When installing a distro via EFI HTTP boot some OS installers expect the .iso image to be preserved and treat it as a "CDROM" to install packages.
This is problematic in EFI, since U-Boot mounts the image, starts the installer, and eventually calls ExitBootServices. At that point the image U-Boot mounted disappears. Some distros don't care and download the missing packages from a web archive, while others halt the installation complaining they can't find certain packages.
If the firmware uses ACPI, this is supported by using NFIT which provides NVDIMM ramdisks to the OS and preserves the image. We don't have anything in place for Device Trees though. Since DT supports persistent memory nodes (pmem) use those and preserve the .iso for installers.
The issue can be reproduced by attempting an EFI HTTP boot with Ubuntu live server ISO, or a Rocky Linux ISO. The installation would fail with the failure to locate certain packages.
Ilias Apalodimas (2): efi_loader: add a function to remove memory from the EFI map efi_loader: preserve installer images in pmem
Masahisa Kojima (1): fdt: add support for adding pmem nodes
Sughosh Ganu (1): efi: add helper functions to insert pmem node for DT fixup
boot/fdt_support.c | 41 +++++++++++++++++++++++++++-- boot/image-fdt.c | 9 +++++++ include/efi_loader.h | 28 +++++++++++++++++--- include/fdt_support.h | 13 +++++++++ lib/efi_loader/efi_bootmgr.c | 43 ++++++++++++++++++++++++++---- lib/efi_loader/efi_helper.c | 12 +++++++++ lib/efi_loader/efi_memory.c | 51 +++++++++++++++++++++++++++--------- lib/lmb.c | 4 +-- 8 files changed, 175 insertions(+), 26 deletions(-)