Re: [PATCH v2 1/5] linux-custom: Split up binaries from kernel headers to kbuild package

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

On 20.12.22 18:09, Koch, Stefan (DI PA DCP R&D 3) wrote:
> This patch does introduce specific kernel kbuild packages that
> ship the "scripts" and "tools" binaries.
> The kernel headers fulfill this using symlinks to point
> to the "scripts" and "tools" of the kernel kbuild package.
> 
> This is already known from debian kernel packages structure:
> - Generate a kernel headers package without binaries
> - Create kernel kbuild packages that
>   ship the "scripts" and "tools" binaries
> - Using symlinks to point to the "scripts"
>   and "tools" binaries
> 
> Signed-off-by: Stefan Koch <stefan-koch@siemens.com>
> ---
>  .../linux/files/debian/control.tmpl           |  9 +++-
>  .../linux/files/debian/isar/common.tmpl       |  2 +
>  .../linux/files/debian/isar/install.tmpl      | 51 +++++++++++++++----
>  meta/recipes-kernel/linux/linux-custom.inc    |  4 ++
>  4 files changed, 54 insertions(+), 12 deletions(-)
> 
> diff --git a/meta/recipes-kernel/linux/files/debian/control.tmpl b/meta/recipes-kernel/linux/files/debian/control.tmpl
> index dd0b624..b19ca2c 100644
> --- a/meta/recipes-kernel/linux/files/debian/control.tmpl
> +++ b/meta/recipes-kernel/linux/files/debian/control.tmpl
> @@ -26,7 +26,7 @@ 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
> + 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-${KERNEL_NAME_PROVIDED}-dbg
> @@ -35,3 +35,10 @@ Architecture: any
>  Description: Linux kernel debugging symbols for @KR@
>   This package will come in handy if you need to debug the kernel. It provides
>   all the necessary debug symbols for the kernel and its modules.
> +
> +Package: linux-kbuild-${KERNEL_NAME_PROVIDED}
> +Architecture: any
> +Depends: ${perl:Depends}, ${shlib:Depends}
> +Description: ${KERNEL_NAME_PROVIDED} Linux kbuild scripts and tools for @KR@
> + This package provides kernel kbuild scripts and tools for @KR@
> + This is useful for people who need to build external modules
> diff --git a/meta/recipes-kernel/linux/files/debian/isar/common.tmpl b/meta/recipes-kernel/linux/files/debian/isar/common.tmpl
> index 52ebebb..f4c0519 100644
> --- a/meta/recipes-kernel/linux/files/debian/isar/common.tmpl
> +++ b/meta/recipes-kernel/linux/files/debian/isar/common.tmpl
> @@ -9,6 +9,7 @@ ARCH=${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
> +KERNEL_PKG_KERN_KBUILD=linux-kbuild-${KERNEL_NAME_PROVIDED}
>  
>  # Constants
>  KCONF=.config
> @@ -19,6 +20,7 @@ deb_img_dir=${deb_top_dir}/${KERNEL_PKG_IMAGE}
>  deb_dbg_dir=${deb_img_dir}-dbg
>  deb_kern_hdr_dir=${deb_top_dir}/${KERNEL_PKG_KERN_HEADERS}
>  deb_libc_hdr_dir=${deb_top_dir}/${KERNEL_PKG_LIBC_HEADERS}
> +deb_kern_kbuild_dir=${deb_top_dir}/${KERNEL_PKG_KERN_KBUILD}
>  
>  # Array of packages to be generated
>  declare -A kern_pkgs
> diff --git a/meta/recipes-kernel/linux/files/debian/isar/install.tmpl b/meta/recipes-kernel/linux/files/debian/isar/install.tmpl
> index 8a604e4..236b67c 100644
> --- a/meta/recipes-kernel/linux/files/debian/isar/install.tmpl
> +++ b/meta/recipes-kernel/linux/files/debian/isar/install.tmpl
> @@ -33,6 +33,7 @@ do_install() {
>      # Trace what we do here
>      set -x
>  
> +    # Run the install steps
>      install_image
>      if [ "${ARCH}" != "um" ]; then
>          install_config
> @@ -43,6 +44,10 @@ do_install() {
>      install_kmods
>      install_headers
>  
> +    # Cleanup and install kernel scripts and tools
> +    rm -rf ${deb_kern_kbuild_dir}
> +    install_kbuild ${deb_kern_kbuild_dir}
> +
>      # Stop tracing
>      set +x
>  }
> @@ -168,21 +173,15 @@ kernel_headers() {
>      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 . -not -path './scripts/*' -a -not -path './tools/*' -a \( -name 'Makefile*' -o -name 'Kconfig*' -o -name '*.pl' \)) >>${src_hdr_files}
> +    (cd ${S}; find arch/*/include include -type f -o -type l) >>${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) >>${src_hdr_files}
>  
>      if [ -n "${CONFIG_MODULES}" ]; then
>          echo Module.symvers >> ${obj_hdr_files}
>      fi
> -    (cd ${O}; find arch/${ARCH}/include include scripts -type f) >>${obj_hdr_files}
> -    if [ -n "${CONFIG_STACK_VALIDATION}" -o -n "${CONFIG_HAVE_OBJTOOL}" ]; 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
> +    (cd ${O}; find arch/${ARCH}/include include -type f) >>${obj_hdr_files}
>  
>      # deploy files that were matched above
>      tar -C ${S} -cf - -T - <${src_hdr_files} | tar -C ${destdir} -xf -
> @@ -191,8 +190,11 @@ kernel_headers() {
>      # add the kernel config
>      cp ${O}/${KCONF} ${destdir}/.config
>  
> -    # handle kernel development tools
> -    kernel_tools
> +    # add symlink to scripts and tools directories
> +    ln -sf ../../lib/linux-kbuild-${krel}/scripts ${destdir}/scripts
> +    if [ -n "${CONFIG_STACK_VALIDATION}" -o -n "${CONFIG_HAVE_OBJTOOL}" ]; then
> +        ln -sf ../../lib/linux-kbuild-${krel}/tools ${destdir}/tools

