From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: RE: [PATCH] usb: xhci: Link TRB must not occur with a USB payload
 burst.
Date: Wed, 20 Nov 2013 07:03:47 -0800
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Cc: Alan Stern <stern@rowland.harvard.edu>,
	Sarah Sharp <sarah.a.sharp@linux.intel.com>,
	Ben Hutchings <bhutchings@solarflare.com>,
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To: David Laight <David.Laight@ACULAB.COM>
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On Wed, 2013-11-20 at 09:36 +0000, David Laight wrote:

> Ben said the largest number of fragments from the current network
> stack will be 17, and that none of them will cross 32k boundaries.
> So the network stack won't send down long SG lists.

Please note that skb->head itself _might_ cross a 32K or 64K boundary :

skb->head is kmalloc() provided, and SLUB can be tweaked
(slub_max_order) to use very high order pages.