From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kenji Kaneshige Subject: [PATCH 2/8] PCI/ACPI: fix wrong assumption in acpi_find_root_bridge_handle Date: Wed, 28 Jan 2009 20:50:29 +0900 Message-ID: <49804685.5030404@jp.fujitsu.com> 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> <498045D1.60005@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <498045D1.60005@jp.fujitsu.com> Sender: linux-pci-owner@vger.kernel.org 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 List-Id: linux-acpi@vger.kernel.org Current acpi_find_root_bridge_handle() has a assumption that pci_bus->self is NULL on the root pci bus. But it might not be true on some platforms. Because of this wrong assumption, current acpi_find_root_bridge_handle() might cause endless loop. We must check pci_bus->parent instead. Signed-off-by: Kenji Kaneshige --- include/linux/pci-acpi.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) Index: linux-2.6.29-rc2/include/linux/pci-acpi.h =================================================================== --- linux-2.6.29-rc2.orig/include/linux/pci-acpi.h +++ linux-2.6.29-rc2/include/linux/pci-acpi.h @@ -53,12 +53,12 @@ extern acpi_status pci_osc_control_set(a int pci_acpi_osc_support(acpi_handle handle, u32 flags); static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev) { - /* Find root host bridge */ - while (pdev->bus->self) - pdev = pdev->bus->self; - - return acpi_get_pci_rootbridge_handle(pci_domain_nr(pdev->bus), - pdev->bus->number); + struct pci_bus *pbus = pdev->bus; + /* Find a PCI root bus */ + while (pbus->parent) + pbus = pbus->parent; + return acpi_get_pci_rootbridge_handle(pci_domain_nr(pbus), + pbus->number); } static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)