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Subject: Re: [PATCH] Revert "net: get rid of an signed integer overflow in
 ip_idents_reserve()"
To:     Eric Dumazet <eric.dumazet@gmail.com>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <1564132635-57634-1-git-send-email-zhangshaokun@hisilicon.com>
 <afa992f6-eb5e-8104-9a03-f992b184a6b6@gmail.com>
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>,
        Jiri Pirko <jiri@resnulli.us>
From:   Shaokun Zhang <zhangshaokun@hisilicon.com>
Message-ID: <c308f1a8-59b5-fb74-4879-e6f89c4a814a@hisilicon.com>
Date:   Fri, 6 Sep 2019 09:25:26 +0800
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Hi Eric,

On 2019/7/26 17:58, Eric Dumazet wrote:
> 
> 
> 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 ?
> 

Any update about this issue?

Thanks,
Shaokun

> 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.
> 
> 
>