Re: [PATCH 7/7] linux-custom: rewrite to no longer depend on the kernel's builddeb

[Jan Kiszka <jan.kiszka@siemens.com>]

On 05.11.19 17:22, Jan Kiszka wrote:
> On 05.11.19 16:26, [ext] Jan Kiszka wrote:
>> On 05.11.19 14:57, Cedric Hombourger wrote:
>>> Regain control over the packaging of the Linux kernel by providing our
>>> own debian recipes (debian,{control,rules} files and friends) instead
>>> of using the kernel's builddeb script. This will allow generation of
>>> packages for "perf" (not included in this changeset) with per distro
>>> scheme (Debian and Ubuntu have differences) and maintain compatibility
>>> with upstream packages generated from different source packages but
>>> dependent on a certain deployment scheme (e.g. linux-base for Debian)
>>>
>>> Signed-off-by: Cedric Hombourger <Cedric_Hombourger@mentor.com>
>>> ---
>>>  doc/custom_kernel.md                          | 181 ++++++++++++++++
>>>  .../linux/files/build-kernel.sh               | 128 ------------
>>>  meta/recipes-kernel/linux/files/debian/compat |   1 +
>>>  .../linux/files/debian/control.tmpl           |  36 ++++
>>>  meta/recipes-kernel/linux/files/debian/files  |   5 +
>>>  .../linux/files/debian/isar/build.tmpl        |  36 ++++
>>>  .../linux/files/debian/isar/clean.tmpl        |  20 ++
>>>  .../linux/files/debian/isar/common.tmpl       |  60 ++++++
>>>  .../linux/files/debian/isar/install.tmpl      | 197 ++++++++++++++++++
>>>  .../files/debian/linux-image.postinst.tmpl    |  22 ++
>>>  .../files/debian/linux-image.postrm.tmpl      |  18 ++
>>>  .../linux/files/debian/rules.tmpl             |  39 ++++
>>>  meta/recipes-kernel/linux/linux-custom.inc    | 172 ++++++++++-----
>>>  13 files changed, 732 insertions(+), 183 deletions(-)
>>>  create mode 100644 doc/custom_kernel.md
>>>  delete mode 100644 meta/recipes-kernel/linux/files/build-kernel.sh
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/compat
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/control.tmpl
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/files
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/isar/build.tmpl
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/isar/clean.tmpl
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/isar/common.tmpl
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/isar/install.tmpl
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/linux-image.postinst.tmpl
>>>  create mode 100644 meta/recipes-kernel/linux/files/debian/linux-image.postrm.tmpl
>>>  create mode 100755 meta/recipes-kernel/linux/files/debian/rules.tmpl
>>>
>>> diff --git a/doc/custom_kernel.md b/doc/custom_kernel.md
>>> new file mode 100644
>>> index 0000000..5ab2599
>>> --- /dev/null
>>> +++ b/doc/custom_kernel.md
>>> @@ -0,0 +1,181 @@
>>> +# Custom kernel recipe for Isar
>>> +
>>> +## Contents
>>> +
>>> + - [Summary](#summary)
>>> + - [Proposal owners](#proposal-owners)
>>> + - [Current status](#current-status)
>>> + - [Detailed description](#detailed-description)
>>> + - [Benefit to Isar](#benefit-to-isar)
>>> + - [How can I help?](#how-can-i-help)
>>> + - [Scope](#scope)
>>> + - [How to test](#how-to-test)
>>> + - [Dependencies](#dependencies)
>>> + - [Documentation](#documentation)
>>> + - [Questions and answers](#questions-and-answers)
>>> +
>>> +## Summary
>>> +
>>> +Isar currently uses the Linux kernel's builddeb script to generate linux-image,
>>> +linux-headers and linux-libc-dev packages for your custom kernel sources. The
>>> +main benefit of this approach was that the low level details of how to package
>>> +the Linux kernel image, modules and headers were left in the kernel. There are
>>> +however some drawbacks: Isar had to repack generated packages to introduce some
>>> +of the changes it needs such as suffixing the kernel packages with the name of
>>> +the custom kernel (e.g. with "mainline" for the "linux-mainline" recipe), lack
>>> +of automatic dependencies (the builddeb script from the kernel does not use
>>> +debhelper), it was difficult to add packages especially distribution specific
>>> +packages (maintain version specific patch in Isar vs being able to upstream
>>> +distribution specific changes upstream), etc. This change is about being less
>>> +dependent on the kernel packaging scripts (which aren't used by major distros
>>> +anyway) and regain control on how we want or need the Linux kernel packaged.
>>> +
>>> +## Proposal owners
>>> +
>>> + * name: [Cedric Hombourger](https://github.com/chombourger)
>>> +
>>> +## Current status
>>> +
>>> +### Tests
>>> +
>>> +The following were recently checked:
>>> +
>>> + * Custom kernels in meta-isar build without (known) failures
>>> + * initrd image gets generated when the kernel is added to the rootfs
>>> + * `ISAR_CROSS_COMPILE` is supported
>>> + * `KERNEL_FILE` is honored
>>> + * `KERNEL_DEFCONFIG` may either be a file (specified via `SRC_URI`) or a
>>> +   kernel-provided defconfig
>>> + * Config fragments get merged with the user-specified kernel configuration
>>> + * Path to installed DTBs may be configured (new)
>>> + * Configuration and build from a `devshell`
>>> + * Support for the `KERNEL_LIBC_DEV_DEPLOY` directive
>>> +
>>> +while the following needs work:
>>> +
>>> + * Check if custom-kernel builds are reproducible
>>> +
>>> +### Remaining work items
>>> +
>>> + * Check if there is a better way to cross compile kernel "scripts" such as
>>> +   `fixdep` or `modpost` than manually compiling them (they are compiled for
>>> +   the build machine (amd64) and not for the target (e.g. armhf) even though
>>> +   we are cross-compiling - yet the linux-headers package should be shipping
>>> +   "scripts" for the target machine)
>>> +
>>> +## Detailed description
>>> +
>>> +### Requirements
>>> +
>>> +#### Current
>>> +
>>> +Isar has had a `linux-custom` recipe for a long time and counts many users. It is therefore
>>> +paramount to maintain features that it has today with no or little changes to the APIs. The
>>> +following requirements were identified and will be maintained:
>>> +
>>> + 1. Sources to the custom Linux kernel may be specified via `SRC_URI`
>>> +
>>> + 2. Configure the kernel via an in-tree or an external `defconfig`
>>
>> Reference to KERNEL_DEFCONFIG is missing.
