Our images are built with build.neon.kde.org using the scripts in pangea-tooling nci/imager imager.rb starts a new containment and runs build.sh and copies the result depot and images.neon.kde.org
build.sh is run in the containment and installs the packages needed, sets some variables and runs ubuntu-defaults-image
ubuntu-defaults-image is a script copied from ubuntu-defaults-builder, an Ubuntu script intended to make locale specific ubuntu derived images (we ignore the template for meta package and locale stuff).
It uses Ubuntu’s fork of Debian’s live-build, it’s quite an old fork (3.0~ from August 2012) with lots of Ubuntu specific patches
live-build uses livecd-rootfs, Ubuntu hooks (/usr/share/livecd-rootfs/live-build/ubuntu-core/) to build the squashfs live filesystem
Our meta packages and ISOs are made from Seeds
live-build does not support UEFI. There's a few patches and addons to do so, see todo item for links.
The live-build UEFI bug has patches to add it natively. Netrunner just keeps it from Kubuntu as part of the remaster. Tanglu adds a efi script to live-build which takes it from debian-installer.
Ubuntu images get their livefs built on Launchpad (using a not very well documented and somewhat incomplete coded part of Launchpad which I think it only useable by this team for this purpose) https://launchpad.net/~ubuntu-cdimage/+livefs/ubuntu/xenial/kubuntu/ which are seem to be built with livefs-rootfs (says launchpad code ./lib/lp/soyuz/templates/livefs-new.pt).
Then the ISO images are made by some magic proprietary script which takes the live image and adds its own stuff including UEFI support. http://people.canonical.com/~ubuntu-archive/cd-build-logs/kubuntu/xenial/
ISO booting by UEFI support is done by copying the grub-efi files from a Kubuntu ISO, putting them in live-build and in the lb efi script copying it into the binary/ directory and extracting the efi images (with mcopy) to add the right files on the CD. The breeze-grub theme is added and boot name changed to Neon in grub.cfg.
For UEFI support on installed systems Ubiquity needs a local apt archive on the CD image which contains grub-efi, we again grab a copy of this from Kubuntu images. It also needs a file called .disk/cd_type.
Ubiquity installs the EFI files into /boot/EFI/efi/neon on the installed system but the path "efi/ubuntu" is hardcoded in two places. The fwup efi binary which is used for firmware updates installs to efi/ubuntu and the Grub efi binary is hardcoded to look in efi/ubuntu for grub.cfg so a patch in ubiquity copies our grub.cfg into efi/ubuntu (this patch need to be applied manually in the archive as the package is native not quilt). This has the downside that any changes in the ubuntu grub.cfg will get removed, similarly a later Ubuntu install will wipe the neon grub.cfg but as the code to set up grub.cfg is the same for both having a custom config which differs is a very niche setup.
The shim, grub and linux binaries are all copied directly from Kubuntu and signed with that so this just works. If we want to make changes such as not hard coding efi/ubuntu in the grub binary we'd need to build it ourselves, sign up to Microsoft's approval scheme. This is left as future work.
How this works with GPL 3 terms is another mystery for future work.
We're also building images for the Pinebook cheap ARM-based laptop.
As of Decemeber 2017 we have built all of dev-unstable packages for ARM64 architecture.
img_neon_xenial_devedition-gitunstable_arm64 build job will produce a .img disk image which can be dd'ed to a microSD card and booted up on Pinebook.
Code to create image is in pangea-tooling.
Unlike the ISO images which use live-build from Ubuntu this uses live-build from Debian. The images get made in Docker on master (Drax) amd64 server using QEMU to emulate arm, this is slow but necessary because we use process namespacing on our arm64 Docker setup for security.
Similarly we use live-config from Debian rather than Casper from Ubuntu as this works in normal user-space while Casper needs faff with initramdisks.
There are 3 custom parts:
We install Linux and Mali from Netrunner repos and build armsoc driver ourselves.