From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [E1000-devel] [next:akpm 16/587]
 drivers/net/ethernet/intel/igb/igb_main.c:6231:2: error: call to
 '__compiletime_assert_6235' declared with attribute error: BUILD_BUG_ON
 failed: SKB_WITH_OVERHEAD(IGB_RX_BUFSZ) < (NET_SKB_PAD + NET_IP_ALIGN +
 IGB_TS_HDR_LEN + ETH...
Date: Wed, 20 Feb 2013 11:22:36 -0800
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Cc: "Allan, Bruce W" <bruce.w.allan@intel.com>,
	"e1000-devel@lists.sourceforge.net"
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	Daniel Santos <daniel.santos@pobox.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	"Wu, Fengguang" <fengguang.wu@intel.com>
To: Alexander Duyck <alexander.h.duyck@intel.com>
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On Wed, 2013-02-20 at 10:16 -0800, Alexander Duyck wrote:

> 
> The problem is the 256 byte alignment for L1_CACHE_BYTES is increasing
> the size of the data and shared info significantly pushing us past the
> 2K limit.
> 
> I'll look into this since it likely affects ixgbe as well.

Thats what I said.

Using 256 bytes of headroom is silly.

We should limit NET_SKB_PAD to the 32-64 range