From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <xiyou.wangcong@gmail.com>
Subject: Re: [Patch net 00/15] net_sched: remove RCU callbacks from TC
Date: Wed, 25 Oct 2017 13:46:57 -0700
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Cc: Linux Kernel Network Developers <netdev@vger.kernel.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Chris Mi <chrism@mellanox.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Mon, Oct 23, 2017 at 4:31 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
> I did not pretend to give a bug fix, I simply said your patch series was
> probably not the right way.

Generally I agree with you on avoid synchronize_rcu(), but this case
is very special, you need to consider case by case, not just talking
generally.


>
> Sure, we could add back BKL and solve a lot of lockdep issues.
>
>

For the record, this case is about race conditions which lead to
real bugs, not merely lockdep warnings.