>>
>>> +
>>> + 3. Support kernel configuration tweaks via configuration fragments (`.cfg` files)
>>> +
>>> + 4. Patches to the linux kernel may be specified via `SRC_URI`
>>> +
>>> + 5. Ensure that the Isar recipe `PV` matches the kernel release identifier (`KERNEL_RELEASE`)
>>> +
>>> + 6. Produce a `linux-image` package that ships the kernel image and modules
>>> +
>>> + 7. Allow the name of the kernel image to be changed via `KERNEL_FILE` (defaults to `vmlinuz`)
>>> +
>>> + 8. Produce a `linux-headers` package which includes kernel headers and kbuild scripts/tools
>>> +
>>> + 9. The `linux-headers` package shall support native and cross compiles of out-of-tree kernel modules
>>
>> One package to serve them all? Is that the use case for patch 6? IOW, we
>> are now building linux-headers for the target, not the host OS anymore?
>> What's the slowdown compare to cross-linux-headers?
>>
>> The current policy is that, when cross-building, our -dev packagages
>> (which is what linux-headers falls under) will work natively with the
>> buildchroot. The future path is clearly generating fitting packages for
>> both host and target. Or is there anything in the linux-headers that
>> prevents providing both?
>>
>>> +
>>> + 10. Produce a `linux-libc-dev` package to support user-land builds
>>
>> This should be opt-in only: No need to build it when we don't ship it.
>> Just add the related fragement to debian/control when
>> KERNEL_LIBC_DEV_DEPLOY is set.
>>
>>> +
>>> + 11. Only ship the `linux-libc-dev` package if instructed to (`KERNEL_LIBC_DEV_DEPLOY` equals to `"1"`)
>>> +
>>> + 12. Support both native and cross compiles (`ISAR_CROSS_COMPILE`)
>>> +
>>> + 13. Support for the following kernel architectures:
>>> +
>>> +   * arm
>>> +   * arm64
>>> +   * mips
>>> +   * x86
>>> +
>>> + 14. Support `devshell` (kernel configuration shall be applied)
>>> +
>>> +#### New requirements (proposed)
>>> +
>>> +This proposal includes the following new requirements:
>>> +
>>> + 1. Support creation of additional packages
>>> +
>>> + 2. Allow per-distro packaging tweaks
>>> +
>>> +### Approach
>>> +
>>> +The new implementation will have the `builddeb` code ported from the Linux kernel included to the
>>> +Isar environment. It will be refactor to support pre and post hooks. Hooks may be used by external
>>> +layers to extend the kernel packaging instructions provided by "stock" Isar or by Isar itself to
>>> +implement distro-specific packages or tweaks.
>>> +
>>> +Hooks need the ability to add `build` and `install` steps which can be achieved by having the main
>>> +`build` and `install` steps call pre and post scripts. This will however solve only one side of the
>>> +problem: new packages should be declared in the `debian/control` file. The packaging process
>>> +(initiated by `debian/rules`) will use a baseline `control` file when started and a mechanism will
>>> +be provided for hooks to append `control` blocks as they are processed.
>>
>> Is this a section addressing users or reviewers? The latter audience is
>> better addressed via the commit log.
>>
>>> +
>>> +### Future work
>>> +
>>> +In the event where this proposal is accepted, here are a few future projects that are being
>>> +considered:
>>> +
>>> + 1. Package `perf` as Debian does
>>> +
>>> + 2. Add `ubuntu` as an Isar supported target distro and validate `linux-custom` recipe
>>> + 
>>> +## Benefit to Isar
>>> +
>>> + * Control the kernel build and packaging process
>>> +
>>> + * No longer need to repack packages
>>> +
>>> + * Provide hooks for custom kernel recipes to add build/install directives
>>
>> Careful with hooks! They tend to pile up mess. Where exactly do you want
>> them? What for?
>>
>>> +
>>> +## How can I help?
>>> +
>>> + * Check if you are able to build your own linux-custom recipes with this change
>>> + * Check if packages generated by this recipe are compatible with your Debian-based distro
>>> + * Review and provide comments on this changeset
>>> + * Create templates for distro-specific packages (e.g. perf)
>>> +
>>> +## Scope
>>> +
>>> + * Proposal owners: proposal owners are to communicate the idea to isar-users and make sure
>>> +   that all of their requirements are met (to the extent they are already supported with the
>>> +   current solution) or may be met in the future.
>>> +
>>> + * Other developers: port your out-of-tree linux-custom recipes to this new solution and
>>> +   report issues.
>>> +
>>> +## How to test?
>>> +
>>> +The linux-mainline recipe may be used for some basic testing. This recipe is being used by the
>>> +following machines:
>>> +
>>> + * de0-nano-soc
>>> + * qemumipsel
>>> +
>>> +## Dependencies
>>> +
>>> + * None
>>> +
>>> +## Documentation
>>> +
>>> + * Document user-visible variables added by this proposal
>>> +
>>> +## Questions and answers
>>> +
>>> + * None
>>> diff --git a/meta/recipes-kernel/linux/files/build-kernel.sh b/meta/recipes-kernel/linux/files/build-kernel.sh
>>> deleted file mode 100644
>>> index f56e96c..0000000
>>> --- a/meta/recipes-kernel/linux/files/build-kernel.sh
>>> +++ /dev/null
>>> @@ -1,128 +0,0 @@
>>> -#!/bin/bash
>>> -#
>>> -# Custom kernel build
>>> -#
>>> -# This software is a part of ISAR.
>>> -# Copyright (c) Siemens AG, 2018
>>> -#
>>> -# SPDX-License-Identifier: MIT
>>> -
>>> -source /isar/common.sh
>>> -
>>> -host_arch=$(dpkg --print-architecture)
>>> -
>>> -if [ "$host_arch" != "$target_arch" ]; then
>>> -    case $target_arch in
>>> -    armhf)
>>> -        export ARCH=arm
>>> -        export CROSS_COMPILE="arm-linux-gnueabihf-"
>>> -        ;;
>>> -    arm64)
>>> -        export ARCH=arm64
>>> -        export CROSS_COMPILE="aarch64-linux-gnu-"
>>> -        ;;
>>> -    mipsel)
>>> -        export ARCH=mips
>>> -        export CROSS_COMPILE="mipsel-linux-gnu-"
>>> -        ;;
>>> -    *)
>>> -        echo "error: unsupported architecture ($target_arch)"
>>> -        exit 1
>>> -        ;;
>>> -    esac
>>> -fi
>>> -
>>> -REPACK_DIR="$1/../repack"
>>> -REPACK_LINUX_IMAGE_DIR="${REPACK_DIR}/linux-image"
>>> -REPACK_LINUX_HEADERS_DIR="${REPACK_DIR}/linux-headers"
>>> -
>>> -make ${KERNEL_CONFIG_TARGET} || exit ${?}
>>> -if [ -n "${KERNEL_FRAGMENTS}" ]; then
>>> -    scripts/kconfig/merge_config.sh -m .config ${KERNEL_FRAGMENTS}
>>> -fi
>>> -
>>> -KV=$( make -s kernelrelease )
>>> -if [ "${KV}" != "${PV}" ]; then
>>> -	echo "ERROR: Recipe PV is \"${PV}\" but should be \"${KV}\"" 1>&2
>>> -	echo "ERROR: Probably due to CONFIG_LOCALVERSION" 1>&2
>>> -	exit 1
>>> -fi
>>> -
>>> -rm -f .version
>>> -KBUILD_DEBARCH=$target_arch make -j $(($(nproc) * 2)) deb-pkg
>>> -
>>> -rm -rf "${REPACK_DIR}"
>>> -mkdir -p "${REPACK_DIR}"
>>> -mkdir -p "${REPACK_LINUX_IMAGE_DIR}"
>>> -mkdir -p "${REPACK_LINUX_HEADERS_DIR}"
>>> -
>>> -cp -a debian "${REPACK_DIR}"
>>> -
>>> -# dpkg-gencontrol performs cross-incompatible checks on the
>>> -# Architecture field; trick it to accept the control file
>>> -sed -i "s/Architecture: .*/Architecture: any/" "${REPACK_DIR}/debian/control"
>>> -
>>> -cd ..
