PCI: Assign resources before drivers claim devices (pci_scan_bus())

Previously, pci_scan_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_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_bus() and do it after any
resource assignment in the callers.

[bhelgaas: changelog, check for failure in mcf_pci_init()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: Geert Uytterhoeven <geert@linux-m68k.org>
CC: Guan Xuetao <gxt@mprc.pku.edu.cn>
CC: Richard Henderson <rth@twiddle.net>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
CC: Matt Turner <mattst88@gmail.com>
This commit is contained in:
Yijing Wang 2015-03-09 10:33:58 +08:00 committed by Bjorn Helgaas
parent c517d838eb
commit c90570d951
6 changed files with 19 additions and 11 deletions

View File

@ -207,6 +207,9 @@ nautilus_init_pci(void)
/* Scan our single hose. */
bus = pci_scan_bus(0, alpha_mv.pci_ops, hose);
if (!bus)
return;
hose->bus = bus;
pcibios_claim_one_bus(bus);
@ -253,6 +256,7 @@ nautilus_init_pci(void)
for the root bus, so just clear it. */
bus->self = NULL;
pci_fixup_irqs(alpha_mv.pci_swizzle, alpha_mv.pci_map_irq);
pci_bus_add_devices(bus);
}
/*

View File

@ -313,12 +313,16 @@ static int __init mcf_pci_init(void)
schedule_timeout(msecs_to_jiffies(200));
rootbus = pci_scan_bus(0, &mcf_pci_ops, NULL);
if (!rootbus)
return -ENODEV;
rootbus->resource[0] = &mcf_pci_io;
rootbus->resource[1] = &mcf_pci_mem;
pci_fixup_irqs(pci_common_swizzle, mcf_pci_map_irq);
pci_bus_size_bridges(rootbus);
pci_bus_assign_resources(rootbus);
pci_bus_add_devices(rootbus);
return 0;
}

View File

@ -391,12 +391,16 @@ static void __init pcic_pbm_scan_bus(struct linux_pcic *pcic)
struct linux_pbm_info *pbm = &pcic->pbm;
pbm->pci_bus = pci_scan_bus(pbm->pci_first_busno, &pcic_ops, pbm);
if (!pbm->pci_bus)
return;
#if 0 /* deadwood transplanted from sparc64 */
pci_fill_in_pbm_cookies(pbm->pci_bus, pbm, pbm->prom_node);
pci_record_assignments(pbm, pbm->pci_bus);
pci_assign_unassigned(pbm, pbm->pci_bus);
pci_fixup_irq(pbm, pbm->pci_bus);
#endif
pci_bus_add_devices(pbm->pci_bus);
}
/*

View File

@ -266,17 +266,10 @@ static int __init pci_common_init(void)
pci_fixup_irqs(pci_common_swizzle, pci_puv3_map_irq);
if (!pci_has_flag(PCI_PROBE_ONLY)) {
/*
* Size the bridge windows.
*/
pci_bus_size_bridges(puv3_bus);
/*
* Assign resources.
*/
pci_bus_assign_resources(puv3_bus);
}
pci_bus_add_devices(puv3_bus);
return 0;
}
subsys_initcall(pci_common_init);

View File

@ -738,7 +738,7 @@ static void ibm_unconfigure_device(struct pci_func *func)
*/
static u8 bus_structure_fixup(u8 busno)
{
struct pci_bus *bus;
struct pci_bus *bus, *b;
struct pci_dev *dev;
u16 l;
@ -765,7 +765,11 @@ static u8 bus_structure_fixup(u8 busno)
(l != 0x0000) && (l != 0xffff)) {
debug("%s - Inside bus_structure_fixup()\n",
__func__);
pci_scan_bus(busno, ibmphp_pci_bus->ops, NULL);
b = pci_scan_bus(busno, ibmphp_pci_bus->ops, NULL);
if (!b)
continue;
pci_bus_add_devices(b);
break;
}
}

View File

@ -2123,7 +2123,6 @@ struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
if (b) {
pci_scan_child_bus(b);
pci_bus_add_devices(b);
} else {
pci_free_resource_list(&resources);
}