From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] neigh: increase queue_len_bytes to match
 wmem_default
Date: Tue, 29 Aug 2017 16:11:05 -0700 (PDT)
Message-ID: <20170829.161105.2284035808066192697.davem@davemloft.net>
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Cc: f.fainelli@gmail.com, netdev@vger.kernel.org
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 29 Aug 2017 15:16:01 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> Florian reported UDP xmit drops that could be root caused to the
> too small neigh limit.
> 
> Current limit is 64 KB, meaning that even a single UDP socket would hit
> it, since its default sk_sndbuf comes from net.core.wmem_default
> (~212992 bytes on 64bit arches).
> 
> Once ARP/ND resolution is in progress, we should allow a little more
> packets to be queued, at least for one producer.
> 
> Once neigh arp_queue is filled, a rogue socket should hit its sk_sndbuf
> limit and either block in sendmsg() or return -EAGAIN.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Florian Fainelli <f.fainelli@gmail.com>

Applied, thanks for following up on this.