>>> -
>>> -dpkg-deb -R linux-image-${PV}_${PV}-1_*.deb "${REPACK_LINUX_IMAGE_DIR}"
>>> -dpkg-deb -R linux-headers-${PV}_${PV}-1_*.deb "${REPACK_LINUX_HEADERS_DIR}"
>>> -
>>> -dpkg-gencontrol -crepack/debian/control \
>>> -	-lrepack/debian/changelog \
>>> -	-frepack/debian/files \
>>> -	-plinux-image-${PV} \
>>> -	-P"${REPACK_LINUX_IMAGE_DIR}" \
>>> -	-DPackage="linux-image-${KERNEL_NAME}" \
>>> -	-DSection=kernel \
>>> -	-DPriority=required \
>>> -	-DDepends="${KERNEL_DEBIAN_DEPENDS}" \
>>> -	-DArchitecture=$target_arch
>>> -
>>> -# Add Debian-like link installation to postinst
>>> -mkdir -p ${REPACK_LINUX_IMAGE_DIR}/lib/modules/${PV}
>>> -touch "${REPACK_LINUX_IMAGE_DIR}/lib/modules/${PV}/.fresh-install"
>>> -sed -i "${REPACK_LINUX_IMAGE_DIR}/DEBIAN/postinst" \
>>> -    -e "/^set -e$/a\\
>>> -\\
>>> -if [ -f /lib/modules/${PV}/.fresh-install ]; then\\
>>> -	change=install\\
>>> -else\\
>>> -	change=upgrade\\
>>> -fi\\
>>> -linux-update-symlinks \$change ${PV} /boot/${KERNEL_FILE}-${PV}\\
>>> -rm -f /lib/modules/${PV}/.fresh-install"
>>> -
>>> -# Add Debian-like link removal to postrm
>>> -sed -i "${REPACK_LINUX_IMAGE_DIR}/DEBIAN/postrm" \
>>> -    -e "/^set -e$/a\\
>>> -\\
>>> -rm -f /lib/modules/${PV}/.fresh-install\\
>>> -\\
>>> -if [ \"\$1\" != upgrade ] && command -v linux-update-symlinks >/dev/null; then\\
>>> -	linux-update-symlinks remove ${PV}  /boot/${KERNEL_FILE}-${PV}\\
>>> -fi"
>>> -
>>> -# Make sure arm64 kernels are decompressed
>>> -if [ "$target_arch" = "arm64" ]; then
>>> -	kernel_file="${REPACK_LINUX_IMAGE_DIR}/boot/${KERNEL_FILE}-${PV}"
>>> -	mv "${kernel_file}" "${kernel_file}.gz"
>>> -	gunzip "${kernel_file}.gz"
>>> -fi
>>> -
>>> -dpkg-gencontrol -crepack/debian/control \
>>> -	-lrepack/debian/changelog \
>>> -	-frepack/debian/files \
>>> -	-plinux-headers-${PV} \
>>> -	-P"${REPACK_LINUX_HEADERS_DIR}" \
>>> -	-Vkernel:debarch="${KERNEL_NAME}" \
>>> -	-DPackage="linux-headers-${KERNEL_NAME}" \
>>> -	-DSection=kernel \
>>> -	-DDepends="${KERNEL_HEADERS_DEBIAN_DEPENDS}" \
>>> -	-DArchitecture=$target_arch
>>> -
>>> -fakeroot dpkg-deb -b "${REPACK_LINUX_IMAGE_DIR}" \
>>> -	linux-image-${KERNEL_NAME}_${PV}-1_${KERNEL_NAME}.deb
>>> -rm -f linux-image-${PV}_${PV}-1_*.deb
>>> -fakeroot dpkg-deb -b "${REPACK_LINUX_HEADERS_DIR}" \
>>> -	linux-headers-${KERNEL_NAME}_${PV}-1_${KERNEL_NAME}.deb
>>> -rm -f linux-headers-${PV}_${PV}-1_*.deb
>>> diff --git a/meta/recipes-kernel/linux/files/debian/compat b/meta/recipes-kernel/linux/files/debian/compat
>>> new file mode 100644
>>> index 0000000..ec63514
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/compat
>>> @@ -0,0 +1 @@
>>> +9
>>> diff --git a/meta/recipes-kernel/linux/files/debian/control.tmpl b/meta/recipes-kernel/linux/files/debian/control.tmpl
>>> new file mode 100644
>>> index 0000000..1295466
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/control.tmpl
>>> @@ -0,0 +1,36 @@
>>> +Source: linux-${KERNEL_NAME_PROVIDED}
>>> +Section: kernel
>>> +Priority: optional
>>> +Maintainer: ${MAINTAINER}
>>> +Build-Depends: bc, kmod, cpio, ${KBUILD_DEPENDS}
>>> +Homepage: http://www.kernel.org/
>>
>> Standard-Version?
>>
>>> +
>>> +Package: linux-image-${KERNEL_NAME_PROVIDED}
>>> +Architecture: any
>>> +Depends: ${KERNEL_DEBIAN_DEPENDS}
>>> +Description: ${KERNEL_NAME_PROVIDED} Linux kernel, version ${PV}
>>> + This package contains the Linux kernel, modules and corresponding other
>>> + files, version: ${PV}.
>>> +
>>> +Package: linux-headers-${KERNEL_NAME_PROVIDED}
>>> +Architecture: any
>>> +Depends: ${KERNEL_HEADERS_DEBIAN_DEPENDS}, ${perl:Depends}, ${shlib:Depends}
>>> +Description: ${KERNEL_NAME_PROVIDED} Linux kernel headers for ${PV}
>>> + This package provides kernel header files for ${PV} on ${DISTRO_ARCH}
>>> + .
>>> + This is useful for people who need to build external modules
>>> +
>>> +Package: linux-libc-dev
>>
>> See above, should not be here by default.
