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From:   Justin Capella <justincapella@gmail.com>
Date:   Fri, 3 Jan 2020 00:00:23 -0800
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Subject: Re: [PATCH v2] ftrace: avoid potential division by zero
To:     Wen Yang <wenyang@linux.alibaba.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>, xlpang@linux.alibaba.com,
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> -               do_div(stddev, rec->counter * (rec->counter - 1) * 1000);
>
> +               stddev = div64_ul(stddev,
> +                                 rec->counter * (rec->counter - 1) * 1000);


Is a rec->counter > 1 assertion needed here?