Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750923AbWIADU7 (ORCPT ); Thu, 31 Aug 2006 23:20:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750927AbWIADU7 (ORCPT ); Thu, 31 Aug 2006 23:20:59 -0400 Received: from smtp.cce.hp.com ([161.114.21.23]:15786 "EHLO ccerelrim02.cce.hp.com") by vger.kernel.org with ESMTP id S1750914AbWIADU5 (ORCPT ); Thu, 31 Aug 2006 23:20:57 -0400 Message-ID: <49303.24.9.204.52.1157080555.squirrel@mail.cce.hp.com> In-Reply-To: <1157073592.5649.29.camel@keithlap> References: <200608310248.29861.len.brown@intel.com> <1157042913.7859.31.camel@keithlap> <200608311707.00817.bjorn.helgaas@hp.com> <1157073592.5649.29.camel@keithlap> Date: Thu, 31 Aug 2006 21:15:55 -0600 (MDT) Subject: Re: one more ACPI Error (utglobal-0125): Unknown exception code: 0xFFFFFFEA [Re: 2.6.18-rc4-mm3] From: "Bjorn Helgaas" To: kmannth@us.ibm.com Cc: "Bjorn Helgaas" , "Len Brown" , "Moore, Robert" , "Li, Shaohua" , "Mattia Dongili" , "Andrew Morton" , "lkml" , "linux acpi" , "KAMEZAWA Hiroyuki" User-Agent: SquirrelMail/1.4.8 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Priority: 3 (Normal) Importance: Normal X-PMX-Version: 5.1.2.240295, Antispam-Engine: 2.3.0.1, Antispam-Data: 2006.8.31.195942 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2119 Lines: 47 > On Thu, 2006-08-31 at 17:06 -0600, Bjorn Helgaas wrote: >> Problem 1: acpi_reserve_io_ranges() needs to return an acpi_status >> like AE_OK or AE_CTRL_TERMINATE, not a -EINVAL. > > Sure great sounds. I understand AE_OK is a 0 return so I can change it > to AE_CTRL_TERMINATE. I don't want acpi_reserve_io_ranges to return a > happy state when if finds a resource type is doesn't know. Except that when the motherboard driver claims a device, it really should claim all the resources used by the device. It currently only claims I/O port resources, but I think it should also claim MMIO resources. Otherwise, the system resource accounting is screwed up, and resources consumed by the motherboard device could be mistakenly allocated to another device. > Kame (who helped me greatly in tracking down the source my troubles) > thinks that the root cause is that the device (my memory_device) has > both a _HID and _CID. The driver for _HID is different for _CID and the > driver for _CID is found before _HID and I pass the wrong device up the > chain. Ok, this is starting to make sense. It sounds like your memory device has _HID of PNP0C80 and _CID of PNP0C01 (or PNP0C02). The current ACPI driver binding algorithm in acpi_bus_find_driver() looks at each driver, checking whether it can match either the _HID or the _CID of a device. Since we try the motherboard driver first, it matches the memory device _CID. I couldn't find a specific reference in the spec, but this seems intuitively sub-optimal. It seems like it'd be better to look first for a driver that can claim the _HID (which is more specific), and only fall back to checking the _CIDs if no _HID-specific driver is found. This looks fairly easy to do in ACPI. Not so easy in PNPACPI, since I don't think PNP has the concept of _HID vs _CID. Maybe Len will chime in with an opinion. Bjorn - 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/