>>
>>> +Section: devel
>>> +Provides: linux-kernel-headers
>>> +Architecture: any
>>> +Description: Linux support headers for userspace development
>>> + This package provides userspaces headers from the Linux kernel.  These headers
>>> + are used by the installed headers for GNU glibc and other system libraries.
>>> +
>>> +Package: linux-image-${KERNEL_NAME_PROVIDED}-dbg
>>> +Section: debug
>>> +Architecture: any
>>> +Description: Linux kernel debugging symbols for ${PV}
>>> + This package will come in handy if you need to debug the kernel. It provides
>>> + all the necessary debug symbols for the kernel and its modules.
>>> diff --git a/meta/recipes-kernel/linux/files/debian/files b/meta/recipes-kernel/linux/files/debian/files
>>> new file mode 100644
>>> index 0000000..a8ace32
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/files
>>> @@ -0,0 +1,5 @@
>>> +linux-headers_4.19.80-1_mipsel.deb kernel optional
>>> +linux-image-dbg_4.19.80-1_mipsel.deb debug optional
>>> +linux-image_4.19.80-1_mipsel.deb kernel optional
>>> +linux-libc-dev_4.19.80-1_mipsel.deb devel optional
>>> +linux_4.19.80-1_mipsel.buildinfo kernel optional
>>
>> Looks like an accidentally added file.
>>
>>> diff --git a/meta/recipes-kernel/linux/files/debian/isar/build.tmpl b/meta/recipes-kernel/linux/files/debian/isar/build.tmpl
>>> new file mode 100644
>>> index 0000000..ce79d56
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/isar/build.tmpl
>>> @@ -0,0 +1,36 @@
>>> +#!/bin/sh
>>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>>> +# SPDX-License-Identifier: MIT
>>> +
>>> +# Load common stuff
>>> +. ${S}/debian/isar/common || exit ${?}
>>> +
>>> +do_build() {
>>> +
>>> +    # Print a few things that are of particular interest
>>> +    print_settings
>>> +
>>> +    # Trace what we do here
>>> +    set -x
>>> +
>>> +    # Process existing kernel configuration to make sure it is complete
>>> +    # (use defaults for options that were not specified)
>>> +    ${MAKE} O=${KERNEL_BUILD_DIR} olddefconfig || exit ${?}
>>> +
>>> +    # Build the Linux kernel
>>> +    ${MAKE} O=${KERNEL_BUILD_DIR} -j $(nproc) || exit ${?}
>>> +
>>> +    # Stop tracing
>>> +    set +x
>>> +}
>>> +
>>> +print_settings() {
>>> +    cat <<EOF
>>> +# Build settings:
>>> +# ---------------
>>> +# ARCH=${ARCH}
>>> +# CROSS_COMPILE=${CROSS_COMPILE}
>>> +EOF
>>> +}
>>> +
>>> +main build ${*}
>>> diff --git a/meta/recipes-kernel/linux/files/debian/isar/clean.tmpl b/meta/recipes-kernel/linux/files/debian/isar/clean.tmpl
>>> new file mode 100644
>>> index 0000000..2aa3742
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/isar/clean.tmpl
>>> @@ -0,0 +1,20 @@
>>> +#!/bin/sh
>>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>>> +# SPDX-License-Identifier: MIT
>>> +
>>> +# Load common stuff
>>> +. ${S}/debian/isar/common || exit ${?}
>>> +
>>> +do_clean() {
>>> +
>>> +    # Trace what we do here
>>> +    set -x
>>> +
>>> +    rm -rf ${deb_img_dir} ${deb_dbg_dir}
>>> +    rm -rf ${deb_kern_hdrdir} ${deb_libc_hdr_dir}
>>
>> I suppose we rather (or also?) want "make clean" here for the build
>> artifacts. Just make sure to save/restore the debian folder across that
>> step.
>>
>>> +
>>> +    # Stop tracing
>>> +    set +x
>>> +}
>>> +
>>> +main clean ${*}
>>> diff --git a/meta/recipes-kernel/linux/files/debian/isar/common.tmpl b/meta/recipes-kernel/linux/files/debian/isar/common.tmpl
>>> new file mode 100644
>>> index 0000000..b392b46
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/isar/common.tmpl
>>> @@ -0,0 +1,60 @@
>>> +#!/bin/sh
>>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>>> +# SPDX-License-Identifier: MIT
>>> +
>>> +# Isar settings
>>> +ARCH=${KERNEL_ARCH}
>>> +KERNEL_PKG_IMAGE=linux-image-${KERNEL_NAME_PROVIDED}
>>> +KERNEL_PKG_KERN_HEADERS=linux-headers-${KERNEL_NAME_PROVIDED}
>>> +KERNEL_PKG_LIBC_HEADERS=linux-libc-dev
>>> +
>>> +# Constants
>>> +KCONF=.config
>>> +
>>> +# Target directories
>>> +deb_top_dir=${S}/debian
>>> +deb_img_dir=${deb_top_dir}/${KERNEL_PKG_IMAGE}
>>> +deb_dbg_dir=${deb_img_dir}-dbg
>>> +deb_dtb_dir=${deb_img_dir}/${KERNEL_DTB_DIR}
>>> +deb_kern_hdr_dir=${deb_top_dir}/${KERNEL_PKG_KERN_HEADERS}
>>> +deb_libc_hdr_dir=${deb_top_dir}/${KERNEL_PKG_LIBC_HEADERS}
>>> +
>>> +main() {
>>> +    target=${1}
>>> +
>>> +    if [ ! -f ${S}/debian/isar/${target} ]; then
>>> +        echo "error: ${target} is not a supported build target!" >&2
>>> +        return 1
>>> +    fi
>>> +
>>> +    # check for scripts to be sourced
>>> +    for f in ${S}/debian/isar/defaults.d/${target}/*; do
>>> +        [ -f ${f} ] || continue
>>> +        . ${f} || return ${?}
>>> +    done
>>> +
>>> +    # variables to be exported
>>> +    export ARCH
>>> +
>>> +    # are we cross-compiling?
