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Subject: Re: [PATCH]net:sched:release lock before tcf_dump_walker() normal
 return to avoid deadlock
To: Feng Deng <cxdx2006@gmail.com>,
        "David S. Miller" <davem@davemloft.net>
References: <CAEX1niWim7BSki6uRtihwbJ3Adw4Qwt8MR1aki8UA4_x7V9UTA@mail.gmail.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        feng.deng@cortina-access.com, Roman Mashak <mrv@mojatatu.com>,
        Cong Wang <xiyou.wangcong@gmail.com>
From: Jamal Hadi Salim <jhs@mojatatu.com>
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Date: Tue, 6 Dec 2016 08:50:18 -0500
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On 16-12-06 12:36 AM, Feng Deng wrote:
> From: Feng Deng<cxdx2006@gmail.com>
>
> release lock before tcf_dump_walker() normal return to avoid deadlock
>

/Scratching my head.

I am probably missing something obvious.
What are the condition under which this deadlock will happen?
Do you have a testcase we can try?

cheers,
jamal