Re: [PATCH net 1/2] selftests: netfilter: use KHDR_INCLUDES in CFLAGS

From: Ilya Maximets

Date: Fri Sep 04 2026 - 12:42:05 EST


On 9/4/26 6:13 PM, Matthieu Baerts (NGI0) wrote:
> KHDR_INCLUDES is typically used to include headers from the kernel
> source directory instead of only relying on the ones from the host: they
> can be missing or outdated.
>
> The kselftest doc recommends assigning KHDR_INCLUDES to CFLAGS in a
> target Makefile. lib.mk will set KHDR_INCLUDES to "-isystem
> $(top_srcdir)/usr/include" if the user didn't set it, e.g. if the kernel
> was built in a different build directory.
>
> Other net targets have KHDR_INCLUDES added to their CFLAGS.
>
> Fixes: 3f189349e52a ("selftests: netfilter: move to net subdir")

I think, this should point to a commit that added the first C test:

Fixes: a64d558d8cf9 ("selftests: netfilter: add nfqueue test case")

> Link: https://docs.kernel.org/dev-tools/kselftest.html#contributing-new-tests-details
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
> ---
> tools/testing/selftests/net/netfilter/Makefile | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/tools/testing/selftests/net/netfilter/Makefile b/tools/testing/selftests/net/netfilter/Makefile
> index f88dd4ef8d26..df3c20c90f5d 100644
> --- a/tools/testing/selftests/net/netfilter/Makefile
> +++ b/tools/testing/selftests/net/netfilter/Makefile
> @@ -2,6 +2,8 @@
>
> top_srcdir = ../../../../..
>
> +CFLAGS += $(KHDR_INCLUDES)
> +
> HOSTPKG_CONFIG := pkg-config
> MNL_CFLAGS := $(shell $(HOSTPKG_CONFIG) --cflags libmnl 2>/dev/null)
> MNL_LDLIBS := $(shell $(HOSTPKG_CONFIG) --libs libmnl 2>/dev/null || echo -lmnl)
>

This solves my problem with building netfilter tests locally with uAPI
modifications. Beside the Fixes tag, LGTM.

Reviewed-by: Ilya Maximets <i.maximets@xxxxxxx>