Re: [PATCH v4] kbuild: add script and target to generate pacman package

[Masahiro Yamada]

On Thu, Jul 11, 2024 at 4:32 AM Thomas Weißschuh <linux@xxxxxxxxxxxxxx> wrote:
>
> pacman is the package manager used by Arch Linux and its derivates.
> Creating native packages from the kernel tree has multiple advantages:
>
> * The package triggers the correct hooks for initramfs generation and
>   bootloader configuration
> * Uninstallation is complete and also invokes the relevant hooks
> * New UAPI headers can be installed without any manual bookkeeping
>
> The PKGBUILD file is a simplified version of the one used for the
> downstream Arch Linux "linux" package.
> Extra steps that should not be necessary for a development kernel have
> been removed and an UAPI header package has been added.
>
> Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> ---
> Changes in v4:
> - Update MRPROPER_FILES
> - Unify shell variable syntax
> - Link to v3: https://lore.kernel.org/r/20240708-kbuild-pacman-pkg-v3-1-885df3cbc740@xxxxxxxxxxxxxx
>
> Changes in v3:
> - Enforce matching architectures for installation
> - Add Reviewed-by and Tested-by from Nathan
> - Link to v2: https://lore.kernel.org/r/20240706-kbuild-pacman-pkg-v2-1-613422a03a7a@xxxxxxxxxxxxxx
>
> Changes in v2:
> - Replace ${MAKE} with $MAKE for consistency with other variables


Personally, I prefer the brace form ${MAKE}, but
indeed, there is no treewide consistency.







> - Use $MAKE for "-s image_name"
> - Avoid permission warnings from build directory
> - Clarify reason for /build symlink removal
> - Install System.map and config
> - Install dtbs where available
> - Allow cross-build through arch=any
> - Sort Contributor/Maintainer chronologically
> - Disable some unneeded makepkg options
> - Use DEPMOD=true for consistency with rpm-package
> - Link to v1: https://lore.kernel.org/r/20240704-kbuild-pacman-pkg-v1-1-ac2f63f5fa7b@xxxxxxxxxxxxxx
> ---
>  .gitignore               |  6 ++++
>  Makefile                 |  2 +-
>  scripts/Makefile.package | 16 ++++++++++
>  scripts/package/PKGBUILD | 83 ++++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 106 insertions(+), 1 deletion(-)
>
> diff --git a/.gitignore b/.gitignore
> index c59dc60ba62e..7902adf4f7f1 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -92,6 +92,12 @@ modules.order
>  #
>  /tar-install/
>
> +#
> +# pacman files (make pacman-pkg)
> +#
> +/PKGBUILD
> +/pacman/
> +
>  #
>  # We don't want to ignore the following even if they are dot-files
>  #
> diff --git a/Makefile b/Makefile
> index b25b5b44af10..79e8dcec6be9 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1497,7 +1497,7 @@ CLEAN_FILES += vmlinux.symvers modules-only.symvers \
>  # Directories & files removed with 'make mrproper'
>  MRPROPER_FILES += include/config include/generated          \
>                   arch/$(SRCARCH)/include/generated .objdiff \
> -                 debian snap tar-install \
> +                 debian snap tar-install PKGBUILD pacman \
>                   .config .config.old .version \
>                   Module.symvers \
>                   certs/signing_key.pem \
> diff --git a/scripts/Makefile.package b/scripts/Makefile.package
> index bf016af8bf8a..a5b5b899d90c 100644
> --- a/scripts/Makefile.package
> +++ b/scripts/Makefile.package
> @@ -141,6 +141,21 @@ snap-pkg:
>         cd $(objtree)/snap && \
>         snapcraft --target-arch=$(UTS_MACHINE)
>
> +# pacman-pkg
> +# ---------------------------------------------------------------------------
> +
> +PHONY += pacman-pkg
> +pacman-pkg:
> +       @ln -srf $(srctree)/scripts/package/PKGBUILD $(objtree)/PKGBUILD



I really hoped to avoid the symlink and

   makepkg -p $(srctree)/scripts/package/PKGBUILD

would work instead.


However, I got this error.

  makepkg -p /home/masahiro/ref/linux/scripts/package/PKGBUILD
  ==> ERROR: /home/masahiro/ref/linux/scripts/package/PKGBUILD must be
in the current working directory.



So, the -p option does not seem to be useful here.

I hope somebody in the Arch Linux community would consider
supporting PKGBUILD located in a different directory.






> +       cd $(objtree) && \


objtree is always '.'


You are doing "cd . && makepkg"

It is meaningless.



> +               srctree="$(realpath $(srctree))" \

Is this necessary?


> +               objtree="$(realpath $(objtree))" \
> +               BUILDDIR="$(realpath $(objtree))/pacman" \


     BUILDDIR=pacman


> +               CARCH="$(UTS_MACHINE)" \
> +               KBUILD_MAKEFLAGS="$(MAKEFLAGS)" \


Please explain why this is necessary.


With '!makeflags' dropped from options,
it worked for me without MAKEFLAGS/KBUILD_MAKEFLAGS
conversion.


> +               KBUILD_REVISION="$(shell $(srctree)/init/build-version)" \


You are inventing more and more new env variables.

