05core: add coreos-ignition-delete-config.service for upgrade boots

overlay.d/05core/usr/lib/systemd/system-preset/40-coreos.preset

@@ -10,6 +10,8 @@ enable coreos-ignition-firstboot-complete.service
 # Delete Ignition config from provider on platforms where it's possible
 # https://github.com/coreos/ignition/pull/1350
 enable ignition-delete-config.service
+# Delete Ignition config from provider when upgrading existing nodes
+enable coreos-ignition-delete-config.service
 # Boot checkin services for cloud providers.
 enable afterburn-checkin.service
 enable afterburn-firstboot-checkin.service

overlay.d/05core/usr/lib/systemd/system/coreos-ignition-delete-config.service

@@ -0,0 +1,28 @@
+# Can be removed from FCOS in Fedora 37 or after the next barrier release,
+# whichever comes first.  Can be removed from RHCOS in the first release
+# after every node is guaranteed to have booted at least once with 4.11 or
+# higher.
+
+[Unit]
+Description=CoreOS Delete Ignition Config From Hypervisor
+Documentation=https://coreos.github.io/ignition/
+
+ConditionKernelCommandLine=|ignition.platform.id=virtualbox
+ConditionKernelCommandLine=|ignition.platform.id=vmware
+ConditionPathExists=!/var/lib/coreos-ignition-delete-config.stamp
+# Hack: if the user masked ignition-delete-config.service, we shouldn't run
+# either.
+ConditionPathIsSymbolicLink=!/etc/systemd/system/ignition-delete-config.service
+
+# We check a stamp file written by ignition-delete-config.service.  That
+# service runs Before=sysinit.target, on which we have a default dependency,
+# so this is really just documentation.
+After=ignition-delete-config.service
+
+[Service]
+Type=oneshot
+ExecStart=/usr/libexec/coreos-ignition-delete-config
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target

overlay.d/05core/usr/lib/systemd/system/ignition-delete-config.service.d/10-flag-file.conf

@@ -0,0 +1,7 @@
+# Create a flag file to notify coreos-ignition-delete-config.service that
+# we've run, and put it in /run because /var isn't mounted yet.
+# coreos-ignition-delete-config.service will then avoid trying to delete
+# the config again, and will create a persistent stamp file in /var/lib.
+
+[Service]
+ExecStart=/bin/touch /run/coreos-ignition-delete-config.stamp

overlay.d/05core/usr/libexec/coreos-ignition-delete-config

@@ -0,0 +1,23 @@
+#!/bin/bash
+
+set -euo pipefail
+
+cmdline=( $(</proc/cmdline) )
+cmdline_arg() {
+    local name="$1" value
+    for arg in "${cmdline[@]}"; do
+        if [[ "${arg%%=*}" == "${name}" ]]; then
+            value="${arg#*=}"
+        fi
+    done
+    echo "${value}"
+}
+
+# Avoid running again if ignition-delete-config.service has run, but still
+# create our own stamp file now that /var is mounted.
+if [ ! -e /run/coreos-ignition-delete-config.stamp ]; then
+    PLATFORM_ID=$(cmdline_arg ignition.platform.id)
+    /usr/libexec/ignition-rmcfg --platform=${PLATFORM_ID}
+fi
+
+touch /var/lib/coreos-ignition-delete-config.stamp

tests/kola/ignition/delete-config/config.bu

@@ -0,0 +1,36 @@
+variant: fcos
+version: 1.4.0
+storage:
+  files:
+    - path: /etc/fake-ignition-rmcfg
+      mode: 0755
+      contents:
+        inline: |
+          #!/bin/bash
+          # Mocked replacement for ignition-rmcfg that just records that
+          # we ran it, and fails if we run it twice.  We can't run
+          # ignition-rmcfg directly because it doesn't succeed on any
+          # platform we test on.
+          if [ -e /run/ignition-rmcfg-ran ]; then
+              echo "ignition-rmcfg ran twice"
+              exit 1
+          fi
+          touch /run/ignition-rmcfg-ran
+systemd:
+  units:
+    - name: ignition-delete-config.service
+      dropins:
+        - name: 50-kola.conf
+          contents: |
+            [Unit]
+            ConditionKernelCommandLine=|ignition.platform.id=qemu
+            [Service]
+            ExecStartPre=mount --bind /etc/fake-ignition-rmcfg /usr/libexec/ignition-rmcfg
+    - name: coreos-ignition-delete-config.service
+      dropins:
+        - name: 50-kola.conf
+          contents: |
+            [Unit]
+            ConditionKernelCommandLine=|ignition.platform.id=qemu
+            [Service]
+            ExecStartPre=mount --bind /etc/fake-ignition-rmcfg /usr/libexec/ignition-rmcfg

