This is a note to let you know that I've just added the patch titled powerpc/eeh: Fix crash when adding a device in a slot with DDW to the 3.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-eeh-fix-crash-when-adding-a-device-in-a-slot-with-ddw.patch and it can be found in the queue-3.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 6a040ce72598159a74969a2d01ab0ba5ee6536b3 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxxxxxxx> Date: Fri, 28 Dec 2012 09:13:19 +0000 Subject: powerpc/eeh: Fix crash when adding a device in a slot with DDW From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxxxxxxx> commit 6a040ce72598159a74969a2d01ab0ba5ee6536b3 upstream. 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. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxxxxxxx> Acked-by: Gavin Shan <shangw@xxxxxxxxxxxxxxxxxx> Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/eeh.h | 3 +++ arch/powerpc/kernel/of_platform.c | 3 +++ arch/powerpc/kernel/pci-common.c | 7 +++++-- arch/powerpc/platforms/pseries/eeh.c | 24 +++++++++++++++++++++++- 4 files changed, 34 insertions(+), 3 deletions(-) --- 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 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_sysfs_files(struct pci_bus *); void eeh_remove_bus_device(struct pci_dev *, int); /** @@ -240,6 +241,8 @@ static inline void eeh_add_device_tree_e static inline void eeh_add_device_tree_late(struct pci_bus *bus) { } +static inline void eeh_add_sysfs_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) { } --- a/arch/powerpc/kernel/of_platform.c +++ b/arch/powerpc/kernel/of_platform.c @@ -95,6 +95,9 @@ static int of_pci_phb_probe(struct platf /* Add probed PCI devices to the device model */ pci_bus_add_devices(phb->bus); + /* sysfs files should only be added after devices are added */ + eeh_add_sysfs_files(phb->bus); + return 0; } --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -1477,11 +1477,14 @@ void pcibios_finish_adding_to_bus(struct 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); + /* sysfs files should only be added after devices are added */ + eeh_add_sysfs_files(bus); } EXPORT_SYMBOL_GPL(pcibios_finish_adding_to_bus); --- 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 p 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 EXPORT_SYMBOL_GPL(eeh_add_device_tree_late); /** + * eeh_add_sysfs_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_sysfs_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_sysfs_files(subbus); + } + } +} +EXPORT_SYMBOL_GPL(eeh_add_sysfs_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 Patches currently in stable-queue which might be from cascardo@xxxxxxxxxxxxxxxxxx are queue-3.8/powerpc-eeh-fix-crash-when-adding-a-device-in-a-slot-with-ddw.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html