From b97ea289cf6aff8d4cbcefe2b707bb9b00a73c73 Mon Sep 17 00:00:00 2001 From: Yijing Wang Date: Mon, 16 Mar 2015 11:18:56 +0800 Subject: [PATCH] PCI: Assign resources before drivers claim devices (pci_scan_root_bus()) Previously, pci_scan_root_bus() created a root PCI bus, enumerated the devices on it, and called pci_bus_add_devices(), which made the devices available for drivers to claim them. Most callers assigned resources to devices after pci_scan_root_bus() returns, which may be after drivers have claimed the devices. This is incorrect; the PCI core should not change device resources while a driver is managing the device. Remove pci_bus_add_devices() from pci_scan_root_bus() and do it after any resource assignment in the callers. Note that ARM's pci_common_init_dev() already called pci_bus_add_devices() after pci_scan_root_bus(), so we only need to remove the first call: pci_common_init_dev pcibios_init_hw pci_scan_root_bus pci_bus_add_devices # first call pci_bus_assign_resources pci_bus_add_devices # second call [bhelgaas: changelog, drop "root_bus" var in alpha common_init_pci(), return failure earlier in mn10300, add "return" in x86 pcibios_scan_root(), return early if xtensa platform_pcibios_fixup() fails] Signed-off-by: Yijing Wang Signed-off-by: Bjorn Helgaas CC: Richard Henderson CC: Ivan Kokshaysky CC: Matt Turner CC: David Howells CC: Tony Luck CC: Michal Simek CC: Ralf Baechle CC: Koichi Yasutake CC: Sebastian Ott CC: "David S. Miller" CC: Chris Metcalf CC: Chris Zankel CC: Max Filippov CC: Thomas Gleixner --- arch/alpha/kernel/pci.c | 7 +++++++ arch/frv/mb93090-mb00/pci-vdk.c | 6 +++++- arch/ia64/sn/kernel/io_init.c | 2 ++ arch/microblaze/pci/pci-common.c | 4 ++++ arch/mips/pci/pci.c | 1 + arch/mn10300/unit-asb2305/pci.c | 6 +++++- arch/s390/pci/pci.c | 2 +- arch/sh/drivers/pci/pci.c | 1 + arch/sparc/kernel/leon_pci.c | 1 + arch/tile/kernel/pci.c | 2 ++ arch/tile/kernel/pci_gx.c | 2 ++ arch/x86/pci/common.c | 2 ++ arch/xtensa/kernel/pci.c | 15 +++++++++++++-- drivers/pci/host/pci-versatile.c | 1 + drivers/pci/probe.c | 1 - 15 files changed, 47 insertions(+), 6 deletions(-) diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c index 98a1525fa164..82f738e5d54c 100644 --- a/arch/alpha/kernel/pci.c +++ b/arch/alpha/kernel/pci.c @@ -338,6 +338,8 @@ common_init_pci(void) bus = pci_scan_root_bus(NULL, next_busno, alpha_mv.pci_ops, hose, &resources); + if (!bus) + continue; hose->bus = bus; hose->need_domain_info = need_domain_info; next_busno = bus->busn_res.end + 1; @@ -353,6 +355,11 @@ common_init_pci(void) pci_assign_unassigned_resources(); pci_fixup_irqs(alpha_mv.pci_swizzle, alpha_mv.pci_map_irq); + for (hose = hose_head; hose; hose = hose->next) { + bus = hose->bus; + if (bus) + pci_bus_add_devices(bus); + } } diff --git a/arch/frv/mb93090-mb00/pci-vdk.c b/arch/frv/mb93090-mb00/pci-vdk.c index b073f4d771a5..f211839e2cae 100644 --- a/arch/frv/mb93090-mb00/pci-vdk.c +++ b/arch/frv/mb93090-mb00/pci-vdk.c @@ -316,6 +316,7 @@ void pcibios_fixup_bus(struct pci_bus *bus) int __init pcibios_init(void) { + struct pci_bus *bus; struct pci_ops *dir = NULL; LIST_HEAD(resources); @@ -383,12 +384,15 @@ int __init pcibios_init(void) printk("PCI: