Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264507AbUAFPsv (ORCPT ); Tue, 6 Jan 2004 10:48:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264527AbUAFPsv (ORCPT ); Tue, 6 Jan 2004 10:48:51 -0500 Received: from fw.osdl.org ([65.172.181.6]:41410 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S264507AbUAFPsu (ORCPT ); Tue, 6 Jan 2004 10:48:50 -0500 Date: Tue, 6 Jan 2004 07:48:37 -0800 (PST) From: Linus Torvalds To: Andi Kleen cc: Mika Penttil? , Andi Kleen , David Hinds , linux-kernel@vger.kernel.org Subject: Re: PCI memory allocation bug with CONFIG_HIGHMEM In-Reply-To: <20040106153706.GA63471@colin2.muc.de> Message-ID: References: <1aJdi-7TH-25@gated-at.bofh.it> <20040106040546.GA77287@colin2.muc.de> <20040106081203.GA44540@colin2.muc.de> <3FFA7BB9.1030803@kolumbus.fi> <20040106094442.GB44540@colin2.muc.de> <20040106153706.GA63471@colin2.muc.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1269 Lines: 29 On Tue, 6 Jan 2004, Andi Kleen wrote: > > Anyways, I already implemented reservation for the aperture for the K8 > driver some time ago. And it's in your tree. But it doesn't help for > finding IO holes because there could be other unmarked hardware lurking > there ... Or worse there is just no free space below 4GB. The "unmarked hardware" is why we have PCI quirks. Look at drivers/pci/quirks.c, and notice how many of the quirks are all about quirk_io_region(). Exactly because there isn't any way for the BIOS to tell us about these things on the IO side. (Actually, there is: PnP-BIOS calls are supposed to give us that information. However, not only are the BIOSes buggy and don't give a complete list _anyway_, anybody who uses the PnP-BIOS is much more likely to just get a kernel oops when the BIOS is buggy and assumes that only Windows will call it. So I strongly suggest you not _ever_ use pnp unless you absolutely have to). The same quirks could be done on the MMIO side for northbridges. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/