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Date:   Thu, 23 Sep 2021 06:14:17 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc:     netdev@vger.kernel.org, linyunsheng@huawei.com,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Neil Horman <nhorman@redhat.com>,
        Dust Li <dust.li@linux.alibaba.com>,
        Wei Wang <weiwan@google.com>
Subject: Re: [PATCH net v2] napi: fix race inside napi_enable
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On Wed, 22 Sep 2021 14:47:47 +0800 Xuan Zhuo wrote:
> > Why don't you just invert the order of clearing the bits:  
> 
> I think it should be an atomic operation. The original two-step clear itself is
> problematic. So from this perspective, it is not just a solution to this
> problem.

[resending, my MUA seems to have corrupted the CC list previously]

Can you show what breaks by it being non-atomic?

Because, again, the disable part is not atomic. Either it's needed on
both sides or it's not needed on either.