From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: IPv6 issue in next-20171102 - lockdep and BUG handling RA packet.
Date: Tue, 7 Nov 2017 09:39:08 +0900
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Cc: Valdis Kletnieks <valdis.kletnieks@vt.edu>,
        "David S. Miller" <davem@davemloft.net>,
        LKML <linux-kernel@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>
To: Eric Dumazet <edumazet@google.com>
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On 11/7/17 9:31 AM, Eric Dumazet wrote:
> On Mon, Nov 6, 2017 at 4:29 PM, David Ahern <dsahern@gmail.com> wrote:
>> On 11/7/17 5:56 AM, valdis.kletnieks@vt.edu wrote:
>>> I've hit this 6 times now, across 3 boots:
>>>
>>> Nov  3 11:04:54 turing-police kernel: [  547.814748] BUG: sleeping function called from invalid context at mm/slab.h:422
>>>
>>> Nov  3 20:24:11 turing-police kernel: [   60.093793] BUG: sleeping function called from invalid context at mm/slab.h:422
>>> Nov  4 20:20:54 turing-police kernel: [86264.366955] BUG: sleeping function called from invalid context at mm/slab.h:422
>>> Nov  5 19:17:40 turing-police kernel: [172469.769179] BUG: sleeping function called from invalid context at mm/slab.h:422
>>> Nov  6 06:07:37 turing-police kernel: [211467.239460] BUG: sleeping function called from invalid context at mm/slab.h:422
>>>
>>> Nov  6 14:12:43 turing-police kernel: [   54.891848] BUG: sleeping function called from invalid context at mm/slab.h:422
>>>
>>> Something seems to be going astray while handling a RA packet.
>>
>> Odd. I tested RA before sending the patches and again just now - no
>> traceback with an RCU / lock debugging kernel. What is sending the RA's
>> in your case? I'd like to understand the config and add a test for this.
> 
> Do you have CONFIG_DEBUG_ATOMIC_SLEEP=y in your .config ?
> 

I needed to set sysctl -w net.ipv6.conf.eth1.use_tempaddr=1. With that I
see the trace.