Re: Detecting kprobes generated code addresses

Masami Hiramatsu
2016-12-25T06:16:11Z

On Sun, 25 Dec 2016 12:13:20 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:

> On Thu, 22 Dec 2016 00:42:19 -0600
> Josh Poimboeuf <jpoimboe@redhat.com> wrote:
>
> > Hi Masami,
> >
> > I would like to make __kernel_text_address() be able to detect whether
> > an address belongs to code which was generated by kprobes. As far as I
> > can tell, that information seems to be in the 'pages' lists of
> > kprobe_insn_slots and kprobe_optinsn_slots. But they seem to be
> > protected by mutexes.
>
> Right. It is currently under mutex because it may kick
> page allocation. But I think it is easy to fix that :)

Hmm, IMHO, it seems that we should add a dummy (auto-generated)
symbol for optprobe trampoline code to kallsyms so that
__kernel_text_address() automatically returns true on it.

Thank you,

--
Masami Hiramatsu <mhiramat@kernel.org>