From d2050181d429e5f863ca0b173a83e95c131cac8d Mon Sep 17 00:00:00 2001
From: Dan Bungert <daniel.bungert@canonical.com>
Date: Thu, 27 Feb 2025 17:15:02 -0700
Subject: [PATCH] subiquity: easier bridge kernel setup
For subiquity installs, make it easier to enable bridge kernel, just a
boolean to set true/false. Don't enable yet though.
---
live-build/auto/config | 40 ++++++++++++++----------------------
live-build/functions | 36 ++++++++++++++++++++++++++++++++
live-build/lb_binary_layered | 3 ++-
3 files changed, 53 insertions(+), 26 deletions(-)
diff --git a/live-build/auto/config b/live-build/auto/config
index ddbe2970..ef279cb5 100755
--- a/live-build/auto/config
+++ b/live-build/auto/config
@@ -78,6 +78,14 @@ BINARY_HOOKS=
APT_OPTIONS=" --yes -oDebug::pkgDepCache::AutoInstall=yes "
+# Should we attempt to offer both the bridge and default kernel?
+USE_BRIDGE_KERNEL=false
+# Why are we using bridge kernel? Value is ignored for USE_BRIDGE_KERNEL=false.
+# Possible reasons are zfs, drivers.
+BRIDGE_KERNEL_REASONS="zfs,drivers"
+# When building install-sources, what kernel is the default?
+DEFAULT_KERNEL=
+
PASSES_TO_LAYERS=false
_PASSES_TO_LAYERS= # Stores the initial value of PASSES_TO_LAYERS
PASSES=
@@ -240,28 +248,6 @@ add_snap ()
done
}
-write_kernel_yaml () {
- # Generate the kernel.yaml fragment used as input for
- # update-source-catalog. Handles default kernel specification.
- # $1 kernel metapackage name
- local metapkg="$1"
- cat <<-EOF > config/kernel.yaml
- kernel:
- default: "$metapkg"
- EOF
-
- # To specify fallback to a bridge kernel, construct a kernel.yaml
- # with the following:
- #
- # kernel:
- # default: foo
- # bridge: bar
- # bridge_reasons: [zfs, drivers]
- #
- # If an install is using zfs or "drivers", use the bridge kernel, else
- # use the default kernel.
-}
-
get_seeded_languages () {
# We assume any seed name of the form ${no_lang_seed}-${foo} where
# ${foo} is only two or three characters long is a default language
@@ -812,7 +798,7 @@ do_layered_desktop_image() {
EOF
fi
- write_kernel_yaml "linux-$KERNEL_FLAVOURS"
+ DEFAULT_KERNEL="linux-$KERNEL_FLAVOURS"
if [ "$LOCALE_SUPPORT" != none ]; then
/usr/share/livecd-rootfs/checkout-translations-branch \
@@ -1105,7 +1091,7 @@ case $PROJECT in
esac
NO_SQUASHFS_PASSES=ubuntu-server-minimal.ubuntu-server.installer.$flavor.netboot
- write_kernel_yaml $kernel_metapkg
+ DEFAULT_KERNEL="$kernel_metapkg"
/usr/share/livecd-rootfs/checkout-translations-branch \
https://git.launchpad.net/subiquity po config/catalog-translations
;;
@@ -1133,7 +1119,8 @@ case $PROJECT in
add_package base.live linux-image-generic
# Core installer images use the pc-kernel snap for its kernel
- write_kernel_yaml "snap:pc-kernel"
+ USE_BRIDGE_KERNEL=false
+ DEFAULT_KERNEL="snap:pc-kernel"
/usr/share/livecd-rootfs/checkout-translations-branch \
https://git.launchpad.net/subiquity po config/catalog-translations
@@ -1399,6 +1386,9 @@ echo "BUILDSTAMP=\"$NOW\"" >> config/binary
echo "SUBPROJECT=\"${SUBPROJECT:-}\"" >> config/binary
echo "LB_DISTRIBUTION=\"$SUITE\"" >> config/binary
echo "CHANNEL=\"${CHANNEL:-}\"" >> config/binary
+echo "USE_BRIDGE_KERNEL=\"${USE_BRIDGE_KERNEL:-}\"" >> config/binary
+echo "BRIDGE_KERNEL_REASONS=\"${BRIDGE_KERNEL_REASONS:-}\"" >> config/binary
+echo "DEFAULT_KERNEL=\"${DEFAULT_KERNEL:-}\"" >> config/binary
if [ "${IMAGE_HAS_HARDCODED_PASSWORD:-}" = "1" ]; then
echo IMAGE_HAS_HARDCODED_PASSWORD=1 >> config/binary
diff --git a/live-build/functions b/live-build/functions
index 39d53971..4f26e087 100644
--- a/live-build/functions
+++ b/live-build/functions
@@ -1337,3 +1337,39 @@ reset_snapd_state() {
chroot "$rootdir" apt-get install --reinstall -y snapd
teardown_mountpoint "$rootdir"
}
+
+write_kernel_yaml() {
+ # Generate the kernel.yaml fragment used as input for
+ # update-source-catalog.
+ #
+ # the newer kernel is the default kernel!
+ # bridge is the older, fallback kernel.
+ # $1 string, default kernel, such as "linux-generic"
+ # $2 string with comma seperated list of bridge reasons,
+ # usually "zfs,drivers"
+ local default="$1"
+ local reasons="$2"
+
+ cat <<EOF > config/kernel.yaml
+kernel:
+ default: "$default"
+EOF
+
+ # To specify fallback to a bridge kernel, construct a kernel.yaml
+ # with the following:
+ #
+ # kernel:
+ # default: linux-foo
+ # bridge: linux-foo-brg-YY.MM
+ # bridge_reasons: [zfs, drivers]
+ #
+ # If an install is using zfs or "drivers", use the bridge kernel, else
+ # use the default kernel.
+
+ if $USE_BRIDGE_KERNEL ; then
+ cat <<EOF >> config/kernel.yaml
+ bridge: "${default}-brg-$(release_ver)"
+ bridge_reasons: [$reasons]
+EOF
+ fi
+}
diff --git a/live-build/lb_binary_layered b/live-build/lb_binary_layered
index e64ecaee..75dfe9c7 100755
--- a/live-build/lb_binary_layered
+++ b/live-build/lb_binary_layered
@@ -204,7 +204,8 @@ do
build_layered_squashfs "${_PASS}" ${*}
done
-if [ -f config/kernel.yaml ]; then
+if [ -n "$DEFAULT_KERNEL" -a -f livecd.${PROJECT_FULL}.install-sources.yaml ]; then
+ write_kernel_yaml "$DEFAULT_KERNEL" "$BRIDGE_KERNEL_REASONS"
/usr/share/livecd-rootfs/update-source-catalog merge \
--output livecd.${PROJECT_FULL}.install-sources.yaml \
--template config/kernel.yaml