option to load addition kernel modules (btrfs boot support)

[MartinNowak]

Hello, tried to switch the root FS of my ARM64-2GB server to btrfs (using btrfs-convert).
It seems that the initial kernel lacks the btrfs.ko module to mount that FS.

Any chance, that additional modules could be loaded on demand, e.g. via a dedicated environment option

INITRD_MODULES=fs/btrfs/btrfs.ko,<mod>

.

This approach here also relies on manually loading missing modules before continuing the boot.
Btrfs image : a recipe - Scaleway / Tutorials

[MartinNowak]

Also see scaleway/image-builder#12

[berezins]

May be my solution with partitioning (using small partition for root and everything else for any file system of your choice and/or LVM) would solve your case (my last answer in scaleway/image-builder#12)

[MartinNowak]

Yes, a separate partition should be feasible, but it classically becomes a pain when root runs out of space.
Given that there already is a function for that

initrd/Linux/tree-common/functions

Lines 210 to 215 in 51c564e

	load_btrfs_ko() {
	insmod_ko crypto/xor.ko
	insmod_ko lib/raid6/raid6_pq.ko
	insmod_ko lib/zlib_deflate/zlib_deflate.ko
	insmod_ko fs/btrfs/btrfs.ko
	}

, it shouldn't be too hard to make it available for non-live boots.

initrd/Linux/tree-common/boot-live

Line 15 in 87bcaec

load_btrfs_ko