[PATCH] kprobes/x86: use instruction_pointer and instruction_pointer_set

[Jisheng Zhang]

Use an arch-independent way to get/set the instruction pointer, we can
make the x86 kprobe_ftrace_handler() more common.

Signed-off-by: Jisheng Zhang <jisheng.zh...@synaptics.com>
Acked-by: Masami Hiramatsu <mhira...@kernel.org>
---
 arch/x86/kernel/kprobes/ftrace.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/kprobes/ftrace.c b/arch/x86/kernel/kprobes/ftrace.c
index 681a4b36e9bb..c2ad0b9259ca 100644
--- a/arch/x86/kernel/kprobes/ftrace.c
+++ b/arch/x86/kernel/kprobes/ftrace.c
@@ -28,9 +28,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long 
parent_ip,
        if (kprobe_running()) {
                kprobes_inc_nmissed_count(p);
        } else {
-               unsigned long orig_ip = regs->ip;
+               unsigned long orig_ip = instruction_pointer(regs);
                /* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */
-               regs->ip = ip + sizeof(kprobe_opcode_t);
+               instruction_pointer_set(regs, ip + sizeof(kprobe_opcode_t));
 
                __this_cpu_write(current_kprobe, p);
                kcb->kprobe_status = KPROBE_HIT_ACTIVE;
@@ -39,12 +39,13 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long 
parent_ip,
                         * Emulate singlestep (and also recover regs->ip)
                         * as if there is a 5byte nop
                         */
-                       regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
+                       instruction_pointer_set(regs,
+                               (unsigned long)p->addr + MCOUNT_INSN_SIZE);
                        if (unlikely(p->post_handler)) {
                                kcb->kprobe_status = KPROBE_HIT_SSDONE;
                                p->post_handler(p, regs, 0);
                        }
-                       regs->ip = orig_ip;
+                       instruction_pointer_set(regs, orig_ip);
                }
                /*
                 * If pre_handler returns !0, it changes regs->ip. We have to
-- 
2.23.0.rc1