The archiso mkinitcpio hooks live in initcpio/ at the repo root, not in
configs/releng/airootfs/ — so they were never in the ISO airootfs chroot.
ALARM has no archiso package either, so the chroot's mkinitcpio found no
archiso hook, built an initramfs without mount_handler logic, and the
default handler fired at boot with empty root= → "Failed to mount ''".
Dockerfile.arm64: preserve the official hooks from initcpio/ into
/usr/share/archiso/initcpio/ instead of deleting them with the repo.
entrypoint-arm64.sh: explicitly install the official hooks into the
airootfs overlay so the chroot mkinitcpio finds them when building the
initramfs. The official hooks use uname -m for arch detection and include
all required modules/binaries for squashfs live boot.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
nmemmertandClaude Sonnet 4.6
00c4914b7b