From: Marco Elver <elver@xxxxxxxxxx> Subject: kcov: unconditionally add -fno-stack-protector to compiler options Unconditionally add -fno-stack-protector to KCOV's compiler options, as all supported compilers support the option. This saves a compiler invocation to determine if the option is supported. Because Clang does not support -fno-conserve-stack, and -fno-stack-protector was wrapped in the same cc-option, we were missing -fno-stack-protector with Clang. Unconditionally adding this option fixes this for Clang. Link: http://lkml.kernel.org/r/20200615184302.7591-1-elver@xxxxxxxxxx Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Suggested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/Makefile~kcov-unconditionally-add-fno-stack-protector-to-compiler-options +++ a/kernel/Makefile @@ -36,7 +36,7 @@ KCOV_INSTRUMENT_stacktrace.o := n KCOV_INSTRUMENT_kcov.o := n KASAN_SANITIZE_kcov.o := n KCSAN_SANITIZE_kcov.o := n -CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) +CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector # cond_syscall is currently not LTO compatible CFLAGS_sys_ni.o = $(DISABLE_LTO) _
