diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index b7217b5251f5..56e360e019ec 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -128,6 +128,11 @@ endef
 clean:
 	$(CLEAN)
 
+# Enables to extend CFLAGS and LDFLAGS from command line, e.g.
+# make USERCFLAGS=-Werror USERLDFLAGS=-static
+CFLAGS += $(USERCFLAGS)
+LDFLAGS += $(USERLDFLAGS)
+
 # When make O= with kselftest target from main level
 # the following aren't defined.
 #