debian-bookworm-build already adds a user (as it is a combination of debian-bullseye-build and debian-bullseye-jenkins, and the latter did it). Remove the additional useradd in osmo-uecups-master to fix:
useradd: UID 1000 is not unique
I've looked through related configs and scripts and the username is not hardcoded there.
The initramfs filesystem layout is derived from the paths of the binaries and libraries in the full system. Create the same symlinks and adjust initrd_add_bin so it does not trip over the symlinks.
I've also considered to change all input for initrd_add_bin to point at the /usr/… paths. But this is not possible, for example ldd/lddtree will point at libraries in /lib and /lib64, and this gets passed to initrd_add_bin.
Without this patch, the init script and all binaries called from it cannot be executed.
Set init= so the kernel doesn't try to run other scripts if /init fails:
[ 2.946381] Run /init as init process [ 2.948885] Failed to execute /init (error -2) [ 2.949051] Run /sbin/init as init process [ 2.949329] Run /etc/init as init process [ 2.949566] Run /bin/init as init process [ 2.949795] Run /bin/sh as init process
