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From:   Song Liu <songliubraving@fb.com>
To:     Steven Rostedt <rostedt@goodmis.org>
CC:     Song Liu <song@kernel.org>, Networking <netdev@vger.kernel.org>,
        bpf <bpf@vger.kernel.org>, lkml <linux-kernel@vger.kernel.org>,
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Subject: Re: [PATCH v2 bpf-next 3/5] ftrace: introduce
 FTRACE_OPS_FL_SHARE_IPMODIFY
Thread-Topic: [PATCH v2 bpf-next 3/5] ftrace: introduce
 FTRACE_OPS_FL_SHARE_IPMODIFY
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Date:   Fri, 15 Jul 2022 02:50:07 +0000
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> On Jul 14, 2022, at 7:46 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> On Fri, 15 Jul 2022 02:04:33 +0000
> Song Liu <songliubraving@fb.com> wrote:
> 
>>> What I'm suggesting is that a DIRECT ops will never set IPMODIFY.  
>> 
>> Aha, this the point I misunderstood. I thought DIRECT ops would always
>> set IPMODIFY (as it does now). 
> 
> My fault. I was probably not being clear when I was suggesting that
> DIRECT should *act* like an IPMODIFY, but never explicitly stated that
> it should not set the IPMODIFY flag.
> 
> The only reason it does today was to make it easy to act like an
> IPMODIFY (because it set the flag). But I'm now suggesting to get rid
> of that and just make DIRECT act like an IPMDOFIY as there can only be
> one of them on a function, but now we have some cases where DIRECT can
> work with IPMODIFY via the callbacks.

Thanks for the clarification. I think we are finally on the same page on
this. :)

Song