From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 2/4 net-next] tg3: provide frags as skb head Date: Fri, 27 Apr 2012 12:38:36 -0400 (EDT) Message-ID: <20120427.123836.690112554674540119.davem@davemloft.net> References: <1335522889.2775.231.camel@edumazet-glaptop> <1335544386.2618.50.camel@bwh-desktop.uk.solarflarecom.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: eric.dumazet@gmail.com, netdev@vger.kernel.org, ilpo.jarvinen@helsinki.fi, therbert@google.com, ncardwell@google.com, mcarlson@broadcom.com, jeffrey.t.kirsher@intel.com, mchan@broadcom.com, herbert@gondor.hengli.com.au, maze@google.com To: bhutchings@solarflare.com Return-path: Received: from shards.monkeyblade.net ([198.137.202.13]:43561 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760438Ab2D0Qi5 (ORCPT ); Fri, 27 Apr 2012 12:38:57 -0400 In-Reply-To: <1335544386.2618.50.camel@bwh-desktop.uk.solarflarecom.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Ben Hutchings Date: Fri, 27 Apr 2012 17:33:06 +0100 > 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. It can only be NULL for highmem pages, which he is not going to get from the kind of page allocation calls he is using.