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 <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
CC: Matt Turner <mattst88@gmail.com>
CC: David Howells <dhowells@redhat.com>
CC: Tony Luck <tony.luck@intel.com>
CC: Michal Simek <monstr@monstr.eu>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: Chris Metcalf <cmetcalf@ezchip.com>
CC: Chris Zankel <chris@zankel.net>
CC: Max Filippov <jcmvbkbc@gmail.com>
CC: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c
index 98a1525..82f738e 100644
--- a/arch/alpha/kernel/pci.c
+++ b/arch/alpha/kernel/pci.c
@@ -338,6 +338,8 @@
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 @@
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 b073f4d..f211839 100644
--- a/arch/frv/mb93090-mb00/pci-vdk.c
+++ b/arch/frv/mb93090-mb00/pci-vdk.c
@@ -316,6 +316,7 @@
int __init pcibios_init(void)
{
+ struct pci_bus *bus;
struct pci_ops *dir = NULL;
LIST_HEAD(resources);
@@ -383,12 +384,15 @@
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 0b5ce82..1be65eb 100644
--- a/arch/ia64/sn/kernel/io_init.c
+++ b/arch/ia64/sn/kernel/io_init.c
@@ -271,7 +271,9 @@
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 48528fb..ae838ed 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -1382,6 +1382,10 @@
/* 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 1bf60b1..9eb54b5 100644
--- a/arch/mips/pci/pci.c
+++ b/arch/mips/pci/pci.c
@@ -114,6 +114,7 @@
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 613ca1e..3dfe2d3 100644
--- a/arch/mn10300/unit-asb2305/pci.c
+++ b/arch/mn10300/unit-asb2305/pci.c
@@ -342,6 +342,7 @@
{
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 @@
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 753a567..a2a7391 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -776,8 +776,8 @@
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 1bc09ee..efc1051 100644
--- a/arch/sh/drivers/pci/pci.c
+++ b/arch/sh/drivers/pci/pci.c
@@ -69,6 +69,7 @@
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 899b7203..2971076 100644
--- a/arch/sparc/kernel/leon_pci.c
+++ b/arch/sparc/kernel/leon_pci.c
@@ -40,6 +40,7 @@
/* 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 325df47..9475a74 100644
--- a/arch/tile/kernel/pci.c
+++ b/arch/tile/kernel/pci.c
@@ -339,6 +339,8 @@
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 2c95f37..b1df847 100644
--- a/arch/tile/kernel/pci_gx.c
+++ b/arch/tile/kernel/pci_gx.c
@@ -1030,6 +1030,8 @@
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 3d2612b..95a0ba7 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -490,7 +490,9 @@
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 5b34033..b848cc3 100644
--- a/arch/xtensa/kernel/pci.c
+++ b/arch/xtensa/kernel/pci.c
@@ -174,7 +174,7 @@
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 @@
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);