From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ben Hutchings <bhutchings@solarflare.com>
Subject: Re: [PATCH 2/4 net-next] tg3: provide frags as skb head
Date: Fri, 27 Apr 2012 17:53:03 +0100
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Cc: David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	Ilpo =?ISO-8859-1?Q?J=E4rvinen?= <ilpo.jarvinen@helsinki.fi>,
	Tom Herbert <therbert@google.com>,
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	Matt Carlson <mcarlson@broadcom.com>,
	Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
	Michael Chan <mchan@broadcom.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, 2012-04-27 at 18:42 +0200, Eric Dumazet wrote:
> On Fri, 2012-04-27 at 17:33 +0100, Ben Hutchings wrote:
> 
> > page_address() may return NULL if CONFIG_HIGHMEM is enabled.  And that's
> > going to be a general problem with this scheme on 32-bit machines.
> 
> kmalloc(2048, GFP_ATOMIC) and alloc_page(GFP_ATOMIC) uses the same pool
> of LOWMEM pages, so there is no difference here. page_address() is
> guaranteed to work.

Oh, of course, GFP_HIGH is not GFP_HIGHMEM...

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.