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kiriakos

Member

From: Germany

Registered: 2025-03-02

Posts: 4

Website

Missing md_mod kernel module in initcpio and only one initcpio

Hi there,

after running an upgrade (pacman -Syu) last week and rebooting I noticed two things.

1. I was dropped into a rescue shell because the initcpio could not find my luks volume on top of a raid (md_mod) was missing from the image.
2. Only one image was created (didn't we have a fallback image as a second option?)

My mkinitcpio.conf looks like this:

MODULES=(amdgpu radeon)
BINARIES=()
FILES=(/secret/typee-root.conf)
HOOKS=(base udev modconf keyboard keymap autodetect microcode block mdadm_udev encrypt filesystems fsck)

Adding md_mod to MODULES fixes the boot problem but it doesn't feel correct, shouldn't mdadm_udev take care of that?
Did I miss a config change?

---

$> man life
No manual entry for `life'

$> nvm...

frostschutz

Member

Registered: 2013-11-15

Posts: 1,637

Re: Missing md_mod kernel module in initcpio and only one initcpio

Well, of course it should work, but there is no harm in adding to MODULES. My own system had raid1 raid456 in MODULES from a long time ago, and it just worked for me, even with the known-to-be-buggy version. I'm definitely keeping it ;-)

Is it still broken when you remove it, though? mdadm updates don't trigger initcpio rebuilds (/usr/share/libalpm/hooks/90-mkinitcpio-install.hook has cryptsetup, lvm, but not mdadm triggers), so unless updated by something else, it was possible to still have affected mdadm version in the initcpio after update.

There was another thread https://bbs.archlinux.org/viewtopic.php?id=312555 where missing /bin/sh was somehow the problem, but it was systemd-based initcpio. It should not be possible in busybox-based initcpio... or maybe it was a different issue altogether, not sure.

Last edited by frostschutz (2026-03-11 11:03:44)