efistubmgr

A script for managing EFI boot entries that directly start Linux using the EFISTUB functionality of the kernel.

Dependencies

• A sufficiently POSIX-compliant shell at /bin/sh (bash will work)
• Various other POSIX tools, in $PATH or as shell built-ins: sed, printf, [, mkdir, echo, cat, sort, comm (you probably have these already)
• findmnt, from the util-linux package
• efibootmgr (get it from your distro's package manager if possible)

Prerequisites

The script searches in /boot for a config file and for microcode initrds. If it finds any microcode initrds, it assumes that /boot is the root directory of the system's EFI system partition.

The script writes the boot entries it manages to /var/lib/efistubmgr/managed_entries. If it can't create the directory or write the file, the script fails.

How to use

Make a file in /boot named efistubmgr.conf and add a valid configuration there (look in the "examples" directory for example configs).

Afterwards, run update-efi as root. The boot entries specified in the config file should now be added to the boot menu. You can verify this by running efibootmgr.

If you later edit the config file, run update-efi as root again to update the boot entries.