From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] net: Use NLMSG_DEFAULT_SIZE in combination with
 nlmsg_new()
Date: Thu, 28 Jun 2012 16:55:49 +0200
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References: <caecbaa2f181c17908fbd61264e1acb9c5cb1fe1.1340891841.git.tgraf@suug.ch>
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Cc: davem@davemloft.net, netdev@vger.kernel.org,
	Jiri Pirko <jpirko@redhat.com>,
	Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>,
	Sergey Lapin <slapin@ossfans.org>,
	Johannes Berg <johannes@sipsolutions.net>,
	Lauro Ramos Venancio <lauro.venancio@openbossa.org>,
	Aloisio Almeida Jr <aloisio.almeida@openbossa.org>,
	Samuel Ortiz <sameo@linux.intel.com>
To: Thomas Graf <tgraf@suug.ch>
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On Thu, 2012-06-28 at 15:57 +0200, Thomas Graf wrote:
> Using NLMSG_GOODSIZE results in multiple pages being used as
> nlmsg_new() will automatically add the size of the netlink
> header to the payload thus exceeding the page limit.

On the other hand, this limits to 3776 bytes for each recvmsg() call.

Maybe this can add a regression if one of the file needed to store more
than 3776 bytes in the answer ?

For GFP_KERNEL allocations, I am not sure we really need to limit to
order-0 pages...

Unless you can point a real bug, this patch is not for net tree, but
net-next.