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Date:   Mon, 22 May 2023 21:38:17 -0700
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To:     Ze Gao <zegao2021@gmail.com>, Jiri Olsa <olsajiri@gmail.com>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Hao Luo <haoluo@google.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Song Liu <song@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Yonghong Song <yhs@fb.com>, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
        kafai@fb.com, kpsingh@chromium.org, netdev@vger.kernel.org,
        paulmck@kernel.org, songliubraving@fb.com,
        Ze Gao <zegao@tencent.com>
References: <20220515203653.4039075-1-jolsa@kernel.org>
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From:   Yonghong Song <yhs@meta.com>
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On 5/21/23 7:07 PM, Ze Gao wrote:
> Oops, I missed that. Thanks for pointing that out, which I thought is
> conditional use of rcu_is_watching before.
> 
> One last point, I think we should double check on this
>       "fentry does not filter with !rcu_is_watching"
> as quoted from Yonghong and argue whether it needs
> the same check for fentry as well.

I would suggest that we address rcu_is_watching issue for fentry
only if we do have a reproducible case to show something goes wrong...

> 
> Regards,
> Ze