From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 net-next] tcp: Check daddr_cache before use in
 tracepoint
Date: Wed, 18 Oct 2017 14:15:40 +0100 (WEST)
Message-ID: <20171018.141540.2101290573491932828.davem@davemloft.net>
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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.