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Date:   Wed, 23 Mar 2022 13:34:54 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        Jiri Olsa <jolsa@kernel.org>,
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        Steven Rostedt <rostedt@goodmis.org>,
        "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>,
        Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
        "David S . Miller" <davem@davemloft.net>
Subject: Re: [PATCH v13 bpf-next 1/1] rethook: x86: Add rethook x86
 implementation
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On Wed, Mar 23, 2022 at 08:41:19PM +0900, Masami Hiramatsu wrote:

> > Also, what's rethook for anyway?
> 
> Rethook is a feature which hooks the function return. Most of the
> logic came from the kretprobe. Simply to say, 'kretprobe - kprobe' is 
> the rethook :)

I got that far, but why did you take the bother to do these patches? Why
wasn't 'use kretprobe' a good enough option?