>>> +    BUILD_ARCH=$(dpkg-architecture -qDEB_BUILD_ARCH)
>>> +    if [ "${BUILD_ARCH}" = "${DISTRO_ARCH}" ]; then
>>> +        # no, make sure CROSS_COMPILE isn't set
>>> +        unset CROSS_COMPILE
>>> +    fi
>>> +
>>> +    # check for pre-target scripts
>>> +    for f in ${S}/debian/isar/pre.d/${target}/*; do
>>> +        [ -f ${f} ] || continue
>>> +        sh ${f} || return ${?}
>>> +    done
>>> +
>>> +    # call the actual target script
>>> +    do_${target} || return ${?}
>>> +
>>> +    # check for post-target scripts
>>> +    for f in ${S}/debian/isar/post.d/${target}/*; do
>>> +        [ -f ${f} ] || continue
>>> +        sh ${f} || return ${?}
>>> +    done
>>> +}
>>> diff --git a/meta/recipes-kernel/linux/files/debian/isar/install.tmpl b/meta/recipes-kernel/linux/files/debian/isar/install.tmpl
>>> new file mode 100644
>>> index 0000000..2055669
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/isar/install.tmpl
>>> @@ -0,0 +1,197 @@
>>> +#!/bin/sh
>>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>>> +# SPDX-License-Identifier: MIT
>>> +
>>> +# Load common stuff
>>> +. ${S}/debian/isar/common || exit ${?}
>>> +
>>> +do_install() {
>>> +
>>> +    # check if our kernel was configured
>>> +    if [ ! -f "${O}/.config" ]; then
>>> +        echo "error: kernel not configured!" >&2
>>> +        return 1
>>> +    fi
>>> +
>>> +    # load its configuration
>>> +    . ${O}/.config
>>> +
>>> +    kimage="$(${MAKE} O=${O} -s --no-print-directory image_name)"
>>> +    case "${ARCH}" in
>>> +        mips|powerpc) kimage_path="boot/vmlinux-${PV}"    ;;
>>> +                  um) kimage_path="usr/bin/vmlinux-${PV}" ;;
>>> +                   *) kimage_path="boot/vmlinuz-${PV}"    ;;
>>> +    esac
>>> +
>>> +    print_settings
>>> +
>>> +    # Stop on error
>>> +    set -e
>>> +
>>> +    # Trace what we do here
>>> +    set -x
>>> +
>>> +    install_image
>>> +    install_hooks
>>> +    install_dtbs
>>> +    install_kmods
>>> +    install_headers
>>> +
>>> +    # Stop tracing
>>> +    set +x
>>> +}
>>> +
>>> +print_settings() {
>>> +    cat <<EOF
>>> +Install settings:
>>> +-----------------
>>> +deb_dtb_dir=${deb_dtb_dir}
>>> +deb_hdr_dir=${deb_hdr_dir}
>>> +kimage=${kimage}
>>> +kimage_path=${kimage_path}
>>> +
>>> +EOF
>>> +}
>>> +
>>> +install_image() {
>>> +    install -m 755 -d ${deb_img_dir}/$(dirname ${kimage_path})
>>> +    cp ${O}/${kimage} ${deb_img_dir}/${kimage_path}
>>> +    install_image_debug
>>> +}
>>> +
>>> +install_image_debug() {
>>> +    # Different tools want the image in different locations
>>> +    # perf
>>> +    mkdir -p ${deb_dbg_dir}/usr/lib/debug/lib/modules/${PV}/
>>> +    cp vmlinux ${deb_dbg_dir}/usr/lib/debug/lib/modules/${PV}/
>>> +    # systemtap
>>> +    mkdir -p ${deb_dbg_dir}/usr/lib/debug/boot/
>>> +    ln -s ../lib/modules/$version/vmlinux ${deb_dbg_dir}/usr/lib/debug/boot/vmlinux-${PV}
>>> +    # kdump-tools
>>> +    ln -s lib/modules/${PV}/vmlinux ${deb_dbg_dir}/usr/lib/debug/vmlinux-${PV}
>>> +}
>>> +
>>> +install_hooks() {
>>> +    install -m 755 -d ${deb_img_dir}/etc/kernel/install.d
>>> +    install -m 755 -d ${deb_img_dir}/etc/kernel/postinst.d
>>> +    install -m 755 -d ${deb_img_dir}/etc/kernel/postrm.d
>>> +    install -m 755 -d ${deb_img_dir}/etc/kernel/prerm.d
>>> +}
>>> +
>>> +install_dtbs() {
>>> +    [ -n "${CONFIG_OF}" ] || return 0
>>> +    ${MAKE} O=${O} INSTALL_DTBS_PATH=${deb_dtb_dir} dtbs_install
>>> +}
>>> +
>>> +install_kmods() {
>>> +    [ -n "${CONFIG_MODULES}" ] || return 0
>>> +    ${MAKE} O=${O} INSTALL_MOD_PATH=${deb_img_dir} modules_install
>>> +    touch ${deb_img_dir}/lib/modules/${PV}/.fresh-install
>>> +    rm -fv ${deb_img_dir}/lib/modules/${PV}/build
>>> +    rm -fv ${deb_img_dir}/lib/modules/${PV}/source
>>> +    install_kmods_debug
>>> +}
>>> +
>>> +kmods_sign() {
>>> +    [ -n "${CONFIG_MODULE_SIG_ALL}" ] || return 0
>>> +    ${MAKE} O=${O} INSTALL_MOD_PATH=${deb_img_dir} modules_sign
>>> +}
>>> +
>>> +install_kmods_debug() {
>>> +    [ -n "${CONFIG_DEBUG_INFO}" ] || return 0
>>> +
>>> +    kmod_inst_dir=${deb_img_dir}/lib/modules
>>> +    kmod_debug_dir=${deb_dbg_dir}/usr/lib/debug
>>> +
>>> +    # copy kernels modules to usr/lib/debug
>>> +    mkdir -p ${kmod_debug_dir}
>>> +    tar -C ${kmod_inst_dir}/ -cO --exclude='modules.*' . | tar -C ${kmod_debug_dir}/ -xf -
>>> +    # strip everything but debug sections for modules in usr/lib/debug
>>> +    find ${kmod_debug_dir} -name *.ko -exec ${CROSS_COMPILE}objcopy --only-keep-debug {} \;
>>> +    # and strip debug sections from modules in lib/modules
>>> +    find ${kmod_inst_dir} -name *.ko -exec ${CROSS_COMPILE}objcopy --strip-debug {} \;
>>> +
>>> +    # re-sign stripped kernel modules
>>> +    kmods_sign
>>> +}
>>> +
>>> +headers_check() {
>>> +    ${MAKE} O=${O} headers_check
>>> +}
>>> +
>>> +libc_headers() {
>>> +    mkdir -p ${deb_libc_hdr_dir}
>>> +    ${MAKE} O=${O} headers_install INSTALL_HDR_PATH=${deb_libc_hdr_dir}/usr
>>> +    host_arch=$(dpkg-architecture -a${DISTRO_ARCH} -qDEB_HOST_MULTIARCH)
>>> +    mkdir ${deb_libc_hdr_dir}/usr/include/${host_arch}
>>> +    mv ${deb_libc_hdr_dir}/usr/include/asm ${deb_libc_hdr_dir}/usr/include/${host_arch}/
