From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: [PATCH v2 net-next] tcp: Check daddr_cache before use in
 tracepoint
Date: Wed, 18 Oct 2017 08:54:10 -0600
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 <20171018.141540.2101290573491932828.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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On 10/18/17 7:15 AM, David Miller wrote:
> From: David Ahern <dsahern@gmail.com>
> Date: Mon, 16 Oct 2017 15:32:07 -0700
> 
>> Running perf in one window to capture tcp_retransmit_skb tracepoint:
>>     $ perf record -e tcp:tcp_retransmit_skb -a
>>
>> And causing a retransmission on an active TCP session (e.g., dropping
>> packets in the receiver, changing MTU on the interface to 500 and back
>> to 1500) triggers a panic:
>  ...
>> Check that daddr_cache is non-NULL before de-referencing.
>>
>> Fixes: e086101b150a ("tcp: add a tracepoint for tcp retransmission")
>> Signed-off-by: David Ahern <dsahern@gmail.com>
> 
> Applied.
> 

Hi Dave: There was a v3 to this one. I'll send a diff patch.