Re: [PATCH 1/3] powerpc: kprobes: add support for KPROBES_ON_FTRACE
From: Masami Hiramatsu <mhiramat@kernel.org>
Date: 2017-02-15 07:11:33
Also in:
lkml
Subsystem:
kprobes, the rest · Maintainers:
Naveen N Rao, "David S. Miller", Masami Hiramatsu, Linus Torvalds
Hi Naveen, On Wed, 15 Feb 2017 00:28:34 +0530 "Naveen N. Rao" [off-list ref] wrote:
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c index e51a045f3d3b..a8f414a0b141 100644 --- a/arch/powerpc/kernel/optprobes.c +++ b/arch/powerpc/kernel/optprobes.c@@ -70,6 +70,9 @@ static unsigned long can_optimize(struct kprobe *p) struct instruction_op op; unsigned long nip = 0; + if (unlikely(kprobe_ftrace(p))) + return 0; +
Hmm, this should not be checked in arch-depend code, since it may duplicate
code in each arch. Please try below.
Thanks,
commit 897bb304974c1b0c19a4274fea220b175b07f353
Author: Masami Hiramatsu [off-list ref]
Date: Wed Feb 15 15:48:14 2017 +0900
kprobes: Skip preparing optprobe if the probe is ftrace-based
Skip preparing optprobe if the probe is ftrace-based, since
anyway, it must not be optimized (or already optimized by
ftrace).
Signed-off-by: Masami Hiramatsu [off-list ref]
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index ebb4dad..546a8b1 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c@@ -746,13 +746,20 @@ static void kill_optimized_kprobe(struct kprobe *p) arch_remove_optimized_kprobe(op); } +static inline +void __prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p) +{ + if (!kprobe_ftrace(p)) + arch_prepare_optimized_kprobe(op, p); +} + /* Try to prepare optimized instructions */ static void prepare_optimized_kprobe(struct kprobe *p) { struct optimized_kprobe *op; op = container_of(p, struct optimized_kprobe, kp); - arch_prepare_optimized_kprobe(op, p); + __prepare_optimized_kprobe(op, p); } /* Allocate new optimized_kprobe and try to prepare optimized instructions */
@@ -766,7 +773,7 @@ static struct kprobe *alloc_aggr_kprobe(struct kprobe *p) INIT_LIST_HEAD(&op->list); op->kp.addr = p->addr; - arch_prepare_optimized_kprobe(op, p); + __prepare_optimized_kprobe(op, p); return &op->kp; }
--
Masami Hiramatsu <mhiramat@kernel.org>