[PATCH 05/24] x86: Annotate indirect jump in head_64.S

From: Peter Zijlstra
Date: Tue Jan 23 2018 - 10:42:45 EST


The objtool retpoline validation found this indirect jump. Seeing how
its on CPU bringup before we run userspace it should be safe, annotate
it.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/x86/kernel/head_64.S | 2 ++
1 file changed, 2 insertions(+)

--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -23,6 +23,7 @@
#include <asm/nops.h>
#include "../entry/calling.h"
#include <asm/export.h>
+#include <asm/nospec-branch.h>

#ifdef CONFIG_PARAVIRT
#include <asm/asm-offsets.h>
@@ -134,6 +135,7 @@ ENTRY(secondary_startup_64)

/* Ensure I am executing from virtual addresses */
movq $1f, %rax
+ ANNOTATE_RETPOLINE_SAFE
jmp *%rax
1:
UNWIND_HINT_EMPTY