[PATCH 1/4] kbuild: rpm-pkg: fix build error when _arch is undefined

From: Masahiro Yamada
Date: Thu Jul 14 2022 - 01:08:03 EST

Cross-building (bin)rpm-pkg fails on several architectures.

For example, 'make ARCH=arm binrpm-pkg' fails like follows:

sh ./scripts/package/mkspec prebuilt > ./binkernel.spec
rpmbuild --define "_builddir ." --target \
arm -bb ./binkernel.spec
Building target platforms: arm
Building for target arm
warning: line 19: It's not recommended to have unversioned Obsoletes: Obsoletes: kernel-headers
Executing(%install): /bin/sh -e /var/tmp/rpm-tmp.0S8t2F
+ umask 022
+ cd .
+ mkdir -p /home/masahiro/rpmbuild/BUILDROOT/kernel-5.19.0_rc6-19.%{_arch}/boot
+ make -f ./Makefile image_name
+ cp arch/arm/boot/zImage /home/masahiro/rpmbuild/BUILDROOT/kernel-5.19.0_rc6-19.%{_arch}/boot/vmlinuz-5.19.0-rc6
+ make -f ./Makefile INSTALL_MOD_PATH=/home/masahiro/rpmbuild/BUILDROOT/kernel-5.19.0_rc6-19.%{_arch} modules_install
make[3]: *** No rule to make target '/home/masahiro/rpmbuild/BUILDROOT/kernel-5.19.0_rc6-19.arch/arm/crypto/aes-arm-bs.ko{_arch}/lib/modules/5.19.0-rc6/kernel/%', needed by '__modinst'. Stop.
make[2]: *** [Makefile:1768: modules_install] Error 2
error: Bad exit status from /var/tmp/rpm-tmp.0S8t2F (%install)

By default, 'buildroot' contains %{_arch} (see /usr/lib/rpm/macros).

_arch is generally defined in /usr/lib/rpm/platforms/*/macros, where
the platform sub-directory is specified by --target= option for cross

If the given arch does not exist, %{_arch} is not expanded.
In the example above, --target=arm is passed to rpmbuild, but
/usr/lib/rpm/platforms/arm-linux/ does not exist.

The '%' character in the path confuses GNU make and rpmbuild.

The same occurs for such architectures as csky, microblaze, nios2, etc.

Define _arch if it has not been defined.

Reported-by: Jason Self <jason@xxxxxxxxxxxx>
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>

scripts/package/mkspec | 3 +++
1 file changed, 3 insertions(+)

diff --git a/scripts/package/mkspec b/scripts/package/mkspec
index 7c477ca7dc98..8fa7c5b8a1a1 100755
--- a/scripts/package/mkspec
+++ b/scripts/package/mkspec
@@ -49,6 +49,9 @@ sed -e '/^DEL/d' -e 's/^\t*//' <<EOF
URL: https://www.kernel.org
$S Source: kernel-$__KERNELRELEASE.tar.gz
Provides: $PROVIDES
+ # $UTS_MACHINE as a fallback of _arch in case
+ # /usr/lib/rpm/platform/*/macros was not included.
+ %define _arch %{?_arch:$UTS_MACHINE}
%define __spec_install_post /usr/lib/rpm/brp-compress || :
%define debug_package %{nil}