On Fri, 02 May 2025, Shuah Khan wrote:
> When make finds the source tree unclean, it prints a message to run
> "make ARCH=x86_64 mrproper" message using the ARCH from the command
> line. The ARCH specified in the command line could be different from
> the ARCH of the existing build in the source tree.
>
> This could cause problems in regular kernel build and kunit workflows.
>
> Regular workflow:
>
> - Build x86_64 kernel
> $ make ARCH=x86_64
> - Try building another arch kernel out of tree with O=
> $ make ARCH=um O=/linux/build
> - kbuild detects source tree is unclean
>
> ***
> *** The source tree is not clean, please run 'make ARCH=um mrproper'
> *** in /linux/linux_srcdir
> ***
>
> - Clean source tree as suggested by kbuild
> $ make ARCH=um mrproper
> - Source clean appears to be clean, but it leaves behind generated header
> files under arch/x86
> arch/x86/realmode/rm/pasyms.h
>
> A subsequent x86_64e build fails with
> "undefined symbol sev_es_trampoline_start referenced ..."
>
> kunit workflow runs into this issue:
>
> - Build x86_64 kernel
> - Run kunit tests: it tries to build for user specified ARCH or uml
> as default:
> $ ./tools/testing/kunit/kunit.py run
>
> - kbuild detects unclean source tree
>
> ***
> *** The source tree is not clean, please run 'make ARCH=um mrproper'
> *** in /linux/linux_6.15
> ***
>
> - Clean source tree as suggested by kbuild
> $ make ARCH=um mrproper
> - Source clean appears to be clean, but it leaves behind generated header
> files under arch/x86
>
> The problem shows when user tries to run tests on ARCH=x86_64:
>
> $ ./tools/testing/kunit/kunit.py run ARCH=x86_64
>
> "undefined symbol sev_es_trampoline_start referenced ..."
>
> Build trips on arch/x86/realmode/rm/pasyms.h left behind by a prior
> x86_64 build.
>
> Problems related to partially cleaned source tree are hard to debug.
> Change Makefile to unclean source logic to use ARCH from compile.h
> UTS_MACHINE string. With this change kbuild prints:
>
> $ ./tools/testing/kunit/kunit.py run
>
> ***
> *** The source tree is not clean, please run 'make ARCH=x86_64 mrproper'
> *** in /linux/linux_6.15
> ***
>
> Signed-off-by: Shuah Khan <sk...@linuxfoundation.org>
> ---
> Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/Makefile b/Makefile
> index 5aa9ee52a765..7ee29136b4da 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -674,7 +674,7 @@ ifeq ($(KBUILD_EXTMOD),)
> -d $(srctree)/include/config -o \
> -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
> echo >&2 "***"; \
> - echo >&2 "*** The source tree is not clean, please run
> 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH))
> mrproper'"; \
> + echo >&2 "*** The source tree is not clean, please run 'make
> ARCH=$(shell grep UTS_MACHINE $(srctree)/include/generated/compile.h | cut -d
> '"' -f 2) mrproper'"; \
Please 'grep' option '-s'.
There are some (rare) occassions, when there is no include/generated/compile.h
but still the source tree will be considered to be dirty:
grep: ../include/generated/compile.h: No such file or directory
***
*** The source tree is not clean, please run 'make ARCH= mrproper'
...
Kind regards,
Nicolas
