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Date:   Mon, 14 Jan 2019 11:16:57 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Ingo Molnar <mingo@redhat.com>, peterz@infradead.org,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Andrea Righi <righi.andrea@gmail.com>
Subject: Re: [PATCH v2 5/9] kprobes: Search non-suffixed symbol in blacklist
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        <154726008226.18060.9082091974811290044.stgit@devbox>
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On Sat, 12 Jan 2019 11:28:02 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:

> Newer gcc can generate some different instances of a function
> with suffixed symbols if the function is optimized and only
> has a part of that. (e.g. .constprop, .part etc.)
> 
> In this case, it is not enough to check the entry of kprobe
> blacklist because it only records non-suffixed symbol address.
> 
> To fix this issue, search non-suffixed symbol in blacklist if
> given address is within a symbol which has a suffix.
> 
> Note that this can cause false positive cases if a kprobe-safe
> function is optimized to suffixed instance and has same name
> symbol which is blacklisted.
> But I would like to chose a fail-safe design for this issue.
> 
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>

Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

-- Steve