diff options
authorMike Crowe <>2021-10-07 14:17:57 +0100
committerRichard Purdie <>2021-12-09 13:49:47 +0000
commit10a4a132e87e835726bf5da81a60f6f509b90765 (patch)
parent4bacb37e9fd55d8bf8ead8d6879e95b31e1dfb55 (diff)
kernel: improve transformation from KERNEL_IMAGETYPE_FOR_MAKE
In 526bdd88ccd758204452579333ba188e29270bde the imageType loop in kernel_do_deploy was changed to use KERNEL_IMAGETYPE_FOR_MAKE rather than KERNEL_IMAGETYPES. This broke the special handling for fitImage immediately below because KERNEL_IMAGETYPE_FOR_MAKE never contains fitImage. It has always been my understanding that KERNEL_IMAGETYPE_FOR_MAKE controlled what was passed to make, but KERNEL_IMAGETYPE controlled what was installed/deployed. When the two are different then it's the responsibility of whoever set KERNEL_IMAGETYPE_FOR_MAKE to ensure that whatever comes out of the kernel build system has been transformed in to the requested form by the time of installation. This is what happens for kernel.bbclass's own support for vmlinux.gz. I think this means that for KERNEL_IMAGETYPE vmlinux.gz, kernel.bbclass is responsible for generating vmlinux.gz.initramfs[1] so that kernel_do_deploy can deploy it. This means that the change in 526bdd88ccd758204452579333ba188e29270bde can be reverted, fixing KERNEL_IMAGETYPE = "fitImage". In addition, it ought to be possible for recipes and other classes that use kernel.bbclass to hook into this mechanism by setting KERNEL_IMAGETYPE_FOR_MAKE and performing their own transformations. do_bundle_initramfs calls kernel_do_compile and we don't want it to transform vmlinux to vmlinux.gz at that point, since it will fight against the careful renaming and preserving that do_bundle_initramfs does. Let's separate the transformation out of kernel_do_compile to a new do_transform_kernel task that can be run at the right time. This means that it's also logical to perform the equivalent translation for the kernel with the initramfs in a separate do_transform_bundled_initramfs task too. This leaves two clear customisation points for recipes and other classes to hook into the process and perform their transformations: do_transform_kernel and do_transform_bundled_initramfs. (I care about this because our recipes that use kernel.bbclass also set KERNEL_IMAGETYPE_FOR_MAKE and transform vmlinux into a form suitable for our bootloader after do_compile and do_bundle_initramfs into the format matching KERNEL_IMAGETYPE. I'm unable to successfully bundle an initramfs after 526bdd88ccd758204452579333ba188e29270bde, but I didn't want to just revert that change to reintroduce the bug that it was fixing.) I can't say that I'm entirely happy with this change, but I'm unsure what to do to improve it. I find the way that both the bare kernel and the one with the initramfs both get deployed to be confusing, and a waste of build time. I would like to not actually generate a publishable kernel image at all during do_compile when an initramfs is in use, but I suspect that this would affect valid use cases that I'm not aware of. Signed-off-by: Mike Crowe <> [1] It could be argued that this should be vmlinux.initramfs.gz, but that would require another special case in kernel_do_deploy and the filename is only visible within this class and the recipes that use it anyway. Signed-off-by: Alexandre Belloni <>
1 files changed, 18 insertions, 3 deletions
diff --git a/meta/classes/kernel.bbclass b/meta/classes/kernel.bbclass
index 2d219cb5e5..0df24ac910 100644
--- a/meta/classes/kernel.bbclass
+++ b/meta/classes/kernel.bbclass
@@ -77,7 +77,7 @@ python __anonymous () {
# KERNEL_IMAGETYPES may contain a mixture of image types supported directly
# by the kernel build system and types which are created by post-processing
# the output of the kernel build system (e.g. compressing vmlinux ->
- # vmlinux.gz in kernel_do_compile()).
+ # vmlinux.gz in kernel_do_transform_kernel()).
# KERNEL_IMAGETYPE_FOR_MAKE should contain only image types supported
# directly by the kernel build system.
@@ -134,6 +134,8 @@ set -e
# standalone for use by wic and other tools.
if image:
d.appendVarFlag('do_bundle_initramfs', 'depends', ' ${INITRAMFS_IMAGE}:do_image_complete')
+ if image and bb.utils.to_boolean(d.getVar('INITRAMFS_IMAGE_BUNDLE')):
+'do_transform_bundled_initramfs', 'do_deploy', 'do_bundle_initramfs', d)
# NOTE: setting INITRAMFS_TASK is for backward compatibility
# The preferred method is to set INITRAMFS_IMAGE, because
@@ -316,6 +318,14 @@ do_bundle_initramfs () {
do_bundle_initramfs[dirs] = "${B}"
+kernel_do_transform_bundled_initramfs() {
+ # vmlinux.gz is not built by kernel
+ if (echo "${KERNEL_IMAGETYPES}" | grep -wq "vmlinux\.gz"); then
+ gzip -9cn < ${KERNEL_OUTPUT_DIR}/vmlinux.initramfs > ${KERNEL_OUTPUT_DIR}/vmlinux.gz.initramfs
+ fi
+do_transform_bundled_initramfs[dirs] = "${B}"
python do_devshell:prepend () {
os.environ["LDFLAGS"] = ''
@@ -364,12 +374,17 @@ kernel_do_compile() {
for typeformake in ${KERNEL_IMAGETYPE_FOR_MAKE} ; do
oe_runmake ${typeformake} CC="${KERNEL_CC}" LD="${KERNEL_LD}" ${KERNEL_EXTRA_ARGS} $use_alternate_initrd
+kernel_do_transform_kernel() {
# vmlinux.gz is not built by kernel
if (echo "${KERNEL_IMAGETYPES}" | grep -wq "vmlinux\.gz"); then
mkdir -p "${KERNEL_OUTPUT_DIR}"
gzip -9cn < ${B}/vmlinux > "${KERNEL_OUTPUT_DIR}/vmlinux.gz"
+do_transform_kernel[dirs] = "${B}"
+addtask transform_kernel after do_compile before do_install
do_compile_kernelmodules() {
@@ -621,7 +636,7 @@ inherit cml1
-EXPORT_FUNCTIONS do_compile do_install do_configure
+EXPORT_FUNCTIONS do_compile do_transform_kernel do_transform_bundled_initramfs do_install do_configure
# kernel-base becomes kernel-${KERNEL_VERSION}
# kernel-image becomes kernel-image-${KERNEL_VERSION}
@@ -772,7 +787,7 @@ kernel_do_deploy() {
if [ ! -z "${INITRAMFS_IMAGE}" -a x"${INITRAMFS_IMAGE_BUNDLE}" = x1 ]; then
- for imageType in ${KERNEL_IMAGETYPE_FOR_MAKE} ; do
+ for imageType in ${KERNEL_IMAGETYPES} ; do
if [ "$imageType" = "fitImage" ] ; then