[PATCH v4 4/4] automation: add x86-64 livepatching test

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

Introduce a new gitlab tests for livepatching, using livepatch-build-tools,
which better reflects how downstreams build live patches rather than the
in-tree tests.

The tests applies the dummy in-tree patch example, checks that the patch is
applied correctly and then reverts and unloads it.

Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
---
Changes since v2:
 - Split livepatch build into a separate script.
---
 automation/gitlab-ci/build.yaml               |  9 +++
 automation/gitlab-ci/test.yaml                |  8 +++
 automation/scripts/build-livepatch            | 27 ++++++++
 .../scripts/qemu-alpine-x86_64-livepatch.sh   | 68 +++++++++++++++++++
 4 files changed, 112 insertions(+)
 create mode 100755 automation/scripts/build-livepatch
 create mode 100755 automation/scripts/qemu-alpine-x86_64-livepatch.sh

diff --git a/automation/gitlab-ci/build.yaml b/automation/gitlab-ci/build.yaml
index 32af30ccedc9..d770bffb845e 100644
--- a/automation/gitlab-ci/build.yaml
+++ b/automation/gitlab-ci/build.yaml
@@ -358,6 +358,15 @@ alpine-3.18-gcc-debug:
   variables:
     CONTAINER: alpine:3.18
 
+alpine-3.18-gcc-livepatch:
+  extends: .gcc-x86-64-build
+  script:
+    - ./automation/scripts/build-livepatch 2>&1 | tee build.log
+  variables:
+    CONTAINER: alpine:3.18
+    EXTRA_XEN_CONFIG: |
+      CONFIG_LIVEPATCH=y
+
 debian-stretch-gcc-debug:
   extends: .gcc-x86-64-build-debug
   variables:
diff --git a/automation/gitlab-ci/test.yaml b/automation/gitlab-ci/test.yaml
index 6aabdb9d156f..58a90be5ed0e 100644
--- a/automation/gitlab-ci/test.yaml
+++ b/automation/gitlab-ci/test.yaml
@@ -459,3 +459,11 @@ qemu-smoke-ppc64le-powernv9-gcc:
   needs:
     - qemu-system-ppc64-8.1.0-ppc64-export
     - debian-bullseye-gcc-ppc64le-debug
+
+qemu-alpine-x86_64-gcc-livepatch:
+  extends: .qemu-x86-64
+  script:
+    - ./automation/scripts/qemu-alpine-x86_64-livepatch.sh 2>&1 | tee 
${LOGFILE}
+  needs:
+    - *x86-64-test-needs
+    - alpine-3.18-gcc-livepatch
diff --git a/automation/scripts/build-livepatch 
b/automation/scripts/build-livepatch
new file mode 100755
index 000000000000..ac86b17ae5e4
--- /dev/null
+++ b/automation/scripts/build-livepatch
@@ -0,0 +1,27 @@
+#!/bin/bash -ex
+
+# Do a regular build first
+./automation/scripts/build
+
+# Build a test livepatch using livepatch-build-tools.
+
+if [[ "$XEN_TARGET_ARCH" != "x86_64" ]]; then
+    exit 1
+fi
+
+BASE=xen/arch/x86/test/smoc-lp.c
+ALT=xen/arch/x86/test/smoc-lp-alt.c
+
+[[ -f $BASE && -f $ALT ]]
+
+# git diff --no-index returns 0 if no differences, otherwise 1.
+git diff --no-index --output=test.patch $BASE $ALT && exit 1
+
+BUILDID=$(readelf -Wn xen/xen-syms | sed -n -e 's/^.*Build ID: //p')
+
+git clone https://xenbits.xen.org/git-http/livepatch-build-tools.git
+cd livepatch-build-tools
+make
+./livepatch-build -s ../ -p ../test.patch -o out -c ../xen/.config \
+    --depends $BUILDID --xen-depends $BUILDID
+cp out/test.livepatch ../binaries/test.livepatch
diff --git a/automation/scripts/qemu-alpine-x86_64-livepatch.sh 
b/automation/scripts/qemu-alpine-x86_64-livepatch.sh
new file mode 100755
index 000000000000..da478cac4376
--- /dev/null
+++ b/automation/scripts/qemu-alpine-x86_64-livepatch.sh
@@ -0,0 +1,68 @@
+#!/bin/bash
+
+set -ex
+
+cd binaries
+# initrd.tar.gz is Dom0 rootfs
+mkdir -p rootfs
+cd rootfs
+tar xvzf ../initrd.tar.gz
+mkdir proc
+mkdir run
+mkdir srv
+mkdir sys
+rm var/run
+cp -ar ../dist/install/* .
+cp ../test.livepatch ./root/
+cat << "EOF" >> etc/local.d/xen-lp.start
+#!/bin/bash
+
+set -ex
+
+trap poweroff EXIT
+
+export LD_LIBRARY_PATH=/usr/local/lib
+
+xen-livepatch test && exit 1 || true
+
+xen-livepatch load /root/test.livepatch
+
+# Cannot fail now
+xen-livepatch test
+
+xen-livepatch revert test
+xen-livepatch unload test
+
+xen-livepatch test && exit 1 || true
+
+echo "SUCCESS"
+EOF
+chmod +x etc/local.d/xen-lp.start
+echo "rc_verbose=yes" >> etc/rc.conf
+# rebuild Dom0 rootfs
+find . |cpio -H newc -o|gzip > ../xen-rootfs.cpio.gz
+cd ../..
+
+cat >> binaries/pxelinux.0 << EOF
+#!ipxe
+
+kernel xen console=com1 console_timestamps=boot
+module bzImage console=hvc0
+module xen-rootfs.cpio.gz
+boot
+EOF
+
+# Run the test
+rm -f smoke.serial
+timeout -k 1 360 \
+qemu-system-x86_64 \
+    -cpu qemu64,+svm \
+    -m 2G -smp 2 \
+    -monitor none -serial stdio \
+    -nographic \
+    -device virtio-net-pci,netdev=n0 \
+    -netdev user,id=n0,tftp=binaries,bootfile=/pxelinux.0 |& \
+        tee smoke.serial | sed 's/\r//'
+
+grep -q "SUCCESS" smoke.serial
+exit 0
-- 
2.43.0