How about this?

   pkgrel="$(${srctree}/init/build-version)"



> +               makepkg
> +
>  # dir-pkg tar*-pkg - tarball targets
>  # ---------------------------------------------------------------------------
>
> @@ -221,6 +236,7 @@ help:
>         @echo '  bindeb-pkg          - Build only the binary kernel deb package'
>         @echo '  snap-pkg            - Build only the binary kernel snap package'
>         @echo '                        (will connect to external hosts)'
> +       @echo '  pacman-pkg          - Build only the binary kernel pacman package'
>         @echo '  dir-pkg             - Build the kernel as a plain directory structure'
>         @echo '  tar-pkg             - Build the kernel as an uncompressed tarball'
>         @echo '  targz-pkg           - Build the kernel as a gzip compressed tarball'
> diff --git a/scripts/package/PKGBUILD b/scripts/package/PKGBUILD
> new file mode 100644
> index 000000000000..b0b133ac28eb
> --- /dev/null
> +++ b/scripts/package/PKGBUILD
> @@ -0,0 +1,83 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +# Maintainer: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> +# Contributor: Jan Alexander Steffens (heftig) <heftig@xxxxxxxxxxxxx>
> +
> +pkgbase=linux-upstream
> +pkgname=("$pkgbase" "$pkgbase-headers" "$pkgbase-api-headers")
> +pkgver="${KERNELRELEASE//-/_}"
> +pkgrel="$KBUILD_REVISION"
> +pkgdesc='Linux'
> +url='https://www.kernel.org/'
> +arch=($CARCH)
> +options=(!debug !strip !buildflags !makeflags)
> +license=(GPL-2.0-only)


makedepends=(
     ...
)

is missing. Is it intentional?




> +build() {
> +  export MAKEFLAGS="$KBUILD_MAKEFLAGS"
> +  cd "$objtree"
> +
> +  # makepkg does a "chmod a-srw", triggering warnings during kbuild
> +  chmod 0755 "$pkgdirbase" || true
> +
> +  $MAKE -f "$srctree/Makefile"

The -f option is unneeded.

Just simply:

      ${MAKE}





> +}
> +
> +package_linux-upstream() {
> +  pkgdesc="The $pkgdesc kernel and modules"
> +
> +  export MAKEFLAGS="$KBUILD_MAKEFLAGS"
> +  cd "$objtree"
> +  local modulesdir="$pkgdir/usr/$MODLIB"
> +
> +  echo "Installing boot image..."
> +  # systemd expects to find the kernel here to allow hibernation
> +  # https://github.com/systemd/systemd/commit/edda44605f06a41fb86b7ab8128dcf99161d2344
> +  install -Dm644 "$($MAKE -s image_name)" "$modulesdir/vmlinuz"
> +
> +  # Used by mkinitcpio to name the kernel
> +  echo "$pkgbase" | install -Dm644 /dev/stdin "$modulesdir/pkgbase"
> +
> +  echo "Installing modules..."
> +  $MAKE INSTALL_MOD_PATH="$pkgdir/usr" INSTALL_MOD_STRIP=1 \
> +    DEPMOD=true modules_install
> +
> +  if $MAKE run-command KBUILD_RUN_COMMAND='test -d $srctree/arch/$SRCARCH/boot/dts' 2>/dev/null; then
> +    echo "Installing dtbs..."
> +    $MAKE INSTALL_DTBS_PATH="$modulesdir/dtb" dtbs_install
> +  fi
> +
> +  # remove build link, will be part of -headers package
> +  rm -f "$modulesdir/build"
> +}
> +
> +package_linux-upstream-headers() {
> +  pkgdesc="Headers and scripts for building modules for the $pkgdesc kernel"
> +
> +  export MAKEFLAGS="$KBUILD_MAKEFLAGS"
> +  cd "$objtree"
> +  local builddir="$pkgdir/usr/$MODLIB/build"
> +
> +  echo "Installing build files..."
> +  "$srctree/scripts/package/install-extmod-build" "$builddir"
> +
> +  echo "Installing System.map and config..."
> +  cp System.map "$builddir/System.map"
> +  cp .config "$builddir/.config"
> +
> +  echo "Adding symlink..."
> +  mkdir -p "$pkgdir/usr/src"
> +  ln -sr "$builddir" "$pkgdir/usr/src/$pkgbase"
> +}
> +
> +package_linux-upstream-api-headers() {
> +  pkgdesc="Kernel headers sanitized for use in userspace"
> +  provides=(linux-api-headers)
> +  conflicts=(linux-api-headers)
> +
> +  export MAKEFLAGS="$KBUILD_MAKEFLAGS"
> +  cd "$objtree"
> +
> +  $MAKE headers_install INSTALL_HDR_PATH="$pkgdir/usr"
> +}
> +
> +# vim:set ts=8 sts=2 sw=2 et:



Documentation/process/coding-style.rst
discourages this.


 """
        /* vim:set sw=8 noet */

 Do not include any of these in source files.
 """




If you need to specify this in .editorconfig



I do not know the style guide of PKGCONFIG.
Does it conventionally use 2-space indentation?






--
Best Regards
Masahiro Yamada