kernel plugin: properly generate Ubuntu kernel .config (#4210)

Recent Ubuntu kernels (>= Jammy) are now using a new format to store their .config, called annotations [1]. The kernel plugin is trying to assemble a .config using the old config chunks stored in `debian.<kernel>/config/*` that are not available anymore in the kernels that are using this new annotations model. Instead of trying to manually assemble the config we should rely on `debian/rules genconfigs` that is more portable across different Ubuntu kernels and releases. [1] https://lists.ubuntu.com/archives/kernel-team/2023-June/140230.html Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
canonical · Aug 23, 2023 · da90067 · da90067
1 parent 7f8d4cf
commit da90067
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Showing 3 changed files with 33 additions and 24 deletions.
diff --git a/snapcraft_legacy/plugins/v2/_kernel_build.py b/snapcraft_legacy/plugins/v2/_kernel_build.py
@@ -278,17 +278,20 @@ def _do_base_config_cmd(
         logger.info("Using ubuntu config flavour %s", config_flavour)
         conf_cmd = textwrap.dedent(
             """	echo "Assembling Ubuntu config..."
-	branch=$(cut -d'.' -f 2- < ${{KERNEL_SRC}}/debian/debian.env)
-	baseconfigdir=${{KERNEL_SRC}}/debian.${{branch}}/config
-	archconfigdir=${{KERNEL_SRC}}/debian.${{branch}}/config/${{DEB_ARCH}}
-	ubuntuconfig=${{baseconfigdir}}/config.common.ubuntu
-	archconfig=${{archconfigdir}}/config.common.${{DEB_ARCH}}
-	flavourconfig=${{archconfigdir}}/config.flavour.{config_flavour}
-	cat ${{ubuntuconfig}} ${{archconfig}} ${{flavourconfig}} \
-> {dest_dir}/.config 2>/dev/null || true
 	if [ -f ${{KERNEL_SRC}}/debian/rules ] && [ -x ${{KERNEL_SRC}}/debian/rules ]; then
+		# Generate Ubuntu kernel configs
+		pushd ${{KERNEL_SRC}}
+		fakeroot debian/rules clean genconfigs || true
+		popd
+
+		# Pick the right kernel .config for the target arch and flavour
+		ubuntuconfig=${{KERNEL_SRC}}/CONFIGS/${{DEB_ARCH}}-config.flavour.{config_flavour}
+		cat ${{ubuntuconfig}} > {dest_dir}/.config
+
+		# Clean up kernel source directory
 		pushd ${{KERNEL_SRC}}
 		fakeroot debian/rules clean
+		rm -rf CONFIGS/
 		popd
 	fi""".format(
                 config_flavour=config_flavour, dest_dir=dest_dir

diff --git a/tests/legacy/unit/plugins/v2/test_kernel.py b/tests/legacy/unit/plugins/v2/test_kernel.py
@@ -1302,17 +1302,20 @@ def _is_sub_array(array, sub_array):
     "if [ ! -e ${SNAPCRAFT_PART_BUILD}/.config ]; then",
     textwrap.dedent(
         """	echo "Assembling Ubuntu config..."
-	branch=$(cut -d'.' -f 2- < ${KERNEL_SRC}/debian/debian.env)
-	baseconfigdir=${KERNEL_SRC}/debian.${branch}/config
-	archconfigdir=${KERNEL_SRC}/debian.${branch}/config/${DEB_ARCH}
-	ubuntuconfig=${baseconfigdir}/config.common.ubuntu
-	archconfig=${archconfigdir}/config.common.${DEB_ARCH}
-	flavourconfig=${archconfigdir}/config.flavour.raspi
-	cat ${ubuntuconfig} ${archconfig} ${flavourconfig} \
-> ${SNAPCRAFT_PART_BUILD}/.config 2>/dev/null || true
 	if [ -f ${KERNEL_SRC}/debian/rules ] && [ -x ${KERNEL_SRC}/debian/rules ]; then
+		# Generate Ubuntu kernel configs
+		pushd ${KERNEL_SRC}
+		fakeroot debian/rules clean genconfigs || true
+		popd
+
+		# Pick the right kernel .config for the target arch and flavour
+		ubuntuconfig=${KERNEL_SRC}/CONFIGS/${DEB_ARCH}-config.flavour.raspi
+		cat ${ubuntuconfig} > ${SNAPCRAFT_PART_BUILD}/.config
+
+		# Clean up kernel source directory
 		pushd ${KERNEL_SRC}
 		fakeroot debian/rules clean
+		rm -rf CONFIGS/
 		popd
 	fi"""
     ),

diff --git a/tests/unit/parts/plugins/test_kernel.py b/tests/unit/parts/plugins/test_kernel.py
@@ -1401,17 +1401,20 @@ def _is_sub_array(array, sub_array):
     "if [ ! -e ${CRAFT_PART_BUILD}/.config ]; then",
     textwrap.dedent(
         """	echo "Assembling Ubuntu config..."
-	branch=$(cut -d'.' -f 2- < ${KERNEL_SRC}/debian/debian.env)
-	baseconfigdir=${KERNEL_SRC}/debian.${branch}/config
-	archconfigdir=${KERNEL_SRC}/debian.${branch}/config/${DEB_ARCH}
-	ubuntuconfig=${baseconfigdir}/config.common.ubuntu
-	archconfig=${archconfigdir}/config.common.${DEB_ARCH}
-	flavourconfig=${archconfigdir}/config.flavour.raspi
-	cat ${ubuntuconfig} ${archconfig} ${flavourconfig} \
-> ${CRAFT_PART_BUILD}/.config 2>/dev/null || true
 	if [ -f ${KERNEL_SRC}/debian/rules ] && [ -x ${KERNEL_SRC}/debian/rules ]; then
+		# Generate Ubuntu kernel configs
+		pushd ${KERNEL_SRC}
+		fakeroot debian/rules clean genconfigs || true
+		popd
+
+		# Pick the right kernel .config for the target arch and flavour
+		ubuntuconfig=${KERNEL_SRC}/CONFIGS/${DEB_ARCH}-config.flavour.raspi
+		cat ${ubuntuconfig} > ${CRAFT_PART_BUILD}/.config
+
+		# Clean up kernel source directory
 		pushd ${KERNEL_SRC}
 		fakeroot debian/rules clean
+		rm -rf CONFIGS/
 		popd
 	fi"""
     ),