Re: [PATCH v3] kbuild: deb-pkg: remove the fakeroot builds support

From: Guillem Jover
Date: Tue Nov 28 2023 - 22:40:13 EST


Hi!

On Wed, 2023-11-29 at 08:53:56 +0900, Masahiro Yamada wrote:
> In 2017, the dpkg suite introduced the rootless builds support with the
> following commits:
>
> - 2436807c87b0 ("dpkg-deb: Add support for rootless builds")
> - fca1bfe84068 ("dpkg-buildpackage: Add support for rootless builds")
>
> This feature is available in the default dpkg on Debian 10 and Ubuntu
> 20.04.
>
> Remove the old method.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---
>
> Changes in v3:
> - Remove DEB_RULES_REQUIRES_ROOT=no again
> (resent in order to clarify which one should be applied)

Thanks, as this variable is supposed to be defined by the build driver
(such as dpkg-buildpackage) that calls debian/rules, as covered in the
rootless-builds.txt spec.

> diff --git a/scripts/Makefile.package b/scripts/Makefile.package
> index 0c3adc48dfe8..a81dfb1f5181 100644
> --- a/scripts/Makefile.package
> +++ b/scripts/Makefile.package
> @@ -109,8 +109,6 @@ debian-orig: linux.tar$(debian-orig-suffix) debian
> cp $< ../$(orig-name); \
> fi
>
> -KBUILD_PKG_ROOTCMD ?= 'fakeroot -u'
> -
> PHONY += deb-pkg srcdeb-pkg bindeb-pkg
>
> deb-pkg: private build-type := source,binary
> @@ -125,7 +123,7 @@ deb-pkg srcdeb-pkg bindeb-pkg:
> $(if $(findstring source, $(build-type)), \
> --unsigned-source --compression=$(KDEB_SOURCE_COMPRESS)) \
> $(if $(findstring binary, $(build-type)), \
> - -R'$(MAKE) -f debian/rules' -j1 -r$(KBUILD_PKG_ROOTCMD) -a$$(cat debian/arch), \
> + -R'$(MAKE) -f debian/rules' -j1 -a$$(cat debian/arch), \

Since dpkg 1.14.7, dpkg-buildpackage uses fakeroot if available, so
regardless of anything else this removal seems safe.

> --no-check-builddeps) \
> $(DPKG_FLAGS))
>
> diff --git a/scripts/package/builddeb b/scripts/package/builddeb
> index d7dd0d04c70c..2fe51e6919da 100755
> --- a/scripts/package/builddeb
> +++ b/scripts/package/builddeb
> @@ -36,19 +36,13 @@ create_package() {
> sh -c "cd '$pdir'; find . -type f ! -path './DEBIAN/*' -printf '%P\0' \
> | xargs -r0 md5sum > DEBIAN/md5sums"
>
> - # Fix ownership and permissions
> - if [ "$DEB_RULES_REQUIRES_ROOT" = "no" ]; then
> - dpkg_deb_opts="--root-owner-group"
> - else
> - chown -R root:root "$pdir"
> - fi
> # a+rX in case we are in a restrictive umask environment like 0077
> # ug-s in case we build in a setuid/setgid directory
> chmod -R go-w,a+rX,ug-s "$pdir"
>
> # Create the package
> dpkg-gencontrol -p$pname -P"$pdir"
> - dpkg-deb $dpkg_deb_opts ${KDEB_COMPRESS:+-Z$KDEB_COMPRESS} --build "$pdir" ..
> + dpkg-deb --root-owner-group ${KDEB_COMPRESS:+-Z$KDEB_COMPRESS} --build "$pdir" ..

If you want to make sure dpkg-deb supports that option, perhaps add
«dpkg (>= 1.19.0)» to the package Build-Depends? If that version seems
old enough to be assumed to be present, then unconditionally using it
seems fine.

> }
>
> install_linux_image () {

Otherwise, the change LGTM.

Thanks,
Guillem