4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Masahiro Yamada <yamada.masah...@socionext.com>
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 <mr...@linux.ee>
Tested-by: Meelis Roos <mr...@linux.ee>
Signed-off-by: Masahiro Yamada <yamada.masah...@socionext.com>
Acked-by: Zhenzhong Duan <zhenzhong.d...@oracle.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Zhenzhong Duan <zhenzhong.d...@oracle.com>
Fixes: 4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler
support")
Link:
http://lkml.kernel.org/r/1543991239-18476-1-git-send-email-yamada.masah...@socionext.com
Link: https://lkml.org/lkml/2018/12/4/206
Signed-off-by: Ingo Molnar <mi...@kernel.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
Cc: Gi-Oh Kim <gi-oh....@cloud.ionos.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
arch/x86/Makefile | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -223,9 +223,6 @@ 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 += $(RETPOLINE_CFLAGS)
endif
@@ -303,6 +300,13 @@ ifndef CC_HAVE_ASM_GOTO
@echo Compiler lacks asm-goto support.
@exit 1
endif
+ifdef CONFIG_RETPOLINE
+ifeq ($(RETPOLINE_CFLAGS),)
+ @echo "You are building kernel with non-retpoline compiler." >&2
+ @echo "Please update your compiler." >&2
+ @false
+endif
+endif
archclean:
$(Q)rm -rf $(objtree)/arch/i386
