diff options
| -rw-r--r-- | arch/x86/Kconfig | 4 | ||||
| -rw-r--r-- | arch/x86/Makefile | 5 | ||||
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 10 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 2 | ||||
| -rw-r--r-- | scripts/Makefile.build | 2 |
5 files changed, 10 insertions, 13 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 2af0af33362a..026c2f2ac702 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -440,10 +440,6 @@ config RETPOLINE branches. Requires a compiler with -mindirect-branch=thunk-extern support for full protection. The kernel may run slower. - Without compiler support, at least indirect branches in assembler - code are eliminated. Since this includes the syscall entry path, - it is not entirely pointless. - config INTEL_RDT bool "Intel Resource Director Technology support" default n diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 1c4d012550ec..ce3658dd98e8 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -241,9 +241,10 @@ KBUILD_CFLAGS += -fno-asynchronous-unwind-tables # Avoid indirect branches in kernel to deal with Spectre ifdef CONFIG_RETPOLINE -ifneq ($(RETPOLINE_CFLAGS),) - KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) -DRETPOLINE +ifeq ($(RETPOLINE_CFLAGS),) + $(error You are building kernel with non-retpoline compiler, please update your compiler.) endif + KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) endif archscripts: scripts_basic diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index 7827f17e9a8a..690c838e3a7e 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -162,11 +162,12 @@ _ASM_PTR " 999b\n\t" \ ".popsection\n\t" -#if defined(CONFIG_X86_64) && defined(RETPOLINE) +#ifdef CONFIG_RETPOLINE +#ifdef CONFIG_X86_64 /* - * Since the inline asm uses the %V modifier which is only in newer GCC, - * the 64-bit one is dependent on RETPOLINE not CONFIG_RETPOLINE. + * Inline asm uses the %V modifier which is only in newer GCC + * which is ensured when CONFIG_RETPOLINE is defined. */ # define CALL_NOSPEC \ ANNOTATE_NOSPEC_ALTERNATIVE \ @@ -181,7 +182,7 @@ X86_FEATURE_RETPOLINE_AMD) # define THUNK_TARGET(addr) [thunk_target] "r" (addr) -#elif defined(CONFIG_X86_32) && defined(CONFIG_RETPOLINE) +#else /* CONFIG_X86_32 */ /* * For i386 we use the original ret-equivalent retpoline, because * otherwise we'll run out of registers. We don't care about CET @@ -211,6 +212,7 @@ X86_FEATURE_RETPOLINE_AMD) # define THUNK_TARGET(addr) [thunk_target] "rm" (addr) +#endif #else /* No retpoline for C / inline asm */ # define CALL_NOSPEC "call *%[thunk_target]\n" # define THUNK_TARGET(addr) [thunk_target] "rm" (addr) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 700d1149601e..a0146ee52124 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -251,7 +251,7 @@ static void __init spec2_print_if_secure(const char *reason) static inline bool retp_compiler(void) { - return __is_defined(RETPOLINE); + return __is_defined(CONFIG_RETPOLINE); } static inline bool match_option(const char *arg, int arglen, const char *opt) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 7143da06d702..be9e5deb58ba 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -272,10 +272,8 @@ else objtool_args += $(call cc-ifversion, -lt, 0405, --no-unreachable) endif ifdef CONFIG_RETPOLINE -ifneq ($(RETPOLINE_CFLAGS),) objtool_args += --retpoline endif -endif ifdef CONFIG_MODVERSIONS |