History

Steve Baker 27a326dafb Support secure-boot bootloader where possible

As of grub2 >= 2.02-95 on redhat family distros, calling grub2-install
on an EFI partition will fail with: "this utility cannot be used for
EFI platforms because it does not support UEFI Secure Boot."

This version of grub is now in centos8-stream and non-eus repos of
RHEL-8. It is not currently possible to build whole-disk UEFI images
on these distros, and when this package is promoted this will also
affect centos8 and RHEL-8 eus. The grub maintainers made this change
because the grub2-install generated /boot/efi/EFI/BOOT/BOOTX64.EFI
will never be capable of booting with Secure Boot.

This change defines a $EFI_BOOT_DIR for every distro element. When
directory /boot/efi/$EFI_BOOT_DIR exists a grub.cfg file in will be
generated there. This change also installs the shim package on redhat
family distros, which installs a copy of the shim bootloader to
/boot/efi/EFI/BOOT/BOOTX64.EFI. Using centos as an example, this
allows UEFI to boot the shim /boot/efi/EFI/BOOT/BOOTX64.EFI which
then chains to /boot/efi/EFI/centos/grubx64.efi.

If /boot/efi/$EFI_BOOT_DIR doesn't exist (such as for Ubuntu,
/boot/efi/EFI/ubuntu) the current behaviour of running grub-install to
generate /boot/efi/EFI/BOOT/BOOTX64.EFI will continue. For distros
such as Ubutnu where packaging does not populate /boot/efi/EFI/ubuntu
with .efi files, secure boot can be added in the future by copying
.efi files to /boot/efi/EFI/ubuntu and copying the shim file to
/boot/efi/EFI/BOOT/BOOTX64.EFI.

Change-Id: I90925218ff2aa4c4daffcf86e686b6d98d6b0f21

2021-03-11 10:27:59 +13:00

cleanup.d

update grub cmdline to current kernel parameters

2020-06-14 00:39:42 -05:00

environment.d

update grub cmdline to current kernel parameters

2020-06-14 00:39:42 -05:00

finalise.d

Support secure-boot bootloader where possible

2021-03-11 10:27:59 +13:00

pkg-map

Support secure-boot bootloader where possible

2021-03-11 10:27:59 +13:00

README.rst

update grub cmdline to current kernel parameters

2020-06-14 00:39:42 -05:00

README.rst

bootloader

Installs grub[2] on boot partition on the system. In case GRUB2 is not available in the system, a fallback to Extlinux will happen. It's also possible to enforce the use of Extlinux by exporting a DIB_EXTLINUX variable to the environment.

Arguments

DIB_GRUB_TIMEOUT sets the grub menu timeout. It defaults to 5 seconds. Set this to 0 (no timeout) for fast boot times.
DIB_BOOTLOADER_DEFAULT_CMDLINE sets parameters that are appended to the GRUB_CMDLINE_LINUX_DEFAULT values in grub.cfg configuration. It defaults to nofb nomodeset gfxpayload=text.
DIB_BOOTLOADER_SERIAL_CONSOLE sets the serial device to be used as a console. It defaults to hvc0 for PowerPC, ttyAMA0,115200 for ARM64, otherwise ttyS0,115200.