Re: [PATCH v2 1/3] kprobes/x86: use instruction_pointer and instruction_pointer_set

From: Jisheng Zhang
Date: Tue Aug 20 2019 - 05:20:55 EST


On Tue, 20 Aug 2019 09:02:59 +0000 Jisheng Zhang wrote:


>
>
> Hi Thomas,
>
> On Tue, 20 Aug 2019 10:53:58 +0200 (CEST) Thomas Gleixner wrote:
>
> >
> >
> > On Tue, 20 Aug 2019, Jisheng Zhang wrote:
> >
> > > This is to make the x86 kprobe_ftrace_handler() more common so that
> > > the code could be reused in future.
> >
> > While I agree with the change in general, I can't find anything which
> > reuses that code. So the change log is pretty useless and I have no idea
> > how this is related to the rest of the series.

Indeed, this isn't related to the rest of the series. So will update the
change log and resend it alone.

>
> In v1, this code is moved from x86 to common kprobes.c [1]
> But I agree with Masami, consolidation could be done when arm64 kprobes
> on ftrace is stable.
>
> In v2, actually, the arm64 version's kprobe_ftrace_handler() is the same
> as x86's, the only difference is comment, e.g
>
> /* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */
>
> while in arm64
>
> /* Kprobe handler expects regs->pc = ip + 1 as breakpoint hit */
>
>
> W/ above, any suggestion about the suitable change log?
>
> Thanks
>