggestion.

Do you have other suggestions how I can diagnose what went wrong and maybe fix it?
And, if that doesn’t work, are there ways to reinstall Fedora while leaving my home directory in tact?

I have found these instructions that sound like they should be able to fix my problem, but I don’t fully understand them and they seem to be designed as test case for Fedora 44 and not to fix my problems.

29

Bumping this, because I’m getting a bit desperate

30

You can easily reinstall Fedora while keeping the home directory intact. Just start the installer and choose to manually lay out the drive partitions and mount your home paritition on /home without formatting it. Format all other drives to be sure.

31

I’ll try this. The Fedora installer even offers “Reinstall Fedora” as a one-click option, but this throws the error message that automatic partitioning fails due to lack of space for /boot.

The instructions I linked earlier only recommend using the GTK-based installer, I assume what I have is the WebUI installer as instructions don’t match what I see.

My selections are shown in the image here, but for me it is counter intuitive that / will be a subvolume and not /home .

Given that I didn’t understand the instructions very maybe someone could tell me if this will work aa intended.

Installer_Selection
Installer_Selection1920×1446 179 KB

Installer_Overview
Installer_Overview1920×982 187 KB

32

Hi Philipp,

I would be inclined to disable the3rd party repos before doing anything else and see what happens. Looks like ProtonVPN Fedora Stable repository, Copr repo for hyprland owned by solopasha and Docker CE Stable - x86_64 are 3rd party ……

Also,

I usually use the command line method for my upgrades as it seems to be more consistent ….

as root or via sudo:

  1. dnf upgrade --refresh

  2. dnf upgrade -y

  3. reboot

  4. dnf install dnf-plugin-system-upgrade

  5. dnf system-upgrade download --releasever=43 -y

  6. dnf5 offline reboot

  7. dnf system-upgrade clean

  8. dnf clean all

… Watch for errors … if none and everything upgades for the OS, then try upgrading the 3rd party stuff …..

33

Thanks @einer for your suggestions. At first I thought that the third party repositories would not make much of a different, or at least not cause core dumps with gdm.

I disabled the third party repositories and after a reboot gdm does not crash anymore and I have a working (mostly) system.

dnf upgrade --refresh still checks Fedora 42 repositories

➜  ~ sudo dnf upgrade --refresh
Updating and loading repositories:
 RPM Fusion for Fedora 42 - Nonfree                                                                                                                   100% |   5.3 KiB/s |   8.8 KiB |  00m02s
 RPM Fusion for Fedora 42 - Nonfree - Updates                                                                                                         100% |   5.4 KiB/s |   8.2 KiB |  00m02s
 RPM Fusion for Fedora 42 - Free - Updates                                                                                                            100% |   6.3 KiB/s |   8.2 KiB |  00m01s
 RPM Fusion for Fedora 42 - Free                                                                                                                      100% |   8.4 KiB/s |   8.9 KiB |  00m01s
 Fedora 42 openh264 (From Cisco) - x86_64                                                                                                             100% |   1.1 KiB/s | 986.0   B |  00m01s
 Fedora 42 - x86_64                                                                                                                                   100% |  39.3 KiB/s |  24.6 KiB |  00m01s
 Fedora 42 - x86_64 - Updates                                                                                                                         100% |  12.7 KiB/s |   5.2 KiB |  00m00s
 RPM Fusion for Fedora 42 - Free tainted                                                                                                              100% |  38.5 KiB/s |   8.2 KiB |  00m00s
Repositories loaded.
Problem: installed package libvirt-daemon-driver-storage-core-11.6.0-2.fc43.x86_64 obsoletes libvirt-daemon-driver-storage-zfs < 11.4.0 provided by libvirt-daemon-driver-storage-zfs-11.0.0-5.fc42.x86_64 from updates
  - cannot install the best update candidate for package libvirt-daemon-driver-storage-zfs-11.0.0-4.fc42.x86_64
  - cannot install the best update candidate for package libvirt-daemon-driver-storage-core-11.0.0-4.fc42.x86_64

Nothing to do.

So I have to add --releasever=43 everytime I use dnf. This at least works for dnf upgrade, but dnf system-upgrade download --releasever=43 still fails and tells me it would have to uninstall systemd, sudo and other things.

Updating and loading repositories:
Repositories loaded.
Failed to resolve the transaction:
Package "rpmfusion-nonfree-release-42-1.noarch" is already installed.
Package "rpmfusion-nonfree-release-43-1.noarch" is already installed.
Package "rpmfusion-free-release-42-1.noarch" is already installed.
Package "rpmfusion-free-release-43-1.noarch" is already installed.
Package "localsearch-3.9.0-1.fc42.x86_64" is already installed.
Package "localsearch-3.10.1-1.fc43.x86_64" is already installed.
Package "tinysparql-3.10.1-1.fc43.x86_64" is already installed.
Package "totem-video-thumbnailer-1:43.2-6.fc43.x86_64" is already installed.
Package "vte-profile-0.80.4-1.fc42.x86_64" is already installed.
Package "vte-profile-0.82.1-1.fc43.x86_64" is already installed.
Package "qcom-wwan-firmware-20251021-1.fc42.noarch" is already installed.
Package "qcom-wwan-firmware-20251021-1.fc43.noarch" is already installed.
Package "fedora-flathub-remote-1-10.fc42.noarch" is already installed.
Package "fedora-flathub-remote-1-11.fc43.noarch" is already installed.
Package "fedora-workstation-repositories-38-8.fc43.x86_64" is already installed.
Package "thermald-2.5.9-2.fc43.x86_64" is already installed.
Package "aurorae-6.5.2-1.fc43.x86_64" is already installed.
Packages for argument 'sddm-breeze' available, but not installed.
Packages for argument 'qt5-qtwebengine-freeworld' available, but not installed.
Problem: The operation would result in removing the following protected packages: NetworkManager, gnome-shell, grub2-tools-minimal, selinux-policy-targeted, setup, sudo, systemd, systemd-udev

