On 5/7/25 01:23, Masahiro Yamada wrote:
On Wed, May 7, 2025 at 7:07 AM Shuah Khan skhan@linuxfoundation.org wrote:
On 5/6/25 05:12, Nicolas Schier wrote:
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 skhan@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 \
Would it make sense to check for include/generated as a catch all?
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:
I considered adding a check for not finding include/generated/compile.h and figured if include/config is found we are probably safe.
I will fix that.
I do not think this patch makes sense.
Kbuild correctly detects that "the source tree is not clean enough to build with ARCH=um", and displays the following message:
*** The source tree is not clean, please run 'make ARCH=um mrproper' *** in /linux/linux_srcdir
This is absolutely correct.
It detects it can't build um - but it doesn't detect that the source tree is not clean. The problem is once user runs 'make ARCH=um mrproper' - these checks will find the source tree clean even though it isn't - a subsequent x86_64 build could fail.
If kbuild suggests mrproper for the existing kernel build instead, the source tree will be cleaned correctly.
The real issue is that "make ARCH=um mrproper" does not properly clean the source tree.
The patch you sent doesn't solve the problem I am seeing. You can find the details on the patch thread.
thanks, -- Shuah