>>> +}
>>> +
>>> +# the kernel does not seem to provide a way to cross-compile its tools, we however
>>> +# have qemu-user-static binaries in our buildchroot. Create a new build tree for the
>>> +# scripts and override HOSTCC to force a cross-compile
>>> +kernel_tools_build() {
>>> +    odir="${S}/build-scripts"
>>> +    mflags="HOSTCC=${CROSS_COMPILE}gcc O=${odir} NOSTDINC_FLAGS="
>>> +    rm -rf ${odir} && mkdir -p ${odir} && cp ${S}/${KERNEL_BUILD_DIR}/.config ${odir}
>>> +    (unset LD_PRELOAD; cd ${odir} && make -C ${S} ${mflags} olddefconfig scripts)
>>> +    (cd ${odir}; find scripts -type f -executable -exec file {} \;|grep ELF|cut -d: -f1) >${src_hdr_files}
>>> +    tar -C ${odir} -cf - -T - <${src_hdr_files} | tar -C ${destdir} -xf -
>>> +}
>>> +
>>> +kernel_tools() {
>>> +    # remove object files
>>> +    find ${destdir}/scripts -type f -name '*.o' |xargs rm -f
>>> +
>>> +    # we're all done if we aren't cross-compiling
>>> +    [ -n "${CROSS_COMPILE}" ] || return 0
>>> +
>>> +    # remove ELF executables from the linux-headers package
>>> +    find ${destdir}/scripts -type f -exec file {} \;|grep ELF|cut -d: -f1|xargs rm -fv
>>> +
>>> +    # cross-compile kernel tools to be shipped with linux-headers
>>> +    kernel_tools_build
>>> +}
>>> +
>>> +kernel_headers() {
>>> +    destdir=${deb_kern_hdr_dir}/${KERNEL_HEADERS_DIR}
>>> +    src_hdr_files=$(mktemp)
>>> +    obj_hdr_files=$(mktemp)
>>> +
>>> +    mkdir -p ${destdir}
>>> +    mkdir -p ${deb_kern_hdr_dir}/lib/modules/${PV}
>>> +
>>> +    (cd ${S}; find . -name 'Makefile*' -o -name 'Kconfig*' -o -name '*.pl') >>${src_hdr_files}
>>> +    (cd ${S}; find arch/*/include include scripts -type f -o -type l) >>${src_hdr_files}
>>> +    (cd ${S}; find arch/${ARCH} -name module.lds -o -name Kbuild.platforms -o -name Platform) >>${src_hdr_files}
>>> +    (cd ${S}; find $(find arch/${ARCH} -name include -o -name scripts -type d) -type f) >>${src_hdr_files}
>>> +
>>> +    (cd ${O}; find arch/${ARCH}/include Module.symvers include scripts -type f) >>${obj_hdr_files}
>>> +    if [ -n "${CONFIG_STACK_VALIDATION}" ]; then
>>> +        (cd ${O}; find tools/objtool -type f -executable) >>${obj_hdr_files}
>>> +    fi
>>> +    if [ -n "${CONFIG_GCC_PLUGINS}" ]; then
>>> +        (cd ${O}; find scripts/gcc-plugins -name *.so -o -name gcc-common.h) >>${obj_hdr_files}
>>> +    fi
>>> +
>>> +    # deploy files that were matched above
>>> +    tar -C ${S} -cf - -T - <${src_hdr_files} | tar -C ${destdir} -xf -
>>> +    tar -C ${O} -cf - -T - <${obj_hdr_files} | tar -C ${destdir} -xf -
>>> +
>>> +    # add the kernel config
>>> +    cp ${O}/${KCONF} ${destdir}/.config
>>> +
>>> +    # handle kernel development tools
>>> +    kernel_tools
>>> +
>>> +    # create symlinks
>>> +    ln -sf /${KERNEL_HEADERS_DIR} ${deb_kern_hdr_dir}/lib/modules/${PV}/build
>>> +}
>>> +
>>> +install_headers() {
>>> +    headers_check
>>> +    libc_headers
>>> +    kernel_headers
>>> +}
>>> +
>>> +main install ${*}
>>> diff --git a/meta/recipes-kernel/linux/files/debian/linux-image.postinst.tmpl b/meta/recipes-kernel/linux/files/debian/linux-image.postinst.tmpl
>>> new file mode 100644
>>> index 0000000..fd89121
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/linux-image.postinst.tmpl
>>> @@ -0,0 +1,22 @@
>>> +#!/bin/sh
>>> +
>>> +set -e
>>> +set -x
>>> +
>>> +if [ -f /lib/modules/${PV}/.fresh-install ]; then
>>> +	change=install
>>> +else
>>> +	change=upgrade
>>> +fi
>>> +
>>> +linux-update-symlinks $change ${PV} /boot/${KERNEL_FILE}-${PV}
>>> +rm -f /lib/modules/${PV}/.fresh-install
>>> +
>>> +# Pass maintainer script parameters to hook scripts
>>> +export DEB_MAINT_PARAMS="$*"
>>> +
>>> +# Tell initramfs builder whether it's wanted
>>> +export INITRD=Yes
>>
>> I've noticed while hacking my version that this should follow
>> CONFIG_BLK_DEV_INITRD.
>>
>>> +
>>> +test -d /etc/kernel/postinst.d && run-parts --arg="${PV}" --arg="/boot/${KERNEL_FILE}-${PV}" /etc/kernel/postinst.d
>>> +exit 0
>>> diff --git a/meta/recipes-kernel/linux/files/debian/linux-image.postrm.tmpl b/meta/recipes-kernel/linux/files/debian/linux-image.postrm.tmpl
>>> new file mode 100644
>>> index 0000000..9d88218
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/linux-image.postrm.tmpl
>>> @@ -0,0 +1,18 @@
>>> +#!/bin/sh
>>> +  
>>> +set -e
>>> +
>>> +rm -f /lib/modules/${PV}/.fresh-install
>>> +
>>> +if [ "$1" != upgrade ] && command -v linux-update-symlinks >/dev/null; then
>>> +	linux-update-symlinks remove ${PV} /boot/${KERNEL_FILE}-${PV}
>>> +fi
>>> +
>>> +# Pass maintainer script parameters to hook scripts
>>> +export DEB_MAINT_PARAMS="$*"
>>> +
>>> +# Tell initramfs builder whether it's wanted
>>> +export INITRD=Yes
>>> +
>>> +test -d /etc/kernel/postrm.d && run-parts --arg="${PV}" --arg="/boot/${KERNEL_FILE}-${PV}" /etc/kernel/postrm.d
>>> +exit 0
>>> diff --git a/meta/recipes-kernel/linux/files/debian/rules.tmpl b/meta/recipes-kernel/linux/files/debian/rules.tmpl
>>
>> There is quite some duplication between postinst and postrm already.
>> Moreover, I think you are missing preinst and prerm. I think all four
>> should probably be generated from one template.
