My laptop is running Pop!_OS 22.04 and has just updated the kernel to 6.0.2 which has broken the driver for my DisplayLink USB 3.0 Dock which runs fine under the previous kernel. I know I can switch the Kernel at boot by spamming the space bar and selecting the pop_os-oldkern.conf but sometimes I forget to do this, so I was wondering if there was a way switch back to the old kernel permanently?
I haven’t used grub in a while, but I know you can edit /boot/grub/grub.cfg to change the default boot option. Or you can just rename the vmlinuz and initramfs from /boot and make symbolic links pointing to the older 5 versions, with the name of the version 6 kernel and initramfs.
Pop!_OS uses systems-boot from what I’ve read not Grub
Oh, then you can still get away with the second option.
sudo -i
cd /boot
mv vmlinuz-6.0.xxx vmlinuz-6.0.xxx.old
ln -s vmlinuz-5.19.xxx vmlinuz-6.0.xxx
mv initramfs-6.0.xxx.img initramfs-6.0.xxx.img.old
ln -s initramfs-5.19.xxx initramfs-6.0.xxx.img
This is assuming your old kernel image and initramfs were not purged by the update process. This should basically leave you with the old image by default. I did hear on the Level1 Forums that people are complaining about Pop!_OS a lot, with virtualization, passthrough, bluetooth and other things, supposedly because of how System76 customizes the kernel (enabling / disabling cache, certain flags and other stuff). I am glad I recommend people use Fedora.
I did some digging last night and found that if I edited the /boot/efi/loader/loader.conf file to say Pop_OS-oldkern instead of Pop_OS-current I was able to use the old kernel.
Now all I need do is wait for DisplayLink to update their driver.