Update Kernel & Remove older Kernel = Panic at boot LUKS password prompt

Running KDE Plasma variant here since January 2023.
Updates have been okay.
Today ran updates, then got popup that I had an older non-supported kernel.
I went into Kernels, installed recent 6.4 and removed older kernel.
Now when I boot, instead of getting my ususal LUKS password prompt for my boot partition, I am getting a flashing CAPS Lock key / kernel panic…

Am looking for guidance to boot and fix LUKS problem.
Then looking for a way to get the older kernel installed that LUKS can work with…

Currently I see only this when I power on:
/dev/nvme0n1p2: recovering journal
/dev/nvme0n1p2: clean, 572908/4161536 files, 11676676/16626432 blocks
THEN THE CAPS LOCK FLASHES

I am not sure that the new kernel is your problem, but if it is, than just use live-usb, boot from there, chroot and install another kernel with mhwd-kernel.
The current lts kernel is linux61.
(mhwd-kernel -i linux61)

Just a point of information …
I know the dialogue from msm-notifier is less than desirable … but you dont have any reason to be on the 6.4 kernel.
If you had an actual EOL kernel, such as 6.2 you might need to remove that … but it doesnt mean you need to use the absolute latest kernel.
You can see kernels and their projected lifetimes here: The Linux Kernel Archives - Releases
Also … its generally a bad idea to attempt removal of a running kernel.
You should:

  • A - Install whatever other kernel you like
  • B - Boot into another kernel
  • C - Remove undesired kernel

I was able to do this.

I found that I had to
sudo mhwd-kernel --remove linux64

then
sudo update-grub

then it rebooted to a linux 6.3 kernel that LUKS was okay with.

Thanks all for your guidance :slight_smile:

Manjaro tricked me again.

Pop up came up that I was running an unsupported kernel.

I went into kernel and selected the 6.4 RealTime kernel.

Rebooted.

And sure enough - Kernel Panic
As the newer kernel is not compatible with LUKS.

This is terrible - does this mean the LUKS is not going to be supported in the future?

I can’t even remember how I fixed this from before…

I am down and am scrambling to find a solution.

Do not install realtime kernels without really needing one (if you don’t know the difference - you don’t need it).
Besides, kernel 6.4 is soon going to be EOL, so you can install the brand new 6.5 that just came out. Or just stay on LTS 6.1. Actually you should always have at least 2 kernels, one of which LTS if something goes wrong, for example with an update.

2 Likes