diff options
author | David Woodhouse <dwmw@amazon.co.uk> | 2018-02-19 11:50:57 +0100 |
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committer | Ingo Molnar <mingo@kernel.org> | 2018-02-20 11:17:58 +0100 |
commit | 87358710c1fb4f1bf96bbe2349975ff9953fc9b2 (patch) | |
tree | e299a6ab64aadb44ffd431ae8342e0ae0b266cba /arch/x86/Makefile | |
parent | x86/speculation: Use IBRS if available before calling into firmware (diff) | |
download | linux-87358710c1fb4f1bf96bbe2349975ff9953fc9b2.tar.xz linux-87358710c1fb4f1bf96bbe2349975ff9953fc9b2.zip |
x86/retpoline: Support retpoline builds with Clang
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arjan.van.de.ven@intel.com
Cc: bp@alien8.de
Cc: dave.hansen@intel.com
Cc: jmattson@google.com
Cc: karahmed@amazon.de
Cc: kvm@vger.kernel.org
Cc: pbonzini@redhat.com
Cc: rkrcmar@redhat.com
Link: http://lkml.kernel.org/r/1519037457-7643-5-git-send-email-dwmw@amazon.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/Makefile')
-rw-r--r-- | arch/x86/Makefile | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile index fad55160dcb9..dbc7d0ed2eaa 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -232,7 +232,10 @@ KBUILD_CFLAGS += -fno-asynchronous-unwind-tables # Avoid indirect branches in kernel to deal with Spectre ifdef CONFIG_RETPOLINE - RETPOLINE_CFLAGS += $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register) + RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register + RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk + + RETPOLINE_CFLAGS += $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG))) ifneq ($(RETPOLINE_CFLAGS),) KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) -DRETPOLINE endif |