Re: [PATCH L-C v3 7/7] linux-custom: rewrite to no longer depend on the kernel's builddeb

[Cedric Hombourger <Cedric_Hombourger@mentor.com>]

On 11/8/19 8:19 AM, Jan Kiszka wrote:
> On 08.11.19 08:07, 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                          |  80 +++++++
>>   .../linux/files/build-kernel.sh               | 128 -----------
>>   meta/recipes-kernel/linux/files/debian/compat |   1 +
>>   .../linux/files/debian/control.tmpl           |  37 ++++
>>   .../linux/files/debian/isar/build.tmpl        |  45 ++++
>>   .../linux/files/debian/isar/clean.tmpl        |  21 ++
>>   .../linux/files/debian/isar/common.tmpl       |  50 +++++
>>   .../linux/files/debian/isar/install.tmpl      | 206 ++++++++++++++++++
>>   .../files/debian/linux-image.postinst.tmpl    |  29 +++
>>   .../files/debian/linux-image.postrm.tmpl      |  35 +++
>>   .../files/debian/linux-image.preinst.tmpl     |  25 +++
>>   .../linux/files/debian/linux-image.prerm.tmpl |  21 ++
>>   .../linux/files/debian/rules.tmpl             |  39 ++++
>>   meta/recipes-kernel/linux/linux-custom.inc    | 180 ++++++++++-----
>>   14 files changed, 712 insertions(+), 185 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/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 100644 
>> meta/recipes-kernel/linux/files/debian/linux-image.preinst.tmpl
>>   create mode 100644 
>> meta/recipes-kernel/linux/files/debian/linux-image.prerm.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..31319d4
>> --- /dev/null
>> +++ b/doc/custom_kernel.md
>> @@ -0,0 +1,80 @@
>> +# Custom kernel recipe for Isar
>> +
>> +## Contents
>> +
>> + - [Summary](#summary)
>> + - [Features](#features)
>> + - [Future](#future)
>> + - [Examples](#examples)
>> +
>> +## Summary
>> +
>> +Isar provides a recipe to build custom kernels for Debian-based 
>> distributions.
>> +It uses templates to generate the debian meta-data (such as 
>> debian/control) and
>> +Debian's [BuildProfiles](https://wiki.debian.org/BuildProfileSpec) 
>> to handle
>> +some of the distro specific variations. It should be noted that Isar 
>> has moved
>> +away from using the kernel's builddeb script since it would not 
>> generate all
>> +the packages we need (and in particular perf).
>> +
>> +## Features
>> +
>> +The linux-custom recipe provides support for:
>> +
>> + 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` via
>> +    `KERNEL_DEFCONFIG`
>> +
>> + 3. Integrate 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
>> +
>> + 10. Produce a `linux-libc-dev` package to support user-land builds
>> +
>> + 11. Only build/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)
>> +
>> +## Future
>> +
>> +In the future, the recipe may be extended to:
>> +
>> + 1. Package perf
>> +
>> + 2. Support inclusion/build of dts files listed in `SRC_URI`
>> +
>> + 3. Be compatible with Ubuntu
>> +
>> +## Examples
>> +
>> +The linux-custom recipe is currently used by the linux-mainline 
>> package and is
>> +used mainline recipe may be used for some basic testing. This recipe 
>> is being
>> +used by the following machines:
>> +
>> + * de0-nano-soc
>> + * qemumipsel
>> 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..d55096b
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/control.tmpl
>> @@ -0,0 +1,37 @@
>> +Source: linux-${KERNEL_NAME_PROVIDED}
>> +Section: kernel
>> +Priority: optional
>> +Maintainer: ${MAINTAINER}
>> +Build-Depends: bc, kmod, cpio, ${KBUILD_DEPENDS}
>> +Homepage: http://www.kernel.org/
>> +
>> +Package: linux-image-${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 ${DISTRO_ARCH}
>> + .
>> + This is useful for people who need to build external modules
>> +
>> +Package: linux-libc-dev
>> +Build-Profiles: <!nolibcdev>
>> +Section: devel
>> +Provides: linux-kernel-headers
>> +Architecture: any
>> +Description: Linux support headers for userspace development
>> + This package provides userspaces headers from the Linux kernel.  
>> These headers
>> + are used by the installed headers for GNU glibc and other system 
>> libraries.
