Bug#948257: depmod: ERROR: ../libkmod/libkmod.c:515 lookup_builtin_file() could not open builtin file '/var/tmp/mkinitramfs_XXXXXXX/lib/modules/5.4.0-1-amd64/modules.builtin.bin'

[Pierrick CHANTEUX]

Hello,

This bug resulted in complete system breakage and I couldn't boot
anymore (systemd failing to load Kernel modules). I can guarantee that
this isn't only cosmetic.

I believe this isn't related to initramfs-tools, because downgrading
kmod and libkmod2 from version 26+20191223-1 to version 26-3 fixes the
issue. Initramfs now build (and run) correctly.

Regards,
-- 
Pierrick CHANTEUX