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Subject: Re: Possible tcp regression in 4.14.13..26
To: Timofey Titovets <nefelim4ag@gmail.com>, netdev@vger.kernel.org
References: <CAGqmi77b0HQAX-dg7JKAWEnu+eFtn8GS+5dsj2kO9Xnzcn_tLg@mail.gmail.com>
From: Eric Dumazet <eric.dumazet@gmail.com>
Message-ID: <1a119dc3-7bd8-0446-e545-f2af77d76a63@gmail.com>
Date: Tue, 13 Mar 2018 14:45:04 -0700
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On 03/13/2018 02:41 PM, Timofey Titovets wrote:
> Hi list,
> We currently upgrade our servers from 4.14.13 to 4.14.26
> And get some problems with random kernel oops by:
> [  422.081094] BUG: unable to handle kernel NULL pointer dereference
> at 0000000000000038
> [  422.081254] IP: tcp_push+0x42/0x110
> [  422.081314] PGD 0 P4D 0
> [  422.081364] Oops: 0002 [#1] SMP PTI
> 
> Currently we assume that this caused by:
> net: tcp: close sock if net namespace is exiting
> [ Upstream commit 4ee806d51176ba7b8ff1efd81f271d7252e03a1d ]
> 
> If that can helps we heavy use docker and ceph rbd.
> 
> I will write if we get more info or fix that.
> 
> Thanks.
> 

Can you provide a full stack trace ?