>> +
>> +Package: linux-image-${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/isar/build.tmpl 
>> b/meta/recipes-kernel/linux/files/debian/isar/build.tmpl
>> new file mode 100644
>> index 0000000..4ea18d5
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/isar/build.tmpl
>> @@ -0,0 +1,45 @@
>> +#!/bin/bash
>> +# 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
>> +
>> +    # Process existing kernel configuration to make sure it is complete
>> +    # (use defaults for options that were not specified)
>> +    ${MAKE} O=${KERNEL_BUILD_DIR} olddefconfig prepare || exit ${?}
>> +
>> +    # Check if the recipe's PV makes sense
>> +    KR=$(${MAKE} O=${KERNEL_BUILD_DIR} -s --no-print-directory 
>> kernelrelease)
>> +    eval $(grep ^CONFIG_LOCALVERSION= ${KERNEL_BUILD_DIR}/${KCONF} 
>> || true)
>> +    if [ "${PV}" != "${KR}" -a "${PV}${CONFIG_LOCALVERSION}" != 
>> "${KR}" ]; then
>> +        echo "ERROR: Recipe PV (${PV}) does not seem to match the 
>> kernelrelease (${KR})!" 1>&2
>> +        echo "ERROR: Make sure the kernel version in your PV setting 
>> and/or CONFIG_LOCALVERSION are aligned" 1>&2
>> +        exit 1
>> +    fi
>> +
>> +    # Trace what we do here
>> +    set -x
>> +
>> +    # 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..f903987
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/isar/clean.tmpl
>> @@ -0,0 +1,21 @@
>> +#!/bin/bash
>> +# 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}
>> +    rm -rf ${deb_libc_hdr_dir}
>> +
>> +    # Stop tracing
>> +    set +x
>> +}
>> +
>> +main clean ${*}
>> diff --git a/meta/recipes-kernel/linux/files/debian/isar/common.tmpl 
>> b/meta/recipes-kernel/linux/files/debian/isar/common.tmpl
>> new file mode 100644
>> index 0000000..44f67b3
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/isar/common.tmpl
>> @@ -0,0 +1,50 @@
>> +#!/bin/bash
>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>> +# SPDX-License-Identifier: MIT
>> +
>> +# Isar settings
>> +ARCH=${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}
>> +
>> +# Array of packages to be generated
>> +declare -A kern_pkgs
>> +
>> +main() {
>> +    local target=${1}
>> +
>> +    if [ ! -f ${S}/debian/isar/${target} ]; then
>> +        echo "error: ${target} is not a supported build target!" >&2
>> +        return 1
>> +    fi
>> +
>> +    # create do_<x> variables for each package to be generated
>> +    for p in $(unset DEB_HOST_ARCH; dh_listpackages); do
>> +        kern_pkgs["${p}"]="1"
>> +    done
>> +
>> +    # variables to be exported
>> +    export ARCH
>> +
>> +    # are we cross-compiling?
>> +    BUILD_ARCH=$(dpkg-architecture -qDEB_BUILD_ARCH)
>> +    if [ "${BUILD_ARCH}" = "${DISTRO_ARCH}" ]; then
>> +        # no, make sure CROSS_COMPILE isn't set
>> +        unset CROSS_COMPILE
>> +    fi
>> +
>> +    # call the actual target script
>> +    do_${target} || return ${?}
>> +}
>> 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..8ccda68
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/isar/install.tmpl
>> @@ -0,0 +1,206 @@
>> +#!/bin/bash
>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>> +# SPDX-License-Identifier: MIT
>> +
>> +# Load common stuff
>> +. ${S}/debian/isar/common || exit ${?}
>> +
>> +# Stop on error
>> +set -e
>> +
>> +do_install() {
>> +
>> +    # check if our kernel was configured
>> +    if [ ! -f "${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)"
>> +    krel="$(${MAKE} O=${O} -s --no-print-directory kernelrelease)"
>> +    case "${ARCH}" in
