start_image() returned 0x8000000000000001

When using Calamares 3.3.x series and choosing BTRFS as rootfs filesystem, the resulting installation may error out with start_image() returned 0x8000000000 within grub. Seems the amd-microcode image has an issue to properly load. Using the same install image but installing calamares5 package will result in a working installation with same rootfs settings. Editing the grub entry by removing /@/boot/amd-ucode.img let the image boot.

Similar issues were reported on other projects too:

You can prevent Grub from doing this by setting this option in /etc/default/grub: GRUB_EARLY_INITRD_LINUX_STOCK='' Using sudo lsinitrd -m /boot/initramfs-6.12-x86_64.img can check if there is an embedded microcode in the initramfs image. In our case there isn't.

An example for that would be:

# lsinitrd -m /boot/initramfs-linux.img

Image: /boot/initramfs-linux.img: 101M
========================================================================
Early CPIO image
========================================================================
drwxr-xr-x   1 root     root            0 Apr 22 21:07 .
-rw-r--r--   1 root     root            2 Apr 22 21:07 early_cpio
drwxr-xr-x   1 root     root            0 Apr 22 21:07 kernel
drwxr-xr-x   1 root     root            0 Apr 22 21:07 kernel/x86
drwxr-xr-x   1 root     root            0 Apr 22 21:07 kernel/x86/microcode
-rw-r--r--   1 root     root        39172 Apr 22 21:07 kernel/x86/microcode/AuthenticAMD.bin
========================================================================
Version: dracut-101

dracut modules:
systemd
systemd-initrd
i18n
btrfs
crypt
dm
kernel-modules
kernel-modules-extra
btrfs-snapshot-overlay
rootfs-block
terminfo
udev-rules
dracut-systemd
usrmount
base
fs-lib
shutdown
========================================================================

However it seems to have issues regardless of being embedded.