Re: [PATCH -tip v5 00/10] kprobes: Kprobes jump optimizationsupport

From: Frederic Weisbecker
Date: Mon Nov 23 2009 - 22:20:36 EST


On Tue, Nov 24, 2009 at 03:03:19AM +0100, Frederic Weisbecker wrote:
> On Mon, Nov 23, 2009 at 06:21:16PM -0500, Masami Hiramatsu wrote:
> > When the optimized-kprobe is hit before optimization, its handler
> > changes IP(instruction pointer) to copied code and exits. So, the
> > instructions which were copied to detour buffer are executed on the detour
> > buffer.
>
>
>
> Hm, why is it playing such hybrid game there?
> If I understand well, we have executed int 3, executed the
> handler and we jump back to the detour buffer?
>


I got it, I think. We have instructions to patch. And the above
turn this area into dead code, safe to patch.

But still, stop_machine() seem to make it not necessary anymore.

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