From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] tcp: clear pfmemalloc on outgoing skb
Date: Fri, 03 Feb 2017 16:24:08 -0500 (EST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 02 Feb 2017 20:40:08 -0800

> From: Eric Dumazet <edumazet@google.com>
> 
> Josef Bacik diagnosed following problem :
> 
>    I was seeing random disconnects while testing NBD over loopback.
>    This turned out to be because NBD sets pfmemalloc on it's socket,
>    however the receiving side is a user space application so does not
>    have pfmemalloc set on its socket. This means that
>    sk_filter_trim_cap will simply drop this packet, under the
>    assumption that the other side will simply retransmit. Well we do
>    retransmit, and then the packet is just dropped again for the same
>    reason.
> 
> It seems the better way to address this problem is to clear pfmemalloc
> in the TCP transmit path. pfmemalloc strict control really makes sense
> on the receive path. 
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Acked-by: Josef Bacik <jbacik@fb.com>

Applied.