Upgrade to omarchy 3.4.0 broke mdadm raid

[med502]

System details

Omarchy 3.4.0

What's wrong?

Not sure if this is release issue or kernel upgrade issue.
After upgrade my system crashed on kernel panic due to raid timing out.

Looks like md_mod module was no longer loaded at boot which made mdadm unusable.
Maybe below steps will help someone

Steps I made to fix and find issue

1. Logged as root to recovery mode
2. Commented out raid entries in /etc/fstab
3. Reboot and logged into system normally
   I tried to re-assemble raid

sudo mdadm --assemble --scan

which failed with

mdadm: Can't open /sys/module/md_mod/parameters/legacy_async_del_gendisk
mdadm: init md module parameters fail
mdadm: No arrays found in config file or automatically

4. Changed config /etc/mkinitcpio.conf
   by removing nvidia modules (I had Nvidia card but switched to AMD few months ago)
   uncommenting module for mdadm
5. ran mkinitcpio -v -p linux which failed with

Using default configuration file: '/etc/mkinitcpio.conf' -> -k /boot/vmlinuz-linux -g /boot/initramfs-linux-fallback.img -S autodetect
ERROR: Invalid option -g -- '/boot/initramfs-linux-fallback.img' must be writable

I had to do this to fix it

> pacman -Rscn linux # Probably not necessary, but I did it out of habit.
> rm /etc/mkinitcpio.d/linux.preset.pacsave
> pacman -Syu linux
> mv /etc/mkinitcpio.conf.bak /etc/mkinitcpio.conf
> mkinitcpio -p linux

source https://bbs.archlinux.org/viewtopic.php?pid=1925244#p1925244

6.Commadn to fix missing module

echo "md_mod" | sudo tee /etc/modules-load.d/md_mod.conf

7. mdamd started working and I could re-assemble raid and uncomment raid entry in /etc/fstab
8. systemctl daemon-reload to load module
9. sudo mount -a to mount

--- formating edit

[dhh]

We didn't change anything here on the Omarchy side. So I'm guessing it is indeed a kernel change or something else in the deeper dependencies.

[avenkidur]

I had the same issue.
There was a problem in the initial release of mdadm 4.5, which snuck through the Arch testing/release process.

See #4758 for instructions on how to restore your raid pool