How do I delete an update to redownload?

Ask Fedora
,
1

I noticed some crc issues with my processor, essentially my overclock was not as stable as I though. I think this broke a recent update to kernel 6.9.4.

I would like to know how do I delete/remove/rollback this update so that I can boot into the previous kernel download/update again?

2

Fedora default saves 2 older kernels and a rescue kernel. If you are using grub, the boot menu will allow you to choose an older kernel. For BIOS boot hold shift down when BIOS screen appears. For UEFI, press the escape key when the boot image (often a vendor’s logo) appears.

1 Like
3

At reboot time you can force the grub menu to show the installed kernels by pressing the Esc key when the bios greeting image shows (usually the bios image or greeting page that shows when the computer first starts up). Select a kernel before 6.9.4 and allow the boot to continue. There’s more than one because Fedora defaults to maintain 3 kernels. You can modify the /etc/dnf/dnf.conf “installonly_limit” to something other than 3 if you want.

When booted up, the easiest way would be dnf reinstall:

sudo dnf reinstall kernel\*6.9.4-200\*

Be careful by inspecting the list of packages, it should be something like this:

Reinstalling:
 kernel                                                 x86_64                                6.9.4-200.fc40                                  updates                                169 k
 kernel-core                                            x86_64                                6.9.4-200.fc40                                  updates                                 17 M
 kernel-devel                                           x86_64                                6.9.4-200.fc40                                  updates                                 20 M
 kernel-headers                                         x86_64                                6.9.4-200.fc40                                  updates                                1.6 M
 kernel-modules                                         x86_64                                6.9.4-200.fc40                                  updates                                 63 M
 kernel-modules-core                                    x86_64                                6.9.4-200.fc40                                  updates                                 37 M
 kernel-modules-extra                                   x86_64                                6.9.4-200.fc40                                  updates                                2.9 M
 kernel-modules-internal                                x86_64                                6.9.4-200.fc40                                  updates                                1.3 M

Accept that with “Y” on the “is this okay” prompt, when that finishes, reboot and you should be booted to 6.9.4.

Another option, if you’re not against using a testing kernel, 6.9.5-200 is out, you could just skip the rebooting to the previous kernel and just jump to 6.9.5-200:

dnf upgrade --enablerepo=updates-testing kernel\*

4

Thank you that worked well.

And if I want to completely remove that kernel and said update, so I can start from scratch how would I go about doing that?

Reason I ask is I didn’t enroll dkms keys with mokutil and my nvidia driver didn’t upgrade properly.

I get this when I reinstall the kernel…

dkms: removing: nvidia 550.78 (6.9.4-200.fc40.x86_64) (x86_64)
Module nvidia-550.78 for kernel 6.9.4-200.fc40.x86_64 (x86_64).
Before uninstall, this module version was ACTIVE on this kernel.

nvidia.ko.xz:

  • Uninstallation
    • Deleting from: /lib/modules/6.9.4-200.fc40.x86_64/extra/
  • Original module
    • No original module was found for this module on this kernel.
    • Use the dkms install command to reinstall any previous module version.

nvidia-uvm.ko.xz:

  • Uninstallation
    • Deleting from: /lib/modules/6.9.4-200.fc40.x86_64/extra/
  • Original module
    • No original module was found for this module on this kernel.
    • Use the dkms install command to reinstall any previous module version.

nvidia-modeset.ko.xz:

  • Uninstallation
    • Deleting from: /lib/modules/6.9.4-200.fc40.x86_64/extra/
  • Original module
    • No original module was found for this module on this kernel.
    • Use the dkms install command to reinstall any previous module version.

nvidia-drm.ko.xz:

  • Uninstallation
    • Deleting from: /lib/modules/6.9.4-200.fc40.x86_64/extra/
  • Original module
    • No original module was found for this module on this kernel.
    • Use the dkms install command to reinstall any previous module version.

nvidia-peermem.ko.xz:

  • Uninstallation
    • Deleting from: /lib/modules/6.9.4-200.fc40.x86_64/extra/
  • Original module
    • No original module was found for this module on this kernel.
    • Use the dkms install command to reinstall any previous module version.
      depmod…

What does the above mean?
The driver is loaded after I added dkms to mokutil, just not sure about that output when I reinstalled the kernel.

5

uninstalling a kernel is similar to installing one.
sudo dnf remove kernel\*6.9.4\*

If you installed the nvidia drivers from rpmfusion and had the modules signed and the key imported into bios then the upgrade of the kernel modules and having them function would work properly.

The nvidia packages from rpmfusion use akmods and not dkms, with instructions for installation and secure boot at Howto - RPM Fusion

1 Like
6

I guess this is the part that confuses me about signing the NVIDIA drivers when installing via RPM fusion…

You will have to enter the BIOS/EFI to import your self generated key.

This will break my secure boot on Windows if I do this , as I will be using custom keys no?

7

If you follow the instructions already provided it will not interfere with windows secure boot.

Windows uses a different key and bios is capable of managing several different keys.

1 Like