tests/kola/ignition/delete-config/data/commonlib.sh

@@ -0,0 +1 @@
+../../../data/commonlib.sh

tests/kola/ignition/delete-config/test.sh

@@ -0,0 +1,88 @@
+#!/bin/bash
+# kola: { "platforms": "qemu-unpriv" }
+# - platforms: qemu-unpriv
+#   - Ideally we'd test on virtualbox and vmware, but we don't have tests
+#     there, so we mock specifically for ignition.platform.id=qemu
+
+set -xeuo pipefail
+
+. $KOLA_EXT_DATA/commonlib.sh
+
+case "${AUTOPKGTEST_REBOOT_MARK:-}" in
+"")
+    # Ignition boot
+
+    if [ ! -e /run/ignition-rmcfg-ran ]; then
+        fatal "mocked ignition-rmcfg did not run on first boot"
+    fi
+
+    if [ $(systemctl is-active ignition-delete-config ||:) != active ]; then
+        fatal "ignition-delete-config didn't succeed on first boot"
+    fi
+    if [ $(systemctl is-active coreos-ignition-delete-config ||:) != active ]; then
+        fatal "coreos-ignition-delete-config didn't succeed on first boot"
+    fi
+    ok "First boot OK"
+
+    # Reset state and reboot
+    rm /var/lib/coreos-ignition-delete-config.stamp
+    /tmp/autopkgtest-reboot upgrade
+    ;;
+
+upgrade)
+    # Simulated upgrade from Ignition < 2.14.0
+
+    if [ ! -e /run/ignition-rmcfg-ran ]; then
+        fatal "mocked ignition-rmcfg did not run on upgrade boot"
+    fi
+
+    if [ $(systemctl is-active ignition-delete-config ||:) != inactive ]; then
+        fatal "ignition-delete-config ran on upgrade boot"
+    fi
+    if [ $(systemctl is-active coreos-ignition-delete-config ||:) != active ]; then
+        fatal "coreos-ignition-delete-config didn't succeed on upgrade boot"
+    fi
+    ok "Upgrade boot OK"
+
+    /tmp/autopkgtest-reboot steady-state
+    ;;
+
+steady-state)
+    # Steady-state boot; nothing should run
+
+    if [ -e /run/ignition-rmcfg-ran ]; then
+        fatal "mocked ignition-rmcfg ran on steady-state boot"
+    fi
+
+    if [ $(systemctl is-active ignition-delete-config ||:) != inactive ]; then
+        fatal "ignition-delete-config ran on steady-state boot"
+    fi
+    if [ $(systemctl is-active coreos-ignition-delete-config ||:) != inactive ]; then
+        fatal "coreos-ignition-delete-config ran on steady-state boot"
+    fi
+    ok "Steady-state boot OK"
+
+    # Reset state for masked unit and reboot
+    rm /var/lib/coreos-ignition-delete-config.stamp
+    systemctl mask ignition-delete-config.service
+    /tmp/autopkgtest-reboot masked
+    ;;
+
+masked)
+    # Simulated upgrade with masked ignition-delete-config.service
+
+    if [ -e /run/ignition-rmcfg-ran ]; then
+        fatal "mocked ignition-rmcfg ran on masked boot"
+    fi
+
+    if [ $(systemctl is-active ignition-delete-config ||:) != inactive ]; then
+        fatal "ignition-delete-config ran on masked boot"
+    fi
+    if [ $(systemctl is-active coreos-ignition-delete-config ||:) != inactive ]; then
+        fatal "coreos-ignition-delete-config ran on masked boot"
+    fi
+    ok "Masked unit OK"
+    ;;
+
+*) fatal "unexpected mark: ${AUTOPKGTEST_REBOOT_MARK}" ;;
+esac