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Date:   Wed, 8 Jun 2022 12:08:30 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc:     Jiri Olsa <olsajiri@gmail.com>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Alexei Starovoitov <ast@kernel.org>,
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        Andrii Nakryiko <andrii@kernel.org>,
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        Martin KaFai Lau <kafai@fb.com>,
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        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@chromium.org>,
        Masami Hiramatsu <mhiramat@kernel.org>
Subject: Re: [PATCHv2 bpf 3/3] bpf: Force cookies array to follow symbols
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On Wed, 8 Jun 2022 08:59:50 -0700
Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:

> Would it be possible to preprocess ftrace_pages to remove such invalid
> records (so that by the time we have to report
> available_filter_functions there are no invalid records)? Or that data
> is read-only when kernel is running?

It's possible, but will be time consuming (slow down boot up) and racy. In
other words, I didn't feel it was worth it.

We can add it. How much of an issue is it to have these place holders for
you? Currently, I only see it causes issues with tests. Is it really an
issue for use cases?

-- Steve