Boot failing with LTS kernel

pled · October 27, 2025, 11:14am

HI,

Got exactly same issue with my very new endeavousOS install (I am new to this OS, just discovering it since a couple of days).
This morning, I updated the system, then at reboot, got that error (failed to mount /sysroot).

I confirm nothing can be done at boot time : entering password or Ctrl-D has no effect, system is totally dead.
dracut version is 108, and I have LTS kernel installed and used by default.
kernel mainline is 6.17.5.arch1-1 & kernel LTS is 6.12.55-1 (cannot boot)

=> I had to enter Grub menu and choose kernel 6.17.5 to boot successfully.

Let me know if you need more information, or tell me how to fix that.
Should I remove LTS kernel ?? (which is illogical isn’t it ?).
Thanks.

xircon · October 27, 2025, 11:24am

Just for clarity - which exact version of dracut do you have? (Hint it should be 108_eos-1).

pled · October 27, 2025, 12:00pm

Yes, this is dracut 108_eos-1.

$ sudo pacman -Q dracut
dracut 108_eos-1

dalto · October 27, 2025, 12:10pm

I moved this to a new topic since there are a lot of reasons that error can occur and it probably isn’t related to that other posters issue.

First, try booting into the kernel that works and running sudo dracut-rebuild.

If that doesn’t fix it, you need to find the actual error. Failed to mount sysroot is a secondary error. The actual error, the reason it fails to mount sysroot, is further up in the boot text.

pled · October 27, 2025, 2:53pm

I did run dracut-rebluid, but no change to the issue. But there are some good news although I don’t understand everything, this beyond my knowledge :

I forgot to mention I am using rEFInd to boot. My desktop is configured to dual-boot between Debian and EndeavourOS. On Debian, I have installed rEFInd a long time ago (thus only installed from Debian). Then I installed EndeavourOS some days ago, and I was able to boot EOS using rEFInd boot manager, so far so good (booting directly from the EOS boot loader, and not using GRUB).

Until this morning : as I said, I updated the EOS (pacman -Syu), and after a reboot, I got the system stuck with the “failed to mount /sysroot“ error.

After some more testing, here is what I observe :

If I select the /boot/efi/EFI/endeavouros/grubx64.efi option, I can boot EOS selecting LTS kernel. Note this is from the system EFI partition.
If I select the /boot/vmlinuz-linux-lts option, then I get the system stuck with “Failed to mount /sysroot“ error. Note this is from the system disk where EOS is installed.
I can boot from both Debian similar choices (Grub or Debian boot loader).

If I am correct, the 2nd option is to boot directly from the boot loader on the ext4 system partition (when the first one is the grub boot manager from FAT32 EFI partition).

Here is the content of the boot dir :

$ sudo ls -al /boot
total 217340
drwxr-xr-x  4 root root     4096 27 oct.  14:41 .
drwxr-xr-x 22 root root     4096 25 oct.  17:41 ..
-rw-r–r--  1 root root   184320 22 oct.  01:12 amd-ucode.img
drwxr-x—  3 root root     4096  1 janv.  1970 efi
drwxr-xr-x  6 root root     4096 14 oct.  16:32 grub
-rw-------  1 root root 62639144 27 oct.  14:41 initramfs-linux-fallback.img
-rw-------  1 root root 32729064 27 oct.  14:41 initramfs-linux.img
-rw-------  1 root root 62453688 27 oct.  14:40 initramfs-linux-lts-fallback.img
-rw-------  1 root root 34070862 27 oct.  14:40 initramfs-linux-lts.img
-rw-r–r--  1 root root 16523455 25 oct.  17:41 vmlinuz-linux
-rw-r–r--  1 root root 13918720 27 oct.  10:22 vmlinuz-linux-lts

Does that mean the vmlinuz-linux-lts file is wrong or corrupted somewhere ? timestamp is probably time of the system update this morning.

Here is where I am…

dalto · October 27, 2025, 2:56pm

It is probably an issue with your refind config. Did you update the refind config to tell it to look for the LTS kernel?

You need to update extra_kernel_version_strings in refind.conf. This line will handle all standard Arch kernels:

extra_kernel_version_strings "linux-hardened,linux-rt-lts,linux-zen,linux-lts,linux-rt,linux"

wolfn · October 27, 2025, 4:08pm

Man, you saved my day!
On my notebook I did so - and it worked, on my PC I forgot it (to uncomment…) and got the problem. Never thought about this.

Hope, it will help @pled also…

Thank you, very much!

pled · October 27, 2025, 4:29pm

Perfect guess ! that was the problem, all is right now.

Thank you so much, you’ve hit the nail on the head !

system · October 29, 2025, 4:29pm

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