From: Andi Kleen <a...@linux.intel.com>

Convert all indirect jumps in ftrace assembler code to use
non speculative sequences.

Based on code from David Woodhouse and Tim Chen

Signed-off-by: Andi Kleen <a...@linux.intel.com>
---
 arch/x86/kernel/ftrace_32.S | 3 ++-
 arch/x86/kernel/ftrace_64.S | 6 +++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/ftrace_32.S b/arch/x86/kernel/ftrace_32.S
index b6c6468e10bc..c0c10ba53375 100644
--- a/arch/x86/kernel/ftrace_32.S
+++ b/arch/x86/kernel/ftrace_32.S
@@ -8,6 +8,7 @@
 #include <asm/segment.h>
 #include <asm/export.h>
 #include <asm/ftrace.h>
+#include <asm/jump-asm.h>
 
 #ifdef CC_USING_FENTRY
 # define function_hook __fentry__
@@ -241,5 +242,5 @@ return_to_handler:
        movl    %eax, %ecx
        popl    %edx
        popl    %eax
-       jmp     *%ecx
+       NOSPEC_JMP      %ecx
 #endif
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S
index c832291d948a..4814c4b30b8d 100644
--- a/arch/x86/kernel/ftrace_64.S
+++ b/arch/x86/kernel/ftrace_64.S
@@ -7,7 +7,7 @@
 #include <asm/ptrace.h>
 #include <asm/ftrace.h>
 #include <asm/export.h>
-
+#include <asm/jump-asm.h>
 
        .code64
        .section .entry.text, "ax"
@@ -286,7 +286,7 @@ trace:
         * ip and parent ip are used and the list function is called when
         * function tracing is enabled.
         */
-       call   *ftrace_trace_function
+       NOSPEC_CALL ftrace_trace_function
 
        restore_mcount_regs
 
@@ -329,5 +329,5 @@ GLOBAL(return_to_handler)
        movq 8(%rsp), %rdx
        movq (%rsp), %rax
        addq $24, %rsp
-       jmp *%rdi
+       NOSPEC_JMP %rdi
 #endif
-- 
2.14.3

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