On Fri, Oct 08, 2021 at 12:21:12PM +0200, Mickaël Salaün wrote: > > On 07/10/2021 21:48, Kees Cook wrote: > > On Thu, Oct 07, 2021 at 08:23:20PM +0200, Mickaël Salaün wrote: > > [...] > > >> diff --git a/tools/testing/selftests/interpreter/Makefile b/tools/testing/selftests/interpreter/Makefile > >> new file mode 100644 > >> index 000000000000..1f71a161d40b > >> --- /dev/null > >> +++ b/tools/testing/selftests/interpreter/Makefile > >> @@ -0,0 +1,21 @@ > >> +# SPDX-License-Identifier: GPL-2.0 > >> + > >> +CFLAGS += -Wall -O2 > >> +LDLIBS += -lcap > >> + > >> +src_test := $(wildcard *_test.c) > >> +TEST_GEN_PROGS := $(src_test:.c=) > >> + > >> +KSFT_KHDR_INSTALL := 1 > >> +include ../lib.mk > >> + > >> +khdr_dir = $(top_srcdir)/usr/include > >> + > >> +$(khdr_dir)/asm-generic/unistd.h: khdr > >> + @: > >> + > >> +$(khdr_dir)/linux/trusted-for.h: khdr > >> + @: > >> + > >> +$(OUTPUT)/%_test: %_test.c $(khdr_dir)/asm-generic/unistd.h $(khdr_dir)/linux/trusted-for.h ../kselftest_harness.h > >> + $(LINK.c) $< $(LDLIBS) -o $@ -I$(khdr_dir) > > > > Is all this really needed? > > Yes, all this is needed to be sure that the tests will be rebuild when a > dependency change (either one of the header files or a source file). > > > > > - CFLAGS and LDLIBS will be used by the default rules > > Yes, but it will only run the build command when a source file change, > not a header file. > > > - khdr is already a pre-dependency when KSFT_KHDR_INSTALL is set > > Yes, but it is not enough to rebuild the tests (and check the installed > files) when a header file change. > > > - kselftest_harness.h is already a build-dep (see LOCAL_HDRS) > > Yes, but without an explicit requirement, changing kselftest_harness.h > doesn't force a rebuild. > > > - TEST_GEN_PROGS's .c files are already build-deps > > It is not enough to trigger test rebuilds. > > > > > kselftest does, oddly, lack a common -I when KSFT_KHDR_INSTALL is set > > (which likely should get fixed, though separately from here). > > > > I think you just want: > > > > > > src_test := $(wildcard *_test.c) > > TEST_GEN_PROGS := $(src_test:.c=) > > > > KSFT_KHDR_INSTALL := 1 > > include ../lib.mk > > > > CFLAGS += -Wall -O2 -I$(BUILD)/usr/include > > LDLIBS += -lcap > > > > $(OUTPUT)/%_test: $(BUILD)/usr/include/linux/trusted-for.h > > > > > > (untested) > > > Yep, I re-checked and my Makefile is correct. I didn't find a way to > make it lighter while correctly handling dependencies. > I'll just move the -I to CFLAGS. Okay, thanks for double-checking these. I'll try to fix up kselftests to DTRT here. -- Kees Cook