Probing PCI hardware\n"); pci_add_resource(&resources, &pci_ioport_resource); pci_add_resource(&resources, &pci_iomem_resource); - pci_scan_root_bus(NULL, 0, pci_root_ops, NULL, &resources); + bus = pci_scan_root_bus(NULL, 0, pci_root_ops, NULL, &resources); pcibios_irq_init(); pcibios_fixup_irqs(); pcibios_resource_survey(); + if (!bus) + return 0; + pci_bus_add_devices(bus); return 0; } diff --git a/arch/ia64/sn/kernel/io_init.c b/arch/ia64/sn/kernel/io_init.c index 0b5ce82d203d..1be65eb074ec 100644 --- a/arch/ia64/sn/kernel/io_init.c +++ b/arch/ia64/sn/kernel/io_init.c @@ -271,7 +271,9 @@ sn_pci_controller_fixup(int segment, int busnum, struct pci_bus *bus) if (bus == NULL) { kfree(res); kfree(controller); + return; } + pci_bus_add_devices(bus); } /* diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c index 48528fb81eff..ae838ed5fcf2 100644 --- a/arch/microblaze/pci/pci-common.c +++ b/arch/microblaze/pci/pci-common.c @@ -1382,6 +1382,10 @@ static int __init pcibios_init(void) /* Call common code to handle resource allocation */ pcibios_resource_survey(); + list_for_each_entry_safe(hose, tmp, &hose_list, list_node) { + if (hose->bus) + pci_bus_add_devices(hose->bus); + } return 0; } diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c index 1bf60b127377..9eb54b557c9f 100644 --- a/arch/mips/pci/pci.c +++ b/arch/mips/pci/pci.c @@ -114,6 +114,7 @@ static void pcibios_scanbus(struct pci_controller *hose) pci_bus_size_bridges(bus); pci_bus_assign_resources(bus); } + pci_bus_add_devices(bus); } } diff --git a/arch/mn10300/unit-asb2305/pci.c b/arch/mn10300/unit-asb2305/pci.c index 613ca1e55b4b..3dfe2d31c67b 100644 --- a/arch/mn10300/unit-asb2305/pci.c +++ b/arch/mn10300/unit-asb2305/pci.c @@ -342,6 +342,7 @@ static int __init pcibios_init(void) { resource_size_t io_offset, mem_offset; LIST_HEAD(resources); + struct pci_bus *bus; ioport_resource.start = 0xA0000000; ioport_resource.end = 0xDFFFFFFF; @@ -371,11 +372,14 @@ static int __init pcibios_init(void) pci_add_resource_offset(&resources, &pci_ioport_resource, io_offset); pci_add_resource_offset(&resources, &pci_iomem_resource, mem_offset); - pci_scan_root_bus(NULL, 0, &pci_direct_ampci, NULL, &resources); + bus = pci_scan_root_bus(NULL, 0, &pci_direct_ampci, NULL, &resources); + if (!bus) + return 0; pcibios_irq_init(); pcibios_fixup_irqs(); pcibios_resource_survey(); + pci_bus_add_devices(bus); return 0; } diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c index 753a56731951..a2a7391c0b9a 100644 --- a/arch/s390/pci/pci.c +++ b/arch/s390/pci/pci.c @@ -776,8 +776,8 @@ static int zpci_scan_bus(struct zpci_dev *zdev) zpci_cleanup_bus_resources(zdev); return -EIO; } - zdev->bus->max_bus_speed = zdev->max_bus_speed; + pci_bus_add_devices(zdev->bus); return 0; } diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c index 1bc09ee7948f..efc10519916a 100644 --- a/arch/sh/drivers/pci/pci.c +++ b/arch/sh/drivers/pci/pci.c @@ -69,6 +69,7 @@ static void pcibios_scanbus(struct pci_channel *hose) pci_bus_size_bridges(bus); pci_bus_assign_resources(bus); + pci_bus_add_devices(bus); } else { pci_free_resource_list(&resources); } diff --git a/arch/sparc/kernel/leon_pci.c b/arch/sparc/kernel/leon_pci.c