[SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

FdAndL · 2023-09-03 14:19:00

Hi everyone,
I recently installed Arch Linux in a laptop where I already had Windows and Ubuntu.
Because I already had an EFI partition (created during my Ubuntu installation) I did not create a new one as suggested by Arch installation guide. Since, prior to Arch, I had already a dual boot Ubuntu+Windows, I had already grub (installed from Ubuntu) to handle the boot process. Immediately after the Arch installation, Grub was not detecting Arch, but that was just a matter of updating the Grub to detect the new installation and "automatically" create a menu entry for Arch.

The issue I am facing now: Arch is now missing from the Grub menu.

If I ran (this is in Ubuntu):

sudo os-prober

I obtain

/dev/nvme0n1p1@/EFI/Microsoft/Boot/bootmgfw.efi:Windows Boot Manager:Windows:efi
/dev/sda1:FreeDOS:FreeDOS:chain
/dev/sda3:Arch Linux:Arch:linux
device-mapper: remove ioctl on osprober-linux-sda3  failed: Device or resource busy
Command failed.

where, as you can see,

os-prober

seems to have an issue with Arch. Also

sudo grub-mkconfig

fails to create an entry.

I have tried to solve this on my own by reading stuff online but with no success. Here's what I tried:

1) Manually creating a Grub entry for Arch, i.e., I edited the file

/etc/grub.d/40_custom

and added the entry

bc|#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry "Arch" {
	search --set=root --fs-uuid e4c8978b-aa98-49d2-bd1a-63b6d71f0a8e
	linux /boot/vmlinuz-linux root=UUID=e4c8978b-aa98-49d2-bd1a-63b6d71f0a8e
}

where the UUID is the UUID of the partition where I installed

root

during the Arch installation process.

The entry is created but then there is a Kernel panic.

2) Update Grub in Ubuntu

3) Booted arch from Arch's live USB and updated Arch (I thought I had an old kernel or something like that).

4) Re-installed Arch

Do you have any suggestions?

During this process, I understood how little I understand about bootloaders/kernels, etc.. and so I have a question just for understanding:
If, in Ubuntu, I navigate ran

ls -l /boot/efi

(this is where my efi partition is mounted in Ubuntu), I obtain

total 101338
drwxr-xr-x 4 root root      512 set 14  2017  boot-sav
drwxr-xr-x 5 root root      512 ago 20  2017  EFI
-rwxr-xr-x 1 root root 74067037 set  3 15:22  initramfs-linux-fallback.img
-rwxr-xr-x 1 root root 17027305 set  3 15:22  initramfs-linux.img
drwxr-xr-x 4 root root      512 fev  9  2018 'System Volume Information'
-rwxr-xr-x 1 root root 12673312 set  3 15:21  vmlinuz-linux

The

 vmlinuz-linux

that appears last is the kernel for Arch or for what (maybe Grub?)? Maybe my question doesn't make alot of sense but it is just that I don't understand this stuff.
Thanks for your help

Last edited by FdAndL (2023-09-03 18:50:59)

kermit63 · 2023-09-03 15:16:00

I've read reports about a month ago that the older grub version that comes with ubuntu is incompatible with the arch linux kernel. I can't verify this for sure since I don't multi-boot.

If this is still the case, then your options will be to use a newer version of grub in ubuntu (if that is at all possible), or to install grub in arch and let it control the other OSes in your system.

FdAndL · 2023-09-03 15:24:11

Hi Kermit,
Thanks for your reply. But in that case how come this is a recent issue, i.e., grub used to recognize arch. Maybe there was a a grub-update in my Ubuntu that I didn't take notice?
Thanks

kermit63 · 2023-09-03 16:01:43

It has nothing to do with ubuntu updates. Some features were removed from the recent arch kernels that made it incompatible with older grub versions.

seth · 2023-09-03 18:06:05

The entry is created but then there is a Kernel panic.

Please don't paraphrase, https://bbs.archlinux.org/viewtopic.php?id=57855
In doubt, link a photo of the panic (assuming there's any output to support that assumption)

device-mapper: remove ioctl on osprober-linux-sda3 failed: Device or resource busy
Command failed.

Check the dmesg for IO errors after this (in ubuntu)
Also see https://wiki.archlinux.org/title/SMART
(Don't freak out, this is just a precaution - the behavior does not *have* to be malign but could be a bug in os-prober, depending on how old the Ubuntu version is)

FdAndL · 2023-09-03 18:50:40

Hi Seth,
Thanks for your reply. I search the issue mentioned by Kermit and I found that there were reports of conflicts between ubuntu Grub and Arch. See for example https://forum.endeavouros.com/t/you-can … rub/6328/3 where they mention this.

So in the end what I did was just arch-chroot with a live USB and install grub for arch. I now have arch grub managing both Ubuntu and Arch and everything is going well.

It was not exactly the solution I was looking for, since I was trying to actually fix the issue without installing another grub. But fixing it was clearly beyond my abilities.

Thank you to you both and I am going to mark this as SOLVED.

seth · 2023-09-03 19:01:06

According to one post the issue is limited to os-prober which would prevent https://wiki.archlinux.org/title/Microc … ly_loading and another one suggests that it's because of pre-2.04 grub versions. Your kernel panic might have been a result from a missing ucode update but I guess your ubuntu does not use grub 2.03 or lower?

Arch Linux

#1 2023-09-03 14:19:00

[SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

#2 2023-09-03 15:16:00

Re: [SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

#3 2023-09-03 15:24:11

Re: [SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

#4 2023-09-03 16:01:43

Re: [SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

#5 2023-09-03 18:06:05

Re: [SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

#6 2023-09-03 18:50:40

Re: [SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

#7 2023-09-03 19:01:06

Re: [SOLVED] Multiboot Ubuntu,Windows,Arch with Grub not detecting Arch

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