When running selftests from the kernel top-level (e.g. make kselftest-all),
sub-makes might still inherit the caller's PWD from the environment.
Some selftests use $(PWD) in recursive kbuild invocations, which can
then incorrectly resolve to the kernel top directory instead of the
current test directory.
In that case, kbuild may generate an external-module wrapper Makefile in
the wrong location, potentially clobbering the top-level Makefile and
causing recursive include failures ("Too many open files").
Export PWD := $(CURDIR) in selftests/lib.mk so $(PWD) always matches the
actual current selftest directory.
Reported-by: Andrew Morton <[email protected]>
Signed-off-by: Li Wang <[email protected]>
---
tools/testing/selftests/lib.mk | 2 ++
tools/testing/selftests/mm/local_config.stamp | 0
2 files changed, 2 insertions(+)
create mode 100644 tools/testing/selftests/mm/local_config.stamp
diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index f02cc8a2e4ae..2840e98c225c 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -60,6 +60,8 @@ endif
selfdir = $(realpath $(dir $(filter %/lib.mk,$(MAKEFILE_LIST))))
top_srcdir = $(selfdir)/../../..
+export PWD := $(CURDIR)
+
# msg: emit succinct information message describing current building step
# $1 - generic step name (e.g., CC, LINK, etc);
# $2 - optional "flavor" specifier; if provided, will be emitted as [flavor];
diff --git a/tools/testing/selftests/mm/local_config.stamp
b/tools/testing/selftests/mm/local_config.stamp
new file mode 100644
index 000000000000..e69de29bb2d1
--
2.53.0
