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Subject: Re: [PATCH] Revert "net: get rid of an signed integer overflow in
 ip_idents_reserve()"
To:     Shaokun Zhang <zhangshaokun@hisilicon.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     Yang Guo <guoyang2@huawei.com>,
        "David S. Miller" <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        Jiri Pirko <jiri@resnulli.us>
References: <1564132635-57634-1-git-send-email-zhangshaokun@hisilicon.com>
From:   Eric Dumazet <eric.dumazet@gmail.com>
Message-ID: <afa992f6-eb5e-8104-9a03-f992b184a6b6@gmail.com>
Date:   Fri, 26 Jul 2019 11:58:29 +0200
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On 7/26/19 11:17 AM, Shaokun Zhang wrote:
> From: Yang Guo <guoyang2@huawei.com>
> 
> There is an significant performance regression with the following
> commit-id <adb03115f459>
> ("net: get rid of an signed integer overflow in ip_idents_reserve()").
> 
>

So, you jump around and took ownership of this issue, while some of us
are already working on it ?

Have you first checked that current UBSAN versions will not complain anymore ?

A revert adding back the original issue would be silly, performance of
benchmarks is nice but secondary.