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From:   Arvind Sankar <nivedita@alum.mit.edu>
Date:   Fri, 17 Jan 2020 13:38:01 -0500
To:     Eric Dumazet <eric.dumazet@gmail.com>
Cc:     Arvind Sankar <nivedita@alum.mit.edu>,
        Peter Zijlstra <peterz@infradead.org>,
        Shaokun Zhang <zhangshaokun@hisilicon.com>,
        David Miller <davem@davemloft.net>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, jinyuqi@huawei.com,
        kuznet@ms2.inr.ac.ru, yoshfuji@linux-ipv6.org, edumazet@google.com,
        guoyang2@huawei.com, Will Deacon <will@kernel.org>
Subject: Re: [PATCH] net: optimize cmpxchg in ip_idents_reserve
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On Fri, Jan 17, 2020 at 10:16:45AM -0800, Eric Dumazet wrote:
> Wasńt it the case back in 2016 already for linux-4.8 ?
> 
> What will prevent someone to send another report to netdev/lkml ?
> 
>  -fno-strict-overflow support is not a prereq for CONFIG_UBSAN.
> 
> Fact that we kept in lib/ubsan.c and lib/test_ubsan.c code for 
> test_ubsan_add_overflow() and test_ubsan_sub_overflow() is disturbing.
> 

No, it was bumped in 2018 in commit cafa0010cd51 ("Raise the minimum
required gcc version to 4.6"). That raised it from 3.2 -> 4.6.