>> +        mips|powerpc) kimage_path="boot/vmlinux-${krel}"    ;;
>> +                  um) kimage_path="usr/bin/vmlinux-${krel}" ;;
>> +                   *) kimage_path="boot/vmlinuz-${krel}"    ;;
>> +    esac
>> +
>> +    print_settings
>> +
>> +    # Trace what we do here
>> +    set -x
>> +
>> +    install_image
>> +    install_hooks
>> +    install_dtbs
>> +    install_kmods
>> +    install_headers
>> +
>> +    # Stop tracing
>> +    set +x
>> +}
>> +
>> +print_settings() {
>> +    cat <<EOF
>> +Install settings:
>> +-----------------
>> +deb_dtb_dir=${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 ${deb_dbg_dir}/usr/lib/debug/lib/modules/${krel}/
>> +    cp ${O}/vmlinux ${deb_dbg_dir}/usr/lib/debug/lib/modules/${krel}/
>> +    # systemtap
>> +    mkdir -p ${deb_dbg_dir}/usr/lib/debug/boot/
>> +    ln -s ../lib/modules/$version/vmlinux 
>> ${deb_dbg_dir}/usr/lib/debug/boot/vmlinux-${krel}
>> +    # kdump-tools
>> +    ln -s lib/modules/${krel}/vmlinux 
>> ${deb_dbg_dir}/usr/lib/debug/vmlinux-${krel}
>> +}
>> +
>> +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 ${deb_img_dir}/etc/kernel/prerm.d
>> +
>> +    initrd="No"
>> +    [ -z "${CONFIG_BLK_DEV_INITRD}" ] || initrd="Yes"
>> +
>> +    for script in postinst postrm preinst prerm; do
>> +        sed -i -e "s,INITRD=[A-Za-z0-9]*,INITRD=${initrd},g" 
>> ${S}/debian/linux-image*.${script}
>> +        sed -i -e "s,version=.*,version=${krel},g" 
>> ${S}/debian/linux-image*.${script}
>> +    done
>> +}
>> +
>> +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 ${deb_img_dir}/lib/modules/${krel}/.fresh-install
>> +    rm -fv ${deb_img_dir}/lib/modules/${krel}/build
>> +    rm -fv ${deb_img_dir}/lib/modules/${krel}/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 ${deb_kern_hdr_dir}/lib/modules/${krel}
>> +
>> +    (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} 
>> ${deb_kern_hdr_dir}/lib/modules/${krel}/build
>> +}
>> +
>> +install_headers() {
>> +    headers_check
>> +    [ -z ${kern_pkgs["linux-libc-headers"]} ] || libc_headers
>> +    kernel_headers
>> +}
>> +
>> +main install ${*}
>> diff --git 
>> a/meta/recipes-kernel/linux/files/debian/linux-image.postinst.tmpl 
>> b/meta/recipes-kernel/linux/files/debian/linux-image.postinst.tmpl
>> new file mode 100644
>> index 0000000..8e8636a
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/linux-image.postinst.tmpl
>> @@ -0,0 +1,29 @@
>> +#!/bin/sh
>> +# based on 
>> https://salsa.debian.org/kernel-team/linux/blob/master/debian/templates/image.postinst.in
>> +
>> +# Tell initramfs builder whether it's wanted
>> +export INITRD=Yes
>> +
>> +version=${PV}
>> +image_path=/boot/${KERNEL_FILE}-${version}
>> +
>> +if [ "$1" != configure ]; then
>> +    exit 0
>> +fi
>> +
>> +depmod $version
>> +
>> +if [ -f /lib/modules/$version/.fresh-install ]; then
>> +    change=install
>> +else
>> +    change=upgrade
>> +fi
>> +linux-update-symlinks $change $version $image_path
>> +rm -f /lib/modules/$version/.fresh-install
>> +
>> +if [ -d /etc/kernel/postinst.d ]; then
>> +    DEB_MAINT_PARAMS="$*" run-parts --report --exit-on-error 
>> --arg=$version \
>> +          --arg=$image_path /etc/kernel/postinst.d
>> +fi
>> +
>> +exit 0
>> diff --git 
>> a/meta/recipes-kernel/linux/files/debian/linux-image.postrm.tmpl 
>> b/meta/recipes-kernel/linux/files/debian/linux-image.postrm.tmpl
>> new file mode 100644
>> index 0000000..4d8a7d9
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/linux-image.postrm.tmpl
>> @@ -0,0 +1,35 @@
>> +#!/bin/sh -e
>> +# based on 
