On Thu, 26 Jul 2018 09:41:06 +0900 Masami Hiramatsu <mhira...@kernel.org> wrote:
> On Fri, 13 Jul 2018 08:18:03 -0400 > Steven Rostedt <rost...@goodmis.org> wrote: > > > On Fri, 13 Jul 2018 11:53:01 +0900 > > Masami Hiramatsu <mhira...@kernel.org> wrote: > > > > > On Thu, 12 Jul 2018 13:54:12 -0400 > > > Francis Deslauriers <francis.deslauri...@efficios.com> wrote: > > > > > > > From: Masami Hiramatsu <mhira...@kernel.org> > > > > > > > > Prohibit kprobe-events probing on notrace function. > > > > Since probing on the notrace function can cause recursive > > > > event call. In most case those are just skipped, but > > > > in some case it falls into infinite recursive call. > > > > > > BTW, I'm considering to add an option to allow putting > > > kprobes on notrace function - just for debugging > > > ftrace by kprobes. That is "developer only" option > > > so generally it should be disabled, but for debugging > > > the ftrace, we still need it. Or should I introduce > > > another kprobes module for debugging it? > > > > No, I think the former is better (to add an option to allow putting > > kprobes on notrace functions). By default we let people protect > > themselves. But if then provide a switch that lets you do things that > > might let you shoot yourself in the foot. > > I'm adding CONFIG_KPROBE_EVENTS_ON_NOTRACE kconfig which allows > kprobes on notrace function. I think we don't need to make it > online switchable, since it is only good for ftrace developers. > Works for me. Thanks! -- Steve