Failed to open \EFI\BOOT\mmx64.efi - Not found

[panotjk]

When boot from Linux Mint ISO or USB drive written with ISO image, the boot program loaded by UEFI firmware is shim. If there are pending MOK enroll/delete/reset, shim will have to load MokManager from \EFI\BOOT\mmx64.efi. But Linux Mint ISO and its FAT partition do not have \EFI\BOOT\mmx64.efi. There is this error message.

Failed to open \EFI\BOOT\mmx64.efi - Not Found
Failed to load image ??: Not Found
Failed to start MokManager: Not Found
Something has gone seriously wrong: import_mok_state() failed: Not Found

How to reproduce error:

• Set boot mode to UEFI. Turn on secure boot (and reset secure boot keys and load default platform key). Boot Linux Mint USB (or DVD or ISO in VirtualBox). Run "Install Linux Mint" with "Install multimedia codecs" on, configure secure boot, set password, continue. At the installation type page (Erase disk ... Something else), quit installation. (At this time, sudo mokutil --list-new shows a key waiting to be enrolled on next boot.) Shutdown/Restart. Insert Linux Mint USB drive (or DVD/ISO) and open firmware boot menu. Try to boot Linux Mint Live USB (or DVD/ISO) again. Error.

Compare to older versions:

• 21.3, 22.1 also do not have \EFI\BOOT\mmx64.efi

Compare to other distro:

• Ubuntu 24.04.3 LTS (server/desktop) ISOs have \EFI\BOOT\mmx64.efi.

After running MokManager from Ubuntu Live USB drive to process the pending MOK enroll/delete/reset, shim no longer loads MokManager and Linux Mint Live USB can boot again.

Suggestion:

• Add MokManager to EFI/boot/mmx64.efi in boot/grub/efi.img, FAT partition and ISO file system in Linux Mint ISO.