openstack
/
diskimage-builder
Code Issues Proposed changes
diskimage-builder/diskimage_builder/elements/bootloader
History
Clark Boylan 3294aecca2 Properly set grub2 root device when using efi 
We've noticed that centos8 arm64 images have a root devices of
/dev/mapper/loop7p3 which make sense within a dib image build context
but not at boot time. Dib intends to use labels to set the root device
but when efi is used we end up running grub2-mkconfig against the efi
grub config path before we configure grub to use labels.

Fix this by running grub2-mkconfig after its configuration is set.
This should avoid confusion and complicated paths through the scripts
that configure this for us. We then copy the resulting config to the efi
specific grub.cfg location for platforms that have it.

There is also a small refactoring that is done to try and make the ~3
boot variants more clear:

 1) Booting with legacy bios
 2) Booting with uefi without a signed shim that directly calls grub
 3) Booting with uefi and a signed shim that calls grub

Options 1 and 2 share the /boot/grub*/grub.cfg file. Option 3 needs its
grub.cfg to live alongside distro specific efi target.

Change-Id: Ie9790da9d1bbea58197b37b15a48e77f8a93c1ac
 		2021-04-07 15:46:10 -07:00
..
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 Properly set grub2 root device when using efi 2021-04-07 15:46:10 -07:00
README.rst update grub cmdline to current kernel parameters 2020-06-14 00:39:42 -05:00
pkg-map Support secure-boot bootloader where possible 2021-03-11 10:27:59 +13:00

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.