Arch Linux

Hanabishi

Member

Registered: 2020-08-07

Posts: 30

Re: Systemd-boot on btrfs /boot

but for the case as you describe it I'd just try to set the XBOOTLDR GUID

I actually tried that. I marked my root partition as XBOOTLDR and placed a filesystem driver (btrfs_x64.efi) into EFI/systemd/drivers/ of ESP partition.
But unfortunately it does not work. At least with Btrfs that I tried. Systemd-boot does not pick it up for some reason.

Even if it would have worked tough, I see some disadvantages:
1. Despite the kernel does not care about the partition type, changing the root partition type to anything other than "Linux root" breaks Systemd GPT partition automounting capability.
2. GUI file managers treat XBOOTLDR as a hidden partition.

Last edited by Hanabishi (2023-11-09 11:55:12)

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

but for the case as you describe it I'd just try to set the XBOOTLDR GUID

I actually tried that. I marked my root partition as XBOOTLDR and placed a filesystem driver (btrfs_x64.efi) into EFI/systemd/drivers/ of ESP partition.
But unfortunately it does not work. At least with Btrfs that I tried. Systemd-boot does not pick it up for some reason.

Did you place your /boot on a subvolume or root volume?
- If you placed it on root volume, /boot directory won't work as systemd-boot looks for /loader/entries/*.conf files. So you have to place your boot entries files to the path without /boot prefix in this case.
- If you placed it on subvolume, that subvolume should probably set as default with "btrfs subvolume set-default", as otherwise again - the path would include /boot and systemd-boot knows nothing about it on boot.

Could you retest?

Last edited by bam (2024-03-13 13:44:20)

Hanabishi

Member

Registered: 2020-08-07

Posts: 30

Re: Systemd-boot on btrfs /boot

I am aware of the layout. No /boot subdir, no subvolumes for it. Loader entires and kernel images were placed directly into root of the partition, exactly the same as on a real boot partition.

I.e. in terms of the default system layout it is effectively

cp -r /boot -T /

So there is nothing to retest unfortunately.

Last edited by Hanabishi (2024-03-13 14:07:26)

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

If you wish to experiment with it a bit more, could you check if your btrfs driver actually works?
Can you see you filesystem from UEFI shell?

PS:
I had problem even with ext4, so maybe something wrong with btrfs compatibility..

Last edited by bam (2024-03-14 01:36:10)

Hanabishi

Member

Registered: 2020-08-07

Posts: 30

Re: Systemd-boot on btrfs /boot

Yeah, with the driver present I can see the root content as FS1.
I think it is simpler to just analyze systemd-boot source, maybe we miss something.

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

I would report about the problem first. Maybe it's known.

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

Did you read Notes here?
https://wiki.archlinux.org/title/System … g_XBOOTLDR

Also, worth trying on VM.

Hanabishi

Member

Registered: 2020-08-07

Posts: 30

Re: Systemd-boot on btrfs /boot

Yup. I even contributed to this article.

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

I would report about the problem first. Maybe it's known.

https://github.com/rhinstaller/anaconda … 2692747834

Please chime in anyone interested.

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

Oops, wrong link,
https://github.com/systemd/systemd/pull … 2694213300

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

Actual report:
sd-boot: can't boot from BTRFS XBOOTLDR

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 8,842

Website

Re: Systemd-boot on btrfs /boot

Sanity check: were the configuration files on the XBOOTLDR partition?

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Jin, Jîyan, Azadî

bam

Member

Registered: 2022-01-03

Posts: 10

Re: Systemd-boot on btrfs /boot

"boot/loader/entries" it seems:
https://github.com/poettering/mkosi/blo … kosi#L1078

Last edited by bam (2025-03-03 16:02:40)