From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC] skb truesize last offenders
Date: Fri, 23 Mar 2012 11:55:19 -0700
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	 <20120323.143826.1042705555491529895.davem@davemloft.net>
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Cc: netdev@vger.kernel.org, wey-yi.w.guy@intel.com,
	Neal Cardwell <ncardwell@google.com>
To: David Miller <davem@davemloft.net>
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On Fri, 2012-03-23 at 14:38 -0400, David Miller wrote:
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Fri, 23 Mar 2012 05:51:52 -0700
> 
> > iwlwifi and some other users of skb_add_rx_frag() lie about skb
> > truesize, because of API being lazy.
> > 
> > iwlwifi can use order-0 or order-1 pages and skb truesize is wrong.
> > network sbs can use uncharged kernel memory and eventually crash machine
> > in OOM.
> > 
> > I plan : 
> > 
> > 1) adding a @truesize parameter to skb_add_rx_frag() in a neutral patch
> > 
> > 2) fix drivers that dont charge the real size of fragment
> > 
> > 3) niu could then use skb_add_rx_frag() instead of custom code.
> 
> No objections from me.  But we really have to fix that
> tcp_grow_window() issue, it's quite urgent if you ask me.

Sure, I can work on this issue with Neal asap, we do have some ideas on
this subject.