>> https://salsa.debian.org/kernel-team/linux/blob/master/debian/templates/image.postrm.in
>> +
>> +# Tell initramfs builder whether it's wanted
>> +export INITRD=Yes
>> +
>> +version=${PV}
>> +image_path=/boot/${KERNEL_FILE}-${version}
>> +
>> +rm -f /lib/modules/$version/.fresh-install
>> +
>> +if [ "$1" != upgrade ] && command -v linux-update-symlinks 
>> >/dev/null; then
>> +    linux-update-symlinks remove $version $image_path
>> +fi
>> +
>> +if [ -d /etc/kernel/postrm.d ]; then
>> +    DEB_MAINT_PARAMS="$*" run-parts --report --exit-on-error 
>> --arg=$version \
>> +          --arg=$image_path /etc/kernel/postrm.d
>> +fi
>> +
>> +if [ "$1" = purge ]; then
>> +    for extra_file in modules.dep modules.isapnpmap modules.pcimap \
>> +                      modules.usbmap modules.parportmap \
>> +                      modules.generic_string modules.ieee1394map \
>> +                      modules.ieee1394map modules.pnpbiosmap \
>> +                      modules.alias modules.ccwmap modules.inputmap \
>> +                      modules.symbols modules.ofmap \
>> +                      modules.seriomap modules.\*.bin \
>> +              modules.softdep modules.devname; do
>> +    eval rm -f /lib/modules/$version/$extra_file
>> +    done
>> +    rmdir /lib/modules/$version || true
>> +fi
>> +
>> +exit 0
>> diff --git 
>> a/meta/recipes-kernel/linux/files/debian/linux-image.preinst.tmpl 
>> b/meta/recipes-kernel/linux/files/debian/linux-image.preinst.tmpl
>> new file mode 100644
>> index 0000000..7465197
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/linux-image.preinst.tmpl
>> @@ -0,0 +1,25 @@
>> +#!/bin/sh -e
>> +# based on 
>> https://salsa.debian.org/kernel-team/linux/blob/master/debian/templates/image.preinst.in
>> +
>> +# Tell initramfs builder whether it's wanted
>> +export INITRD=Yes
>> +
>> +version=${PV}
>> +image_path=/boot/${KERNEL_FILE}-${version}
>> +
>> +if [ "$1" = abort-upgrade ]; then
>> +    exit 0
>> +fi
>> +
>> +if [ "$1" = install ]; then
>> +    # Create a flag file for postinst
>> +    mkdir -p /lib/modules/$version
>> +    touch /lib/modules/$version/.fresh-install
>> +fi
>> +
>> +if [ -d /etc/kernel/preinst.d ]; then
>> +    DEB_MAINT_PARAMS="$*" run-parts --report --exit-on-error 
>> --arg=$version \
>> +          --arg=$image_path /etc/kernel/preinst.d
>> +fi
>> +
>> +exit 0
>> diff --git 
>> a/meta/recipes-kernel/linux/files/debian/linux-image.prerm.tmpl 
>> b/meta/recipes-kernel/linux/files/debian/linux-image.prerm.tmpl
>> new file mode 100644
>> index 0000000..1992b32
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/linux-image.prerm.tmpl
>> @@ -0,0 +1,21 @@
>> +#!/bin/sh -e
>> +# based on 
>> https://salsa.debian.org/kernel-team/linux/blob/master/debian/templates/image.prerm.in
>> +
>> +# Tell initramfs builder whether it's wanted
>> +export INITRD=Yes
>> +
>> +version=${PV}
>> +image_path=/boot/${KERNEL_FILE}-${version}
>> +
>> +if [ "$1" != remove ]; then
>> +    exit 0
>> +fi
>> +
>> +linux-check-removal $version
>> +
>> +if [ -d /etc/kernel/prerm.d ]; then
>> +    DEB_MAINT_PARAMS="$*" run-parts --report --exit-on-error 
>> --arg=$version \
>> +          --arg=$image_path /etc/kernel/prerm.d
>> +fi
>> +
>> +exit 0
>> diff --git a/meta/recipes-kernel/linux/files/debian/rules.tmpl 
>> b/meta/recipes-kernel/linux/files/debian/rules.tmpl
>> new file mode 100755
>> index 0000000..c024768
>> --- /dev/null
>> +++ b/meta/recipes-kernel/linux/files/debian/rules.tmpl
>> @@ -0,0 +1,39 @@
>> +#!/usr/bin/make -f
>> +
>> +CROSS_COMPILE:=$(DEB_HOST_GNU_TYPE)-
>> +