>>
>>> new file mode 100755
>>> index 0000000..93c8a5b
>>> --- /dev/null
>>> +++ b/meta/recipes-kernel/linux/files/debian/rules.tmpl
>>> @@ -0,0 +1,39 @@
>>> +#!/usr/bin/make -f
>>> +
>>> +export CROSS_COMPILE=$(DEB_HOST_GNU_TYPE)-
>>> +
>>> +O:=$(CURDIR)/${KERNEL_BUILD_DIR}
>>> +S:=$(CURDIR)
>>> +deb_top_dir:=$(S)/debian
>>> +
>>> +DH_VERBOSE=1
>>> +
>>> +# Dynamic variables to be passed to Isar build scripts
>>> +isar_env=$(strip \
>>> +	export CROSS_COMPILE='$(CROSS_COMPILE)' && \
>>> +	export MAKE='$(MAKE)' && \
>>> +	export O='${O}' \
>>> +	export S='${S}' \
>>> +)
>>> +
>>> +%:
>>> +	dh $(@)
>>> +
>>> +.PHONY: override_dh_auto_clean
>>> +override_dh_auto_clean:
>>> +	$(isar_env) && sh $(deb_top_dir)/isar/clean
>>> +
>>> +.PHONY: override_dh_auto_build
>>> +override_dh_auto_build:
>>> +	$(isar_env) && sh $(deb_top_dir)/isar/build
>>> +
>>> +override_dh_auto_install:
>>> +	$(isar_env) && sh $(deb_top_dir)/isar/install
>>> +
>>> +.PHONY: override_dh_auto_test
>>> +override_dh_auto_test:
>>> +	true
>>> +
>>> +PHONY: override_dh_strip
>>> +override_dh_strip:
>>> +	dh_strip -Xvmlinux --no-automatic-dbgsym
>>> diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
>>> index ca91f64..36086be 100644
>>> --- a/meta/recipes-kernel/linux/linux-custom.inc
>>> +++ b/meta/recipes-kernel/linux/linux-custom.inc
>>> @@ -2,22 +2,104 @@
>>>  #
>>>  # This software is a part of ISAR.
>>>  # Copyright (c) Siemens AG, 2018
>>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>>>  #
>>>  # SPDX-License-Identifier: MIT
>>>  
>>> -FILESEXTRAPATHS_prepend := "${FILE_DIRNAME}/files:"
>>> +# Settings that would typically be done from the custom kernel recipe
>>> +# -------------------------------------------------------------------
>>>  
>>>  DESCRIPTION ?= "Custom kernel"
>>> +MAINTAINER ?= "isar-users <isar-users@googlegroups.com>"
>>> +
>>> +KBUILD_DEPENDS ?= "build-essential:native, \
>>> +                   libelf-dev:native, \
>>> +                   libncurses-dev:native, \
>>> +                   libssl-dev:native, \
>>> +                   bc, \
>>> +                   bison, \
>>> +                   cpio, \
>>> +                   flex, \
>>> +                   git, \
>>> +                   kmod, \
>>> +                   libssl-dev,"
>>> +
>>> +KERNEL_DEBIAN_DEPENDS ?= "initramfs-tools | linux-initramfs-tool, \
>>> +                          kmod, \
>>> +                          linux-base (>= 4.3~),"
>>> +
>>> +KERNEL_HEADERS_DEBIAN_DEPENDS ?= "libc6, \
>>> +                                  libssl1.1,"
>>> +
>>> +KERNEL_LIBC_DEV_DEPLOY ?= "0"
>>> +
>>> +# Settings that may be changed on a per distro, machine or layer basis
>>> +# --------------------------------------------------------------------
>>> +
>>> +KERNEL_DTB_DIR ?= "usr/lib/linux-${KERNEL_NAME_PROVIDED}-${PV}"
>>> +KERNEL_HEADERS_DIR ?= "usr/src/linux-headers-${PV}"
>>>  
>>> -KERNEL_NAME_PROVIDED ?= "${@ d.getVar('PN', True).partition('linux-')[2]}"
>>>  KERNEL_DEFCONFIG ?= ""
>>>  
>>> +# Add our template meta-data to the sources
>>> +FILESEXTRAPATHS_prepend := "${FILE_DIRNAME}/files:"
>>> +SRC_URI += "file://debian"
>>> +
>>> +# Variables and files that make our templates
>>> +# -------------------------------------------
>>> +
>>> +TEMPLATE_FILES += "                  \
>>> +    debian/control.tmpl              \
>>> +    debian/isar/build.tmpl           \
>>> +    debian/isar/clean.tmpl           \
>>> +    debian/isar/common.tmpl          \
>>> +    debian/isar/install.tmpl         \
>>> +    debian/linux-image.postinst.tmpl \
>>> +    debian/linux-image.postrm.tmpl   \
>>> +    debian/rules.tmpl                \
>>> +"
>>> +
>>> +TEMPLATE_VARS += "                \
>>> +    KBUILD_DEPENDS                \
>>> +    KERNEL_ARCH                   \
>>> +    KERNEL_DEBIAN_DEPENDS         \
>>> +    KERNEL_BUILD_DIR              \
>>> +    KERNEL_DTB_DIR                \
>>> +    KERNEL_FILE                   \
>>> +    KERNEL_HEADERS_DEBIAN_DEPENDS \
>>> +    KERNEL_HEADERS_DIR            \
>>> +    KERNEL_NAME_PROVIDED          \
>>> +"
>>> +
>>> +inherit dpkg
>>> +inherit template
>>> +
>>> +# Derive name of the kernel packages from the name of this recipe
>>> +KERNEL_NAME_PROVIDED ?= "${@ d.getVar('PN', True).partition('linux-')[2]}"
>>> +
>>> +# Make bitbake know we will be producing linux-image and linux-headers packages
>>>  python() {
>>>      kernel_name = d.getVar("KERNEL_NAME_PROVIDED", True)
>>>      d.setVar('PROVIDES', 'linux-image-' + kernel_name + ' ' + \
>>>                           'linux-headers-' + kernel_name)
>>>  }
>>>  
>>> +def get_kernel_arch(d):
>>> +    distro_arch = d.getVar("DISTRO_ARCH")
>>> +    if distro_arch == "amd64":
>>> +        kernel_arch = "x86"
>>> +    elif distro_arch == "arm64":
>>> +        kernel_arch = "arm64"
>>> +    elif distro_arch == "armhf":
>>> +        kernel_arch = "arm"
>>> +    elif distro_arch == "mipsel":
>>> +        kernel_arch = "mips"
>>> +    else:
>>> +        kernel_arch = ""
>>> +    return kernel_arch
>>> +
>>> +KERNEL_ARCH ??= "${@get_kernel_arch(d)}"
