On 2023-01-17 04:06, Ingo Molnar wrote:
* Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> wrote:
On 1/16/23 13:18, Mathieu Desnoyers wrote:
On 2023-01-16 14:40, kernel test robot wrote:
tree: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/core
head: 79ba1e607d68178db7d3fe4f6a4aa38f06805e7b
commit: 03f5c0272d1b59343144e199becc911dae52c37e [7/28] selftests/rseq: Use ELF auxiliary vector for extensible rseq
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
reproduce:
# https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=03f5c0272d1b59343144e199becc911dae52c37e
git remote add tip https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
git fetch --no-tags tip sched/core
git checkout 03f5c0272d1b59343144e199becc911dae52c37e
make O=/tmp/kselftest headers
make O=/tmp/kselftest -C tools/testing/selftests
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
In order to fix this, I need to change -I../../../../usr/include/ for $(KHDR_INCLUDES) in tools/testing/selftests/rseq/Makefile
I can find 25 odd uses of the same pattern in the kernel selftests. Should I fix them all in one go ?
kselftest build depends on headers installed in the root directory.
By "root directory", do you mean kernel sources root directory or build
output root directory ?
The main makefile enforces this dependency.
How ? I figure that tools/testing/selftests/lib.mk overrides
KHDR_INCLUDES if it is not defined yet:
ifeq ($(KHDR_INCLUDES),)
KHDR_INCLUDES := -isystem $(top_srcdir)/usr/include
endif
and selftests makefiles include ../lib.mk.
This KHDR_INCLUDES can be modified by O=... when built from the kernel
top level, thus using tools/testing/selftests/Makefile:
ifneq ($(KBUILD_OUTPUT),)
[...]
KHDR_INCLUDES := -isystem ${abs_objtree}/usr/include
else
[...]
KHDR_INCLUDES := -isystem ${abs_srctree}/usr/include
endif
But it's up to the individual selftests to actually use
$(KHDR_INCLUDES). In many cases, they hardcode
-I../../../../usr/include/ which is bogus when the build root (O=...)
differs from the source root.
If this test is being
built without installing headers by itself, I think the scripts that
build individual tests have to makes sure headers are installed first.
The headers were previously built by "make O=/tmp/kselftest headers", as
it should, it's just that the selftest makefile uses a hardcoded path
that is relative to the source directory, and it appears that this
pattern is repeated all across the selftests.
Why isn't the Makefile saying anything about it & enforcing it? self-tests
are usually self-sufficient to build in the individual directories.
In an ideal world, we'd have a way to _remove_ the build environment
kernel headers from the include search paths, because this is a problem
for reproducibility of the tests.
Thanks,
Mathieu
Thanks,
Ingo
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
