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Subject[PATCH 17/21] x86/acpi: Convert indirect jump to retpoline
Date
It's kernel policy to not have (unannotated) indirect jumps because of
Spectre v2. This one's probably harmless, but better safe than sorry.
Convert it to a retpoline.

Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
---
arch/x86/kernel/acpi/wakeup_64.S | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S
index 5d3a0b8fd379..0b371580e620 100644
--- a/arch/x86/kernel/acpi/wakeup_64.S
+++ b/arch/x86/kernel/acpi/wakeup_64.S
@@ -7,6 +7,7 @@
#include <asm/msr.h>
#include <asm/asm-offsets.h>
#include <asm/frame.h>
+#include <asm/nospec-branch.h>

# Copyright 2003 Pavel Machek <pavel@suse.cz

@@ -39,7 +40,7 @@ SYM_FUNC_START(wakeup_long64)
movq saved_rbp, %rbp

movq saved_rip, %rax
- jmp *%rax
+ JMP_NOSPEC rax
SYM_FUNC_END(wakeup_long64)

SYM_FUNC_START(do_suspend_lowlevel)
--
2.29.2
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