Re: [PATCH v2 0/5] linux-custom: Split up binaries from kernel headers to kbuild packages

[Uladzimir Bely <ubely@ilbers.de>]

In mail from Tuesday, 20 December 2022 20:09:27 +03 user Koch, Stefan wrote:
> Hi
> 
> This updated v2 patchset implement suggestions from reviewed v1 patchset.
> It's now a set of five patches:
> - linux-custom: Split up binaries from kernel headers to kbuild package
> - sbuild: Support overwriting configured schroot dir
> - dpkg: Add support for additional target and host builds
> - linux-custom: Provide host and target specific kernel kbuild packages
> - docs: Update custom_kernel docs for split up of kernel scripts and tools
> 
> The main use-case was to swap out the binaries
> from the kernel headers into kernel kbuild package.
> This is introduced by the first commit
> "Split up binaries from kernel headers to kbuild package"
> 
> The fourth commit "Provide host and target specific kernel kbuild packages"
> introduces that the binaries could be swapped out into host and target
> specific kernel kbuild packages.
> 
> The main development goals were these:
> 
> 1. Solve already known isar custom kernel
> limitations from doc/custom_kernel.inc
> - kernel headers package does not support both native
>   and cross compilation of kernel modules when cross built
> 
> 2. Honor recommendations for future from doc/custom_kernel.inc
> - Generate kernel headers packages for both host and target
>   when using cross build
> 
> 3. Add extensions known from debian kernel packages structure
> - Generate a kernel headers package without binaries
> - Create specific kernel kbuild packages that
>   will ship the "scripts" and "tools" binaries
> - Use symlinks to point to the "scripts" and "tools" binaries
> 
> 4. Be user friendly
> - Avoid usage of separate kbuild bitbake recipe that may enforce
>   redundant configuration of kernel source definitions with user
>   actions to enable kbuild package generation
> - Use already known way to include linux-custom.inc in just one
>   own bitbake recipe that provides the kernel source definitions
> - Keep known user behavior for existing build configurations: just update
> isar, append "target" (and "host") to ISAR_BUILDS and kbuild packages for
> target and host will be created automatically
> 
> Best regards
> 
> Stefan
> 
> Stefan Koch (5):
>   linux-custom: Split up binaries from kernel headers to kbuild package
>   sbuild: Support overwriting configured schroot dir
>   dpkg: Add support for additional target and host builds
>   linux-custom: Provide host and target specific kernel kbuild packages
>   docs: Update custom_kernel docs for split up of kernel scripts and
>     tools
> 
>  doc/custom_kernel.md                          | 20 +++--
>  meta/classes/dpkg-base.bbclass                | 51 +++++++++++--
>  meta/classes/dpkg.bbclass                     |  2 +-
>  meta/classes/sbuild.bbclass                   |  9 ++-
>  .../linux/files/debian/control.tmpl           | 25 ++++++-
>  .../linux/files/debian/isar/build.tmpl        | 13 +++-
>  .../linux/files/debian/isar/common.tmpl       | 14 +++-
>  .../linux/files/debian/isar/configure.tmpl    | 13 +++-
>  .../linux/files/debian/isar/install.tmpl      | 73 ++++++++++++++-----
>  .../linux/files/debian/rules.tmpl             |  2 +-
>  meta/recipes-kernel/linux/linux-custom.inc    | 51 ++++++++++---
>  11 files changed, 219 insertions(+), 54 deletions(-)

I've recently went on testing the patchset in CI.

- For now, on updated 'next' it at least requires some trivial changes fixups 
caused by merged "getVar(var, True) => getVar(var)" reduction. I could prepare 
v3 on my own or wait for new version on maillist.

- Also, we now have multiarch support patchset merged to `next` (and that is 
the main reason of long non-merging this kbuild patchset). So, even if the 
patch in its current state works, it probably could reuse new approach (e.g. 
<package>-compat or <package>-native).