Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754575AbZA1Lr6 (ORCPT ); Wed, 28 Jan 2009 06:47:58 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751334AbZA1Lrs (ORCPT ); Wed, 28 Jan 2009 06:47:48 -0500 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:60244 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751241AbZA1Lrr (ORCPT ); Wed, 28 Jan 2009 06:47:47 -0500 Message-ID: <498045D1.60005@jp.fujitsu.com> Date: Wed, 28 Jan 2009 20:47:29 +0900 From: Kenji Kaneshige User-Agent: Thunderbird 2.0.0.19 (Windows/20081209) MIME-Version: 1.0 To: linux-pci@vger.kernel.org, "Barnes, Jesse" CC: James Bottomley , Len Brown , linux-acpi@vger.kernel.org, linux-kernel , shaohua.li@intel.com, Grant Grundler Subject: Re: ACPI hotplug panic with current git head References: <1231604250.3642.33.camel@localhost.localdomain> <1231807693.27151.21.camel@localhost.localdomain> <1232046108.5966.57.camel@localhost.localdomain> <1232049269.5966.64.camel@localhost.localdomain> <1232050347.5966.66.camel@localhost.localdomain> <4970242C.4010404@jp.fujitsu.com> <1232115546.3224.5.camel@localhost.localdomain> <4973D2EE.3060203@jp.fujitsu.com> <1232328216.3247.68.camel@localhost.localdomain> <4973EF64.2050404@jp.fujitsu.com> <1232558780.736.24.camel@localhost.localdomain> <497D1BD7.9000609@jp.fujitsu.com> In-Reply-To: <497D1BD7.9000609@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2865 Lines: 73 Kenji Kaneshige wrote: > James Bottomley wrote: >> On Mon, 2009-01-19 at 12:11 +0900, Kenji Kaneshige wrote: >>> I'm sending the debug patch against 2.6.29-rc1 below. I'm also >>> sending it as an attachment. It also contains the code to prevent >>> the kernel panic from you. Please note that you will see two >>> WARN_ON(1) messages with the patch. Those are shown by my debug >>> patch. >>> >>> Could you try it and send me the whole dmsg output? >> Actually, the machine is now running -rc2, so the patch doesn't quite >> apply: >> >> jejb@sparkweed> patch -p1 < ~/tmp.diff >> patching file include/linux/pci-acpi.h >> patching file drivers/pci/hotplug/acpiphp_glue.c >> Hunk #1 FAILED at 266. >> Hunk #2 succeeded at 467 (offset 2 lines). >> Hunk #3 succeeded at 489 (offset 2 lines). >> Hunk #4 succeeded at 518 (offset 2 lines). >> Hunk #5 succeeded at 556 (offset 2 lines). >> >> Looks like the rejection is in the NULL check piece, so I've already >> actually sent you the information it would produce. >> >> The dmesg output is pretty big, below. >> > > Thank you very much, James. > > Thanks to you, I found the root cause of the > problem. The acpi_pci_get_bridge_handle() function assumes > pci_bus->self is NULL on the root bus. But it is not true > and pci_bus->self can have a non-NULL value on some > platfroms (like yours). So it must check pci_bus->parent > instead. > > I found some other code that has the same wrong assumption. > I'll make a fix for them and send it soon. > I made several patches to fix the wrong assumption described above. It is very difficult for me to check all the code that refers pci_bus->self. So I checked include/linux/pci-acpi.h and the code under drivers/pci/ only. And I made patches for the code like below: - The code that clearly chooses host bridge operation or PCI-to-PCI bridge operation based on pci_bus->self. - The code that might cause endless loop if pci_bus->self is not NULL on the PCI root bus. The patches are - [PATCH 1/8] PCI/ACPI: fix wrong assumption in acpi_pci_get_bridge_handle - [PATCH 2/8] PCI/ACPI: fix wrong assumption in acpi_find_root_bridge_handle - [PATCH 3/8] PCI hotplug: fix wrong assumption in acpi_get_hp_params_from_firmware - [PATCH 4/8] PCI hotplug: fix wrong assumption in acpi_get_hp_hw_control_from_firmware - [PATCH 5/8] PCI: fix wrong assumption in pci_find_upstream_pcie_bridge - [PATCH 6/8] PCI: fix wrong assumption in pci_read_bridge_bases - [PATCH 7/8] PCI: fix wrong assumption in pci_get_interrupt_pin - [PATCH 8/8] PCI: fix wrong assumption in pci_common_swizzle Thanks, Kenji Kaneshige -- 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/