Fedora UEFI Live images (re)create boot entry

[ignatenkobrain]

Problem description

Building Fedora image with following image type/bootloader, every time I boot it on a real system, it (re)creates a boot entry in EFI leading to very useless entries in the UEFI.

<type image="iso" primary="true" flags="overlay" firmware="uefi" hybridpersistent="false"/>

❯ sudo efibootmgr -v | grep Fedora
Boot0000* Fedora	HD(1,GPT,4d16e6d9-001c-460f-be90-59cdb1ef74fc,0x800,0x12c000)/File(\EFI\fedora\shimx64.efi)
Boot0002* Fedora	PciRoot(0x0)/Pci(0x14,0x0)/USB(13,0)/CDROM(1,0x207fc8,0x28000)/File(\EFI\fedora\shimx64.efi)
Boot0003* Fedora	PciRoot(0x0)/Pci(0x14,0x0)/USB(13,0)/CDROM(1,0x267210,0x28000)/File(\EFI\fedora\shimx64.efi)

I believe shim invokes fallback as described here https://github.com/rhboot/shim/blob/main/README.fallback.

If I understand the documentation correctly, Live systems are not supposed to have /boot/fedora at all and use /boot/EFI only but that's not what kiwi is producing.

For comparison, official Fedora Live image has:

media/brain/Fedora-WS-Live-35-1-2 
❯ find EFI -type f
EFI/BOOT/BOOT.conf
EFI/BOOT/BOOTIA32.EFI
EFI/BOOT/BOOTX64.EFI
EFI/BOOT/fonts/unicode.pf2
EFI/BOOT/grub.cfg
EFI/BOOT/grubia32.efi
EFI/BOOT/grubx64.efi
EFI/BOOT/mmia32.efi
EFI/BOOT/mmx64.efi

while what kiwi is producing:

[root@powerful-box tmp]# find EFI -type f
EFI/BOOT/BOOTX64.EFI
EFI/BOOT/bootx64.efi
EFI/BOOT/fbx64.efi
EFI/BOOT/grub.cfg
EFI/BOOT/grubx64.efi
EFI/BOOT/mmx64.efi
EFI/fedora/BOOTX64.CSV
EFI/fedora/grub.cfg
EFI/fedora/grubx64.efi
EFI/fedora/mmx64.efi
EFI/fedora/shim.efi
EFI/fedora/shimx64.efi

Expected behaviour

No entries are added on boot.

Steps to reproduce the behaviour

Build Fedora (35) image in Live ISO mode with UEFI support (as described in the kiwi-descriptions repo, just modify slightly). Then boot it on a real laptop (possibly with secure boot enabled?).

OS and Software information

• KIWI version: 9.24.15
• Operating system: Fedora 35
• OBS version: N/A

[ignatenkobrain]

I've tried to figure out how lorax (the thing that produces Fedora images) is handling this and it seems that https://github.com/weldr/lorax/blob/fa2e465d51039e6172e5118c432b715316a70a48/share/templates.d/99-generic/live/efi.tmpl is relevant piece of code there.

Also from other places, it seems it just packs EFI/BOOT only, not anything else in the EFI folder.

[ignatenkobrain]

@schaefi ^^ as we were briefly touching this topic on the Matrix.

[schaefi]

Thanks for the details. You are right kiwi does differentiate the vendor setup for grub between a live image and any other type of image. We can change this.

I wonder about the contents of EFI/BOOT/BOOT.conf this file is new to me in the context of EFI boot and not created by kiwi at all. Can you provide details for what it is good for ? Maybe the contents ?

I think @Conan-Kudo wrote a good junk of all the live CD tools for Fedora, so he also should know what kiwi needs to do differently

Thanks

[Conan-Kudo]

Most of the stuff that's been done with the bootloader stuff in the past few years in Fedora have been done by @martinezjavier.