Re: [PATCH 0/3] linux-custom: Split up binaries from kernel headers to kbuild packages

[Uladzimir Bely <ubely@ilbers.de>]

In mail from среда, 9 ноября 2022 г. 13:32:45 +03 user Koch, Stefan wrote:
> Hi
> 
> This patchset is a set of three patches:
> - Support overwriting configured schroot dir
> - Split up binaries from kernel headers to kbuild packages
> - Update custom_kernel docs for split up of kernel scripts and tools
> 

Just some thoughts regarding schroot path overwriting...

What if `linux-custom` recipe could disable specific components?

I mean, currently we have this feature only for `linux-libc-dev` package, that 
is disabled when "nolibcdev" build profile is selected. If we added similar 
build profiles for other components, we could disable also `linux-$
{KERNEL_NAME_PROVIDED}`, linux-image-{KERNEL_NAME_PROVIDED}, linux-headers-
{KERNEL_NAME_PROVIDED} and `linux-image-${KERNEL_NAME_PROVIDED}-dbg`

Then, we make `linux-mainline` build all except `linux-kbuild` (if we don't 
need cross version). And we could create the similar recipe `linux-kbuild` 
that inherits `linux-custom`, but builds only `linux-kbuild` - with 
ISAR_CROSS_COMPILE="0".

Of course, such an approach breaks the feature "build everything from one 
recipe", but it doesn't require "schroot" workaround and would make build 
process more configurable.

> The main use-case was to swap out the binaries
> from the kernel headers package.
> They will 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, and kbuild packages will be created automatically
> 
> Best regards
> 
> Stefan
> 
> Stefan Koch (3):
>   sbuild: Support overwriting configured schroot dir
>   linux-custom: Split up binaries from kernel headers to kbuild packages
>   docs: Update custom_kernel docs for split up of kernel scripts and
>     tools
> 
>  doc/custom_kernel.md                          |  13 +--
>  meta/classes/sbuild.bbclass                   |   9 +-
>  .../linux/files/debian/control.tmpl           |  18 ++-
>  .../linux/files/debian/isar/build.tmpl        |   9 +-
>  .../linux/files/debian/isar/common.tmpl       |   7 +-
>  .../linux/files/debian/isar/install.tmpl      |  64 +++++++++--
>  .../linux/files/debian/rules.tmpl             |   5 +-
>  meta/recipes-kernel/linux/linux-custom.inc    | 104 ++++++++++++++++--
>  8 files changed, 191 insertions(+), 38 deletions(-)