From: Marco Elver Date: Tue, 30 Nov 2021 11:44:14 +0000 (+0100) Subject: kcsan, kbuild: Add option for barrier instrumentation only X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=48c9e28e1e249c97bcbf68451947649c55b8c09e;p=linux.git kcsan, kbuild: Add option for barrier instrumentation only Source files that disable KCSAN via KCSAN_SANITIZE := n, remove all instrumentation, including explicit barrier instrumentation. With instrumentation for memory barriers, in few places it is required to enable just the explicit instrumentation for memory barriers to avoid false positives. Providing the Makefile variable KCSAN_INSTRUMENT_BARRIERS_obj.o or KCSAN_INSTRUMENT_BARRIERS (for all files) set to 'y' only enables the explicit barrier instrumentation. Signed-off-by: Marco Elver Signed-off-by: Paul E. McKenney --- diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index d1f865b8c0cba..ab17f7b2e33c4 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -182,6 +182,11 @@ ifeq ($(CONFIG_KCSAN),y) _c_flags += $(if $(patsubst n%,, \ $(KCSAN_SANITIZE_$(basetarget).o)$(KCSAN_SANITIZE)y), \ $(CFLAGS_KCSAN)) +# Some uninstrumented files provide implied barriers required to avoid false +# positives: set KCSAN_INSTRUMENT_BARRIERS for barrier instrumentation only. +_c_flags += $(if $(patsubst n%,, \ + $(KCSAN_INSTRUMENT_BARRIERS_$(basetarget).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \ + -D__KCSAN_INSTRUMENT_BARRIERS__) endif # $(srctree)/$(src) for including checkin headers from generated source files