Is Debian using relative links for this as well? Or rather absolute
ones. We use a absolute one below.

> +    fi
>  
>      # create symlinks
>      ln -sf /${kernel_headers_dir} ${deb_kern_hdr_dir}/lib/modules/${krel}/build
> @@ -206,4 +208,31 @@ install_headers() {
>      kernel_headers
>  }
>  
> +install_kbuild() {
> +    kernel_kbuild_dir=usr/lib/linux-kbuild-${krel}
> +    destdir=${1}/${kernel_kbuild_dir}
> +    src_kbuild_files=$(mktemp)
> +    obj_kbuild_files=$(mktemp)
> +
> +    mkdir -p ${destdir}
> +
> +    (cd ${S}; find . -path './scripts/*' -a -path './tools/*' -a \( -name 'Makefile*' -o -name 'Kconfig*' -o -name '*.pl' \)) >>${src_kbuild_files}
> +    (cd ${S}; find scripts -type f -o -type l) >>${src_kbuild_files}
> +
> +    (cd ${O}; find scripts -type f) >>${obj_kbuild_files}
> +    if [ -n "${CONFIG_STACK_VALIDATION}" -o -n "${CONFIG_HAVE_OBJTOOL}" ]; then
> +        (cd ${O}; find tools/objtool -type f -executable) >>${obj_kbuild_files}
> +    fi
> +    if [ -n "${CONFIG_GCC_PLUGINS}" ]; then
> +        (cd ${O}; find scripts/gcc-plugins -name *.so -o -name gcc-common.h) >>${obj_kbuild_files}
> +    fi
> +
> +    # deploy files that were matched above
> +    tar -C ${S} -cf - -T - <${src_kbuild_files} | tar -C ${destdir} -xf -
> +    tar -C ${O} -cf - -T - <${obj_kbuild_files} | tar -C ${destdir} -xf -
> +
> +    # handle kernel development tools
> +    kernel_tools
> +}
> +
>  main install ${*}
> diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
> index 96f0afc..dbda755 100644
> --- a/meta/recipes-kernel/linux/linux-custom.inc
> +++ b/meta/recipes-kernel/linux/linux-custom.inc
> @@ -96,6 +96,10 @@ python() {
>      kernel_name = d.getVar("KERNEL_NAME_PROVIDED", True)
>      d.setVar('PROVIDES', 'linux-image-' + kernel_name + ' ' + \
>                           'linux-headers-' + kernel_name)
> +    headers_depends = "linux-kbuild-" + kernel_name
> +
> +    # Set dependency for kernel headers
> +    d.appendVar("KERNEL_HEADERS_DEBIAN_DEPENDS", headers_depends)
>  }
>  
>  def get_kernel_arch(d):

Except for the one question above, this commit looks good to me. But
maybe Cedric has some comments as well, given that he once wrote
significant parts of this.

Jan

-- 
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