From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [net PATCH] atl1c: Fix misuse of netdev_alloc_skb in refilling
 rx ring
Date: Sun, 28 Jul 2013 16:01:22 -0700
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Cc: Neil Horman <nhorman@tuxdriver.com>,
	David Miller <davem@davemloft.net>,
	luis.henriques@canonical.com, netdev@vger.kernel.org,
	jcliburn@gmail.com, stable@vger.kernel.org
To: Ben Hutchings <bhutchings@solarflare.com>
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On Sun, 2013-07-28 at 21:22 +0100, Ben Hutchings wrote:

> 
> Since we know lengths > 4K work, perhaps it would be worth testing with
> the fragment cache size reduced to 16K?  The driver would never
> previously have used RX buffers crossing 16K boundaries, except if SLOB
> was used (and that's an unlikely combination).

Sure, please note the following maths :

NET_SKB_PAD + 1536 + sizeof(struct skb_shared_info) = 1920

16384/1920 = 8

32768/1920 = 17

I don't think atl1c is used in any critical host (given it doesn't even
provide RX checksums and GRO ...), so I will provide a patch doing mere
page allocations.