From: Masahiro Yamada masahiroy@kernel.org
[ Upstream commit ab09da75700e9d25c7dfbc7f7934920beb5e39b9 ]
Building the kernel with O= is affected by stale in-tree build artifacts.
So, if the source tree is not clean, Kbuild displays the following:
$ make ARCH=um O=build defconfig make[1]: Entering directory '/.../linux/build' *** *** The source tree is not clean, please run 'make ARCH=um mrproper' *** in /.../linux *** make[2]: *** [/.../linux/Makefile:673: outputmakefile] Error 1 make[1]: *** [/.../linux/Makefile:248: __sub-make] Error 2 make[1]: Leaving directory '/.../linux/build' make: *** [Makefile:248: __sub-make] Error 2
Usually, running 'make mrproper' is sufficient for cleaning the source tree for out-of-tree builds.
However, building UML generates build artifacts not only in arch/um/, but also in the SUBARCH directory (i.e., arch/x86/). If in-tree stale files remain under arch/x86/, Kbuild will reuse them instead of creating new ones under the specified build directory.
This commit makes 'make ARCH=um clean' recurse into the SUBARCH directory.
Reported-by: Shuah Khan skhan@linuxfoundation.org Closes: https://lore.kernel.org/lkml/20250502172459.14175-1-skhan@linuxfoundation.or... Signed-off-by: Masahiro Yamada masahiroy@kernel.org Acked-by: Johannes Berg johannes@sipsolutions.net Reviewed-by: David Gow davidgow@google.com Reviewed-by: Shuah Khan skhan@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- arch/um/Makefile | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/um/Makefile b/arch/um/Makefile index 94cea8d46b222..daec900ed4631 100644 --- a/arch/um/Makefile +++ b/arch/um/Makefile @@ -154,5 +154,6 @@ MRPROPER_DIRS += arch/$(SUBARCH)/include/generated archclean: @find . ( -name '*.bb' -o -name '*.bbg' -o -name '*.da' \ -o -name '*.gcov' ) -type f -print | xargs rm -f + $(Q)$(MAKE) -f $(srctree)/Makefile ARCH=$(HEADER_ARCH) clean
export HEADER_ARCH SUBARCH USER_CFLAGS CFLAGS_NO_HARDENING OS DEV_NULL_PATH