So my system is still in a weird state, that I don’t really understand and I will likely reinstall in the next few days, but at least for now it kinda works.
Thanks for your help.

34

Try this and it may solve the problem.
sudo dnf distro-sync --releasever=43

You also appear to have duplicates of some packages, so that can be cleared up with a couple other dnf commands such as sudo dnf rq --duplicates to identify the duplicate packages then they could be removed.

Having an upgrade between release versions fail often causes problems.

You may have to do sudo dnf reinstall fedora-release-common --releasever=43 or sudo dnf upgrade fedora-release-common --releasever=43 to get the files in /etc updated to show the proper, already in place, release version which should eliminate the need for using the --releasever option with every dnf command.
Those files are /etc/fedora-release /etc/os-release /etc/redhat-release /etc/system-release and dnf looks at one to see the currently installed release version.

You can see what those files contain with the cat command. cat /etc/*-release will show the content of all 4 files.

35

Fedora 43 upgrade → GDM core dumps / black screen (NVIDIA) – Working fix

Summary

After upgrading from Fedora 42 → Fedora 43, systems with NVIDIA GPUs may fail to reach the graphical login. The system boots, but the GUI never appears.

This is not an NVIDIA driver issue. The kernel and NVIDIA driver load correctly.
The failure happens during the GDM → GNOME handoff after the upgrade.

Symptoms

  • Boot stops at a black screen or shows scrolling [ OK ] boot messages
  • Ctrl + Alt + F2 / F3 opens a TTY, but no GUI appears
  • gdm.service fails or core-dumps
  • nvidia-smi works correctly
  • Wayland disabled, but the issue persists

Example:

systemctl status gdm
# gdm.service: failed (core-dump)

journalctl -u gdm
# GDM crashes inside glib / gio / systemd libs

Even after:

  • reinstalling gdm / gnome-shell
  • disabling Wayland
  • fixing the gdm-greeter shadow entry

GDM may still fail and only produce a black screen.

Root cause (observed)

After the Fedora 43 upgrade, GDM remains broken on some systems, especially with NVIDIA GPUs.
Although the NVIDIA driver works (nvidia-smi OK), GDM crashes before showing the login screen.

This appears to be a GDM / GNOME regression, not a driver or kernel problem.

Working solution (confirmed)

Switch to LightDM as a workaround (temporary or permanent).

LightDM uses a simpler login path and successfully starts GNOME when GDM fails.

Steps

From a TTY (Ctrl + Alt + F2):

sudo dnf install lightdm lightdm-gtk -y

Disable GDM and enable LightDM:

sudo systemctl disable gdm
sudo systemctl enable lightdm

Ensure graphical boot:

sudo systemctl set-default graphical.target

Reboot:

reboot

Result

  • LightDM login screen appears
  • GNOME desktop loads normally
  • NVIDIA works correctly (nvidia-smi OK)
  • System becomes usable again

LightDM works reliably even when GDM continues to fail after the Fedora 43 upgrade.

Optional: switch back to GDM later

Once Fedora fixes the GDM regression, you can try switching back:

sudo systemctl disable lightdm
sudo systemctl enable gdm
reboot

If GDM still fails, LightDM can safely be kept as the default display manager.

Notes

  • Observed after Fedora 42 → 43 upgrades
  • Affects systems with NVIDIA GPUs
  • Not fixed by reinstalling drivers alone
  • Not fixed by disabling Wayland alone
  • LightDM is a supported and stable workaround

Tested on

  • Fedora 43 Workstation
  • NVIDIA GTX 1650 (akmod-nvidia)
  • Wayland disabled

Posting this so others hitting a black screen / GDM core dump after upgrading to Fedora 43 can recover without reinstalling the OS.

36

Are you sure that GNOME is really running under X11? In Fedora 43 GNOME ships with no support for an X11 session.

37

That is what i did initially to get a gui running but did you try the simple fix using authselect? Manually "edit /etc/nsswitch.conf (sudo vi /etc/nsswitch.conf)

and on the line that looks like this

shadow: files

change that line to look like the following

shadow: files systemd

save and reboot"

38

On my system, it was already configured as files systemd; however, the GUI still failed to start. Switching to LightDM resolved the issue.

39

X11 still supported on GNOME I guess.