mkinitfs doesn't add dirname/readlink for mdev helpers
(Running Alpine Linux edge, roughly 3.3)
dirname and readlink are used in some of the mdev helpers, but mkinitfs does not add the commands to the initramfs by default.
This results in a rather messy boot when using mdev, with at least a pageful of ‘command not found’ messages here.
To confirm without rebooting, it’s possible to use this command:
for IRF in /boot/initramfs*; do echo “$IRF:” && zcat <“$IRF” | grep dirname ; done
If ‘dirname’ shows up in the path, mkinitfs does not have the bug.
I think the simple solution is to add these commands to /etc/mkinitfs/features.d/base.files.
(from redmine: issue id 4809, created on 2015-10-30, closed on 2017-04-07)