4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Masahiro Yamada <[email protected]> commit 25896d073d8a0403b07e6dec56f58e6c33678207 upstream. It is troublesome to add a diagnostic like this to the Makefile parse stage because the top-level Makefile could be parsed with a stale include/config/auto.conf. Once you are hit by the error about non-retpoline compiler, the compilation still breaks even after disabling CONFIG_RETPOLINE. The easiest fix is to move this check to the "archprepare" like this commit did: 829fe4aa9ac1 ("x86: Allow generating user-space headers without a compiler") Reported-by: Meelis Roos <[email protected]> Tested-by: Meelis Roos <[email protected]> Signed-off-by: Masahiro Yamada <[email protected]> Acked-by: Zhenzhong Duan <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Zhenzhong Duan <[email protected]> Fixes: 4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support") Link: http://lkml.kernel.org/r/[email protected] Link: https://lkml.org/lkml/2018/12/4/206 Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Cc: Gi-Oh Kim <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/Makefile | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -241,9 +241,6 @@ KBUILD_CFLAGS += -fno-asynchronous-unwin # Avoid indirect branches in kernel to deal with Spectre ifdef CONFIG_RETPOLINE -ifeq ($(RETPOLINE_CFLAGS),) - $(error You are building kernel with non-retpoline compiler, please update your compiler.) -endif KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) endif @@ -260,6 +257,13 @@ archprepare: ifeq ($(CONFIG_KEXEC_FILE),y) $(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c endif +ifdef CONFIG_RETPOLINE +ifeq ($(RETPOLINE_CFLAGS),) + @echo "You are building kernel with non-retpoline compiler." >&2 + @echo "Please update your compiler." >&2 + @false +endif +endif ### # Kernel objects
