WARNING: Use of EXTRA_CFLAGS is deprecated, please use `ccflags-y instead. #31: FILE: Makefile.kbuild:31: +EXTRA_CFLAGS += -DSOURCE_VERSION=\"$(REVISION)\" total: 0 errors, 1 warnings, 0 checks, 53 lines checked Makefile.kbuild has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS.