From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <cwang@twopensource.com>
Subject: Re: Suspicious RCU usage in bridge with Linux v4.0-9362-g1fc149933fd4
Date: Mon, 4 May 2015 11:45:41 -0700
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To: Dominick Grift <dac.override@gmail.com>
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On Mon, May 4, 2015 at 6:39 AM, Dominick Grift <dac.override@gmail.com> wrote:
> On Thu, Apr 23, 2015 at 01:07:45PM -0400, Josh Boyer wrote:
>> Hi All,
>>
>> We've had a user report the following backtrace from the bridge module
>> with a recent Linus' tree.  Has anything like this been reported yet?
>> If you have any questions on setup, the user is CC'd.
>>
>> josh
>>
>> [   29.382235] br0: port 1(tap0) entered forwarding state
>>
>> [   29.382286] ===============================
>> [   29.382315] [ INFO: suspicious RCU usage. ]
>> [   29.382344] 4.1.0-0.rc0.git11.1.fc23.x86_64 #1 Not tainted
>> [   29.382380] -------------------------------
>> [   29.382409] net/bridge/br_private.h:626 suspicious
>> rcu_dereference_check() usage!
>
> <snip>
>
> With 4.1.0-0.rc1.git1.1.fc23.x86_64 the situation seems to have slightly changed:
>

Should be the same issue. Please give the attached patch a try,
it is compile-tested only.

Thanks!

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