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Date:   Tue, 19 Jul 2022 19:27:15 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Song Liu <songliubraving@fb.com>
Cc:     Song Liu <song@kernel.org>, bpf <bpf@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        "live-patching@vger.kernel.org" <live-patching@vger.kernel.org>,
        "daniel@iogearbox.net" <daniel@iogearbox.net>,
        Kernel Team <Kernel-team@fb.com>,
        "jolsa@kernel.org" <jolsa@kernel.org>
Subject: Re: [PATCH v4 bpf-next 2/4] ftrace: allow IPMODIFY and DIRECT ops
 on the same function
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        <20220718055449.3960512-3-song@kernel.org>
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On Tue, 19 Jul 2022 23:24:35 +0000
Song Liu <songliubraving@fb.com> wrote:

> Actually, we cannot blindly lock direct_mutex here, as 
> register_ftrace_direct() already locks it before calling 
> register_ftrace_function(). We still need the if (IPMODIFY)
> check. 

Let's not play games with this then.

Create a register_ftrace_function_nolock()

and use that for register_ftrace_direct().

Otherwise it's going to be a nightmare to keep track of.

-- Steve