From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] skb: Propagate pfmemalloc on skb from head page only
Date: Thu, 14 Mar 2013 15:34:09 +0100
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Cc: David Miller <davem@davemloft.net>, Mel Gorman <mgorman@suse.de>,
	Linux Netdev List <netdev@vger.kernel.org>,
	stable@kernel.org, Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
To: Pavel Emelyanov <xemul@parallels.com>
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On Thu, 2013-03-14 at 18:23 +0400, Pavel Emelyanov wrote:

> Presumably you're right, but I don't understand how :( In order to trigger
> this, we should have a huge page, that gets linked to an skb _before_ it
> enters the TCP receive path. How can this happen when doing sendmsg/recvmsg?

Not only huge pages.

network now uses order-3 pages in both transmit and receive paths.