index 899b7203a4e4..297107679fdf 100644 --- a/arch/sparc/kernel/leon_pci.c +++ b/arch/sparc/kernel/leon_pci.c @@ -40,6 +40,7 @@ void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info) /* Assign devices with resources */ pci_assign_unassigned_resources(); + pci_bus_add_devices(root_bus); } else { pci_free_resource_list(&resources); } diff --git a/arch/tile/kernel/pci.c b/arch/tile/kernel/pci.c index 325df47f114d..9475a74cd53a 100644 --- a/arch/tile/kernel/pci.c +++ b/arch/tile/kernel/pci.c @@ -339,6 +339,8 @@ int __init pcibios_init(void) struct pci_bus *next_bus; struct pci_dev *dev; + pci_bus_add_devices(root_bus); + list_for_each_entry(dev, &root_bus->devices, bus_list) { /* * Find the PCI host controller, ie. the 1st diff --git a/arch/tile/kernel/pci_gx.c b/arch/tile/kernel/pci_gx.c index 2c95f37ebbed..b1df847d0686 100644 --- a/arch/tile/kernel/pci_gx.c +++ b/arch/tile/kernel/pci_gx.c @@ -1030,6 +1030,8 @@ int __init pcibios_init(void) alloc_mem_map_failed: break; } + + pci_bus_add_devices(root_bus); } return 0; diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c index 3d2612b68694..95a0ba70376b 100644 --- a/arch/x86/pci/common.c +++ b/arch/x86/pci/common.c @@ -490,7 +490,9 @@ void pcibios_scan_root(int busnum) if (!bus) { pci_free_resource_list(&resources); kfree(sd); + return; } + pci_bus_add_devices(bus); } void __init pcibios_set_cache_line_size(void) diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c index 5b3403388d7f..b848cc3dc913 100644 --- a/arch/xtensa/kernel/pci.c +++ b/arch/xtensa/kernel/pci.c @@ -174,7 +174,7 @@ static int __init pcibios_init(void) struct pci_controller *pci_ctrl; struct list_head resources; struct pci_bus *bus; - int next_busno = 0; + int next_busno = 0, ret; printk("PCI: Probing PCI hardware\n"); @@ -185,14 +185,25 @@ static int __init pcibios_init(void) pci_controller_apertures(pci_ctrl, &resources); bus = pci_scan_root_bus(NULL, pci_ctrl->first_busno, pci_ctrl->ops, pci_ctrl, &resources); + if (!bus) + continue; + pci_ctrl->bus = bus; pci_ctrl->last_busno = bus->busn_res.end; if (next_busno <= pci_ctrl->last_busno) next_busno = pci_ctrl->last_busno+1; } pci_bus_count = next_busno; + ret = platform_pcibios_fixup(); + if (ret) + return ret; - return platform_pcibios_fixup(); + for (pci_ctrl = pci_ctrl_head; pci_ctrl; pci_ctrl = pci_ctrl->next) { + if (pci_ctrl->bus) + pci_bus_add_devices(pci_ctrl->bus); + } + + return 0; } subsys_initcall(pcibios_init); diff --git a/drivers/pci/host/pci-versatile.c b/drivers/pci/host/pci-versatile.c index 1ec694a52379..e3a2450db2b8 100644 --- a/drivers/pci/host/pci-versatile.c +++ b/drivers/pci/host/pci-versatile.c @@ -214,6 +214,7 @@ static int versatile_pci_probe(struct platform_device *pdev) pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); pci_assign_unassigned_bus_resources(bus); + pci_bus_add_devices(bus); return 0; } diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 88604f29d140..8ef0375ea314 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2087,7 +2087,6 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus, if (!found) pci_bus_update_busn_res_end(b, max); - pci_bus_add_devices(b); return b; } EXPORT_SYMBOL(pci_scan_root_bus); -- 2.20.1