From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753995AbZBQV0J (ORCPT ); Tue, 17 Feb 2009 16:26:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751252AbZBQVZx (ORCPT ); Tue, 17 Feb 2009 16:25:53 -0500 Received: from mga06.intel.com ([134.134.136.21]:22154 "EHLO orsmga101.jf.intel.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751118AbZBQVZx (ORCPT ); Tue, 17 Feb 2009 16:25:53 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.38,225,1233561600"; d="scan'208";a="387573825" Message-ID: <499B2B5F.2070407@linux.intel.com> Date: Tue, 17 Feb 2009 13:25:51 -0800 From: "H. Peter Anvin" Organization: Intel Open Source Technology Center User-Agent: Thunderbird 2.0.0.19 (X11/20090105) MIME-Version: 1.0 To: James Bottomley CC: hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org Subject: Re: [tip:x86/headers] x86: truncate ISA addresses to unsigned int References: <1234905865.23466.11.camel@localhost.localdomain> In-Reply-To: <1234905865.23466.11.camel@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org James Bottomley wrote: >> +static inline unsigned int isa_virt_to_bus(volatile void *address) > > The rest looks fine, but why is the address volatile? The macro below > never actually dereferences it. > Because a volatile is permitted. virt_to_phys() takes a volatile pointer for that reason. -hpa