From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760203AbYCCVlz (ORCPT ); Mon, 3 Mar 2008 16:41:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755681AbYCCVlo (ORCPT ); Mon, 3 Mar 2008 16:41:44 -0500 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:56649 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754296AbYCCVln (ORCPT ); Mon, 3 Mar 2008 16:41:43 -0500 Date: Mon, 3 Mar 2008 21:29:55 +0000 From: Alan Cox To: benh@kernel.crashing.org Cc: Jesse Barnes , linux-pci@atrey.karlin.mff.cuni.cz, Linux Kernel list , Matthew Wilcox Subject: Re: Weirdness in pci_read_bases() Message-ID: <20080303212955.1c0f29c7@core> In-Reply-To: <1204576954.21545.10.camel@pasglop> References: <1204252667.15052.402.camel@pasglop> <200803031112.27658.jbarnes@virtuousgeek.org> <1204576954.21545.10.camel@pasglop> X-Mailer: Claws Mail 3.2.0 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > The main question regarding 0 in a BAR is do we know of devices that > consider it as "disabled" and don't operate/decode 0 ? (That would be > gross and out of spec but who knows...) In the PC world it never gets tested so it might be wise to be cautious. > But that can be solved, using something akin to IORESOURCE_UNSET, like > we do on powerpc, generalizing it, and having an x86-specific quirk set > it on anything that comes up with resource->start == 0. And add pci_resource_unassigned() to wrap it nicely. That would definitely be a good thing as we have confusion right now and it has turned up in the real world. Alan