From 856f96c1455d5c69bfc5f444e358ca0431886dcb Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Nov 2022 15:35:48 +0800 Subject: [PATCH] x86: Use -mindirect-branch-cs-prefix for RETPOLINE builds stable inclusion from stable-v5.10.133 commit 6849ed81a33ae616bfadf40e5c68af265d106dff category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5YVKO Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6849ed81a33ae616bfadf40e5c68af265d106dff -------------------------------- commit 68cf4f2a72ef8786e6b7af6fd9a89f27ac0f520d upstream. In order to further enable commit: bbe2df3f6b6d ("x86/alternative: Try inline spectre_v2=retpoline,amd") add the new GCC flag -mindirect-branch-cs-prefix: https://gcc.gnu.org/g:2196a681d7810ad8b227bf983f38ba716620545e https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102952 https://bugs.llvm.org/show_bug.cgi?id=52323 to RETPOLINE=y builds. This should allow fully inlining retpoline,amd for GCC builds. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Reviewed-by: Kees Cook Acked-by: Nick Desaulniers Link: https://lkml.kernel.org/r/20211119165630.276205624@infradead.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Zheng Zengkai Acked-by: Xie XiuQi --- Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/Makefile b/Makefile index 3cc1aaed9644..47377bdc2656 100644 --- a/Makefile +++ b/Makefile @@ -672,6 +672,7 @@ endif ifdef CONFIG_CC_IS_GCC RETPOLINE_CFLAGS := $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register) +RETPOLINE_CFLAGS += $(call cc-option,-mindirect-branch-cs-prefix) RETPOLINE_VDSO_CFLAGS := $(call cc-option,-mindirect-branch=thunk-inline -mindirect-branch-register) endif ifdef CONFIG_CC_IS_CLANG -- GitLab