From 22d8b3dec214cd43a773f621f95d254c50d2a092 Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Wed, 19 Apr 2017 18:21:05 +0530 Subject: [PATCH] powerpc/kprobes: Emulate instructions on kprobe handler re-entry On kprobe handler re-entry, try to emulate the instruction rather than single stepping always. Acked-by: Ananth N Mavinakayanahalli Signed-off-by: Naveen N. Rao Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/kprobes.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index ed5a917c2edd..b71922618ed2 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -277,6 +277,14 @@ int __kprobes kprobe_handler(struct pt_regs *regs) kprobes_inc_nmissed_count(p); prepare_singlestep(p, regs); kcb->kprobe_status = KPROBE_REENTER; + if (p->ainsn.boostable >= 0) { + ret = try_to_emulate(p, regs); + + if (ret > 0) { + restore_previous_kprobe(kcb); + return 1; + } + } return 1; } else { if (*addr != BREAKPOINT_INSTRUCTION) { -- 2.20.1