>> +O:=$(CURDIR)/${KERNEL_BUILD_DIR}
>> +S:=$(CURDIR)
>> +deb_top_dir:=$(S)/debian
>> +
>> +# Dynamic variables to be passed to Isar build scripts
>> +isar_env=$(strip \
>> +    export CROSS_COMPILE='$(CROSS_COMPILE)' && \
>> +    export DEB_BUILD_PROFILES='$(DEB_BUILD_PROFILES)' && \
>> +    export DEB_HOST_GNU_TYPE='$(DEB_HOST_GNU_TYPE)' && \
>> +    export MAKE='$(MAKE)' && \
>> +    export O='${O}' \
>> +    export S='${S}' \
>> +)
>> +
>> +%:
>> +    dh $(@)
>> +
>> +.PHONY: override_dh_auto_clean
>> +override_dh_auto_clean:
>> +    $(isar_env) && bash $(deb_top_dir)/isar/clean
>> +
>> +.PHONY: override_dh_auto_build
>> +override_dh_auto_build:
>> +    $(isar_env) && bash $(deb_top_dir)/isar/build
>> +
>> +override_dh_auto_install:
>> +    $(isar_env) && bash $(deb_top_dir)/isar/install
>> +
>> +.PHONY: override_dh_auto_test
>> +override_dh_auto_test:
>> +    true
>> +
>> +PHONY: override_dh_strip
>> +override_dh_strip:
>> +    dh_strip -Xvmlinux --no-automatic-dbgsym
>> diff --git a/meta/recipes-kernel/linux/linux-custom.inc 
>> b/meta/recipes-kernel/linux/linux-custom.inc
>> index ca91f64..ecf0e66 100644
>> --- a/meta/recipes-kernel/linux/linux-custom.inc
>> +++ b/meta/recipes-kernel/linux/linux-custom.inc
>> @@ -2,22 +2,107 @@
>>   #
>>   # This software is a part of ISAR.
>>   # Copyright (c) Siemens AG, 2018
>> +# Copyright (c) Mentor Graphics, a Siemens business, 2019
>>   #
>>   # SPDX-License-Identifier: MIT
>>   -FILESEXTRAPATHS_prepend := "${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}"
>
> Here is the bug that breaks U-boot setups here: Must be 
> linux-image-${PV} in order to stay compatible with Debian.
>
> Did you compare some content of the new packages against that of the 
> original package build?
>
Yes but I had not anticipated this one as being an issue (so thanks for 
pointing that out). I have limited hardware available here (mostly 
Siemens IPCs or non supported boards such as Xilinx ref boards). will 
check if I can get remote access to some of the boards supported by 
Isar. I have made the change locally and started a build. I hope I can 
check it out on the de0-nano-soc board that we have in meta-isar
> Jan
>
>> +KERNEL_HEADERS_DIR ?= "usr/src/linux-headers-${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/linux-image.preinst.tmpl  \
>> +    debian/linux-image.prerm.tmpl    \
>> +    debian/rules.tmpl                \
>> +"
>> +
>> +TEMPLATE_VARS += "                \
>> +    HOST_ARCH                     \
>> +    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 +116,37 @@ 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
>> +    mv ${S}/debian/linux-image.preinst 
>> ${S}/debian/linux-image-${KERNEL_NAME_PROVIDED}.preinst
>> +    mv ${S}/debian/linux-image.prerm 
>> ${S}/debian/linux-image-${KERNEL_NAME_PROVIDED}.prerm
>>   -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
>> @@ -92,22 +157,23 @@ 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} ${PP}/build-kernel.sh ${PP}/${PPS} ${DISTRO_ARCH}
>> +    sudo -E chroot --userspec=$(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                            \
>> + ${out_frags}                                           \
>> +        "
>> +}
>>   +dpkg_runbuild_prepend() {
>> +    profiles="${BASE_DISTRO}"
>>       if [ "${KERNEL_LIBC_DEV_DEPLOY}" != "1" ]; then
>> -        rm -f ${WORKDIR}/linux-libc-dev_${PV}*.deb
>> +        profiles="${profiles} nolibcdev"
>>       fi
>> +    export DEB_BUILD_PROFILES="${profiles}"
>> +    dpkg_configure_kernel
>>   }
>>
>
>