From b97ea289cf6aff8d4cbcefe2b707bb9b00a73c73 Mon Sep 17 00:00:00 2001 From: Yijing Wang Date: Mon, 16 Mar 2015 11:18:56 +0800 Subject: 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 --- drivers/pci/host/pci-versatile.c | 1 + drivers/pci/probe.c | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') 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); -- cgit v1.2.3