From patchwork Thu Dec 27 16:34:00 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thadeu Lima de Souza Cascardo X-Patchwork-Id: 208342 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id A80292C0080 for ; Fri, 28 Dec 2012 03:36:15 +1100 (EST) Received: from e24smtp04.br.ibm.com (e24smtp04.br.ibm.com [32.104.18.25]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e24smtp04.br.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 3AB5D2C00D2 for ; Fri, 28 Dec 2012 03:34:52 +1100 (EST) Received: from /spool/local by e24smtp04.br.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Thu, 27 Dec 2012 14:34:46 -0200 Received: from d24relay02.br.ibm.com (d24relay02.br.ibm.com [9.13.184.26]) by d24dlp02.br.ibm.com (Postfix) with ESMTP id 105EC1DC0050 for ; Thu, 27 Dec 2012 11:34:46 -0500 (EST) Received: from d24av01.br.ibm.com (d24av01.br.ibm.com [9.8.31.91]) by d24relay02.br.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id qBRGYNoI33816770 for ; Thu, 27 Dec 2012 14:34:23 -0200 Received: from d24av01.br.ibm.com (loopback [127.0.0.1]) by d24av01.br.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id qBRGYjkP016737 for ; Thu, 27 Dec 2012 14:34:45 -0200 Received: from oc0268524204.ibm.com (susilva.br.ibm.com [9.18.196.231] (may be forged)) by d24av01.br.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id qBRGYiDX016731; Thu, 27 Dec 2012 14:34:45 -0200 From: Thadeu Lima de Souza Cascardo To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH] ppc/EEH: fix crash when adding a device in a slot with DDW Date: Thu, 27 Dec 2012 14:34:00 -0200 Message-Id: <1356626040-9384-1-git-send-email-cascardo@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.1 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12122716-8936-0000-0000-000008E9B9C0 Cc: shangw@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org, paulus@samba.org, Thadeu Lima de Souza Cascardo , bhelgaas@google.com X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" The DDW code uses a eeh_dev struct from the pci_dev. However, this is not set until eeh_add_device_late is called. Since pci_bus_add_devices is called before eeh_add_device_late, the PCI devices are added to the bus, making drivers' probe hooks to be called. These will call set_dma_mask, which will call the DDW code, which will require the eeh_dev struct from pci_dev. This would result in a crash, due to a NULL dereference. Calling eeh_add_device_late after pci_bus_add_devices would make the system BUG, because device files shouldn't be added to devices there were not added to the system. So, a new function is needed to add such files only after pci_bus_add_devices have been called. Cc: stable@vger.kernel.org Signed-off-by: Thadeu Lima de Souza Cascardo --- arch/powerpc/include/asm/eeh.h | 3 +++ arch/powerpc/kernel/pci-common.c | 7 +++++-- arch/powerpc/platforms/pseries/eeh.c | 24 +++++++++++++++++++++++- 3 files changed, 31 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index b0ef738..71aac19 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -201,6 +201,7 @@ int eeh_dev_check_failure(struct eeh_dev *edev); void __init eeh_addr_cache_build(void); void eeh_add_device_tree_early(struct device_node *); void eeh_add_device_tree_late(struct pci_bus *); +void eeh_add_device_tree_files(struct pci_bus *); void eeh_remove_bus_device(struct pci_dev *, int); /** @@ -240,6 +241,8 @@ static inline void eeh_add_device_tree_early(struct device_node *dn) { } static inline void eeh_add_device_tree_late(struct pci_bus *bus) { } +static inline void eeh_add_device_tree_files(struct pci_bus *bus) { } + static inline void eeh_remove_bus_device(struct pci_dev *dev, int purge_pe) { } static inline void eeh_lock(void) { } diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 7f94f76..7b1f14c 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -1480,11 +1480,14 @@ void pcibios_finish_adding_to_bus(struct pci_bus *bus) pcibios_allocate_bus_resources(bus); pcibios_claim_one_bus(bus); + /* Fixup EEH */ + eeh_add_device_tree_late(bus); + /* Add new devices to global lists. Register in proc, sysfs. */ pci_bus_add_devices(bus); - /* Fixup EEH */ - eeh_add_device_tree_late(bus); + /* Add EEH sysfs files */ + eeh_add_device_tree_files(bus); } EXPORT_SYMBOL_GPL(pcibios_finish_adding_to_bus); diff --git a/arch/powerpc/platforms/pseries/eeh.c b/arch/powerpc/platforms/pseries/eeh.c index 9a04322..a667a34 100644 --- a/arch/powerpc/platforms/pseries/eeh.c +++ b/arch/powerpc/platforms/pseries/eeh.c @@ -788,7 +788,6 @@ static void eeh_add_device_late(struct pci_dev *dev) dev->dev.archdata.edev = edev; eeh_addr_cache_insert_dev(dev); - eeh_sysfs_add_device(dev); } /** @@ -815,6 +814,29 @@ void eeh_add_device_tree_late(struct pci_bus *bus) EXPORT_SYMBOL_GPL(eeh_add_device_tree_late); /** + * eeh_add_device_tree_files - Add EEH sysfs files for the indicated PCI bus + * @bus: PCI bus + * + * This routine must be used to add EEH sysfs files for PCI + * devices which are attached to the indicated PCI bus. The PCI bus + * is added after system boot through hotplug or dlpar. + */ +void eeh_add_device_tree_files(struct pci_bus *bus) +{ + struct pci_dev *dev; + + list_for_each_entry(dev, &bus->devices, bus_list) { + eeh_sysfs_add_device(dev); + if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { + struct pci_bus *subbus = dev->subordinate; + if (subbus) + eeh_add_device_tree_files(subbus); + } + } +} +EXPORT_SYMBOL_GPL(eeh_add_device_tree_files); + +/** * eeh_remove_device - Undo EEH setup for the indicated pci device * @dev: pci device to be removed * @purge_pe: remove the PE or not