>>> +
>>>  def config_fragments(d):
>>>      fragments = []
>>>      sources = d.getVar("SRC_URI").split()
>>> @@ -31,57 +113,35 @@ def config_fragments(d):
>>>              fragments.append(local)
>>>      return fragments
>>>  
>>> -inherit dpkg-base
>>> -
>>> -SRC_URI += "file://build-kernel.sh"
>>> +do_prepare_build_prepend() {
>>> +	# copy meta-data over to source tree
>>> +	rm -rf ${S}/debian
>>> +	cp -r ${WORKDIR}/debian ${S}/
>>>  
>>> -KBUILD_DEPENDS ?= " \
>>> -    build-essential:native \
>>> -    libssl-dev \
>>> -    libelf-dev \
>>> -    bc \
>>> -    git \
>>> -    kmod \
>>> -    bison \
>>> -    flex \
>>> -    cpio \
>>> -    libncurses-dev"
>>> -KERNEL_DEBIAN_DEPENDS ?= "initramfs-tools | linux-initramfs-tool, kmod, linux-base (>= 4.3~)"
>>> -KERNEL_HEADERS_DEBIAN_DEPENDS ?= "libc6, libssl1.1"
>>> +	# remove templates from the source tree
>>> +	find ${S}/debian -name *.tmpl | xargs rm -f
>>>  
>>> -KERNEL_LIBC_DEV_DEPLOY ?= "0"
>>> +	# rename install/remove hooks to match user-specified name for our linux-image package
>>> +	mv ${S}/debian/linux-image.postinst ${S}/debian/linux-image-${KERNEL_NAME_PROVIDED}.postinst
>>> +	mv ${S}/debian/linux-image.postrm ${S}/debian/linux-image-${KERNEL_NAME_PROVIDED}.postrm
>>>  
>>> -do_install_builddeps() {
>>> -	dpkg_do_mounts
>>> -	E="${@ bb.utils.export_proxies(d)}"
>>> -	sudo -E chroot ${BUILDCHROOT_DIR} \
>>> -		apt-get update \
>>> -			-o Dir::Etc::SourceList="sources.list.d/isar-apt.list" \
>>> -			-o Dir::Etc::SourceParts="-" \
>>> -			-o APT::Get::List-Cleanup="0"
>>> -	sudo -E chroot ${BUILDCHROOT_DIR} \
>>> -		apt-get install \
>>> -			-y -o Debug::pkgProblemResolver=yes \
>>> -			--no-install-recommends ${KBUILD_DEPENDS}
>>> -	dpkg_undo_mounts
>>> +	# produce a changelog for our kernel build
>>> +	deb_add_changelog
>>>  }
>>>  
>>> -addtask install_builddeps after do_prepare_build before do_dpkg_build
>>> -# apt and reprepro may not run in parallel, acquire the Isar lock
>>> -do_install_builddeps[lockfiles] += "${REPO_ISAR_DIR}/isar.lock"
>>> -
>>> -addtask devshell after do_install_builddeps
>>> +# build directory for our "full" kernel build
>>> +KERNEL_BUILD_DIR = "build-full"
>>>  
>>> -dpkg_runbuild() {
>>> -	chmod +x ${WORKDIR}/build-kernel.sh
>>> -	KERNEL_CONFIG_TARGET="${KERNEL_DEFCONFIG}"
>>> +dpkg_configure_kernel() {
>>> +	config_target="${KERNEL_DEFCONFIG}"
>>> +	rm -rf ${S}/${KERNEL_BUILD_DIR} && mkdir -p ${S}/${KERNEL_BUILD_DIR}
>>>  	if [ -n "${KERNEL_DEFCONFIG}" ]; then
>>>  		if [ -e "${WORKDIR}/${KERNEL_DEFCONFIG}" ]; then
>>> -			cp ${WORKDIR}/${KERNEL_DEFCONFIG} ${S}/.config
>>> -			KERNEL_CONFIG_TARGET="olddefconfig"
>>> +			cp ${WORKDIR}/${KERNEL_DEFCONFIG} ${S}/${KERNEL_BUILD_DIR}/.config
>>> +			config_target="olddefconfig"
>>>  		fi
>>>  	else
>>> -		KERNEL_CONFIG_TARGET="defconfig"
>>> +		config_target="defconfig"
>>>  	fi
>>>  
>>>  	# copy config fragments over to the kernel tree
>>> @@ -92,21 +152,23 @@ dpkg_runbuild() {
>>>  		mkdir -p ${S}/debian/fragments
>>>  		(cd ${WORKDIR} && cp ${src_frags} ${S}/debian/fragments/)
>>>  	fi
>>> -	export KERNEL_FRAGMENTS="${out_frags}"
>>>  
>>> -	E="${@ bb.utils.export_proxies(d)}"
>>> -
>>> -	export PV=${PV}
>>> -	export KERNEL_NAME=${KERNEL_NAME_PROVIDED}
>>> -
>>> -	export KBUILD_DEPENDS="${KBUILD_DEPENDS}"
>>> -	export KERNEL_CONFIG_TARGET
>>> -	export KERNEL_DEBIAN_DEPENDS="${KERNEL_DEBIAN_DEPENDS}"
>>> -	export KERNEL_FILE="${KERNEL_FILE}"
>>> -	export KERNEL_HEADERS_DEBIAN_DEPENDS="${KERNEL_HEADERS_DEBIAN_DEPENDS}"
>>> +	sudo -E chroot --userspec=$(id -u):$(id -g) ${BUILDCHROOT_DIR} sh -c " \
>>> +		export ARCH=${KERNEL_ARCH} &&                                  \
>>> +		cd ${PP}/${PPS} &&                                             \
>>> +		make O=${KERNEL_BUILD_DIR} ${config_target} &&                 \
>>> +		./scripts/kconfig/merge_config.sh                              \
>>> +			-O ${KERNEL_BUILD_DIR}/                                \
>>> +			${KERNEL_BUILD_DIR}/.config                            \
>>> +			${out_frags}                                           \
>>> +        "
>>> +}
>>>  
>>> -	sudo -E chroot --userspec=$( id -u ):$( id -g ) ${BUILDCHROOT_DIR} ${PP}/build-kernel.sh ${PP}/${PPS} ${DISTRO_ARCH}
>>> +dpkg_runbuild_prepend() {
>>> +	dpkg_configure_kernel
>>> +}
>>>  
>>> +dpkg_runbuild_append() {
>>>  	if [ "${KERNEL_LIBC_DEV_DEPLOY}" != "1" ]; then
>>>  		rm -f ${WORKDIR}/linux-libc-dev_${PV}*.deb
>>>  	fi
>>>
>>
>> Valuable step forward! I still need to check some more details against
>> my unfinished prototype, but it seems it generally a superset of it.
> 
> Found a first difference:
> 
>         if $(call is_enabled,CONFIG_OF_EARLY_FLATTREE) && \
>            [ -d arch/${ARCH}/boot/dts ]; then \
>                 $(MAKE) INSTALL_DTBS_PATH=debian/tmp/usr/lib/linux-image-${PV} dtbs_install; \
>         fi

Ah, you have the installation, just the condition is inaccurate. IIRC,
CONFIG_OF_EARLY_FLATTREE comes directly from the upstream packaging rules.

Jan

-- 
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux