[PATCH 1/4] selftests/mm: remove flaky header check

Kevin Brodsky
2025-12-16T14:26:47Z

Commit 96ed62ea0298 ("mm: page_frag: fix a compile error when kernel
is not compiled") introduced a check to avoid attempting to build
the page_frag module if <linux/page_frag_cache.h> is missing.

Unfortunately this check only works if KDIR points to
/lib/modules/... or an in-tree kernel build. It always fails if KDIR
points to an out-of-tree build (i.e. when the kernel was built with
O=$KDIR make) because only generated headers are present under
$KDIR/include/ in that case.

<linux/page_frag_cache.h> was added more than a year ago (v6.13) so
we can probably live without that check.

Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
---
tools/testing/selftests/mm/Makefile | 4 ----
1 file changed, 4 deletions(-)

diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
index eaf9312097f7..aba51fcac752 100644
--- a/tools/testing/selftests/mm/Makefile
+++ b/tools/testing/selftests/mm/Makefile
@@ -46,12 +46,8 @@ CFLAGS += -U_FORTIFY_SOURCE

KDIR ?= /lib/modules/$(shell uname -r)/build
ifneq (,$(wildcard $(KDIR)/Module.symvers))
-ifneq (,$(wildcard $(KDIR)/include/linux/page_frag_cache.h))
TEST_GEN_MODS_DIR := page_frag
else
-PAGE_FRAG_WARNING = "missing page_frag_cache.h, please use a newer kernel"
-endif
-else
PAGE_FRAG_WARNING = "missing Module.symvers, please have the kernel built first"
endif

--
2.51.2