PCI: Hold pci_slot_mutex while searching bus->slots list

Previously, pci_setup_device() and similar functions searched the
pci_bus->slots list without any locking.  It was possible for another
thread to update the list while we searched it.

Add pci_dev_assign_slot() to search the list while holding pci_slot_mutex.

[bhelgaas: changelog, fold in CONFIG_SYSFS fix]
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Yijing Wang 2015-07-17 17:16:32 +08:00 committed by Bjorn Helgaas
parent 6754676297
commit 017ffe64e8
5 changed files with 19 additions and 15 deletions

View File

@ -126,7 +126,6 @@ struct pci_dev *of_create_pci_dev(struct device_node *node,
{
struct pci_dev *dev;
const char *type;
struct pci_slot *slot;
dev = pci_alloc_dev(bus);
if (!dev)
@ -145,10 +144,7 @@ struct pci_dev *of_create_pci_dev(struct device_node *node,
dev->needs_freset = 0; /* pcie fundamental reset required */
set_pcie_port_type(dev);
list_for_each_entry(slot, &dev->bus->slots, list)
if (PCI_SLOT(dev->devfn) == slot->number)
dev->slot = slot;
pci_dev_assign_slot(dev);
dev->vendor = get_int_prop(node, "vendor-id", 0xffff);
dev->device = get_int_prop(node, "device-id", 0xffff);
dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0);

View File

@ -249,7 +249,6 @@ static struct pci_dev *of_create_pci_dev(struct pci_pbm_info *pbm,
struct pci_bus *bus, int devfn)
{
struct dev_archdata *sd;
struct pci_slot *slot;
struct platform_device *op;
struct pci_dev *dev;
const char *type;
@ -290,10 +289,7 @@ static struct pci_dev *of_create_pci_dev(struct pci_pbm_info *pbm,
dev->multifunction = 0; /* maybe a lie? */
set_pcie_port_type(dev);
list_for_each_entry(slot, &dev->bus->slots, list)
if (PCI_SLOT(dev->devfn) == slot->number)
dev->slot = slot;
pci_dev_assign_slot(dev);
dev->vendor = of_getintprop_default(node, "vendor-id", 0xffff);
dev->device = of_getintprop_default(node, "device-id", 0xffff);
dev->subsystem_vendor =

View File

@ -1133,7 +1133,6 @@ int pci_setup_device(struct pci_dev *dev)
{
u32 class;
u8 hdr_type;
struct pci_slot *slot;
int pos = 0;
struct pci_bus_region region;
struct resource *res;
@ -1149,10 +1148,7 @@ int pci_setup_device(struct pci_dev *dev)
dev->error_state = pci_channel_io_normal;
set_pcie_port_type(dev);
list_for_each_entry(slot, &dev->bus->slots, list)
if (PCI_SLOT(dev->devfn) == slot->number)
dev->slot = slot;
pci_dev_assign_slot(dev);
/* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
set this higher, assuming the system even supports it. */
dev->dma_mask = 0xffffffff;

View File

@ -194,6 +194,17 @@ static int rename_slot(struct pci_slot *slot, const char *name)
return result;
}
void pci_dev_assign_slot(struct pci_dev *dev)
{
struct pci_slot *slot;
mutex_lock(&pci_slot_mutex);
list_for_each_entry(slot, &dev->bus->slots, list)
if (PCI_SLOT(dev->devfn) == slot->number)
dev->slot = slot;
mutex_unlock(&pci_slot_mutex);
}
static struct pci_slot *get_slot(struct pci_bus *parent, int slot_nr)
{
struct pci_slot *slot;

View File

@ -798,6 +798,11 @@ struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
const char *name,
struct hotplug_slot *hotplug);
void pci_destroy_slot(struct pci_slot *slot);
#ifdef CONFIG_SYSFS
void pci_dev_assign_slot(struct pci_dev *dev);
#else
static inline void pci_dev_assign_slot(struct pci_dev *dev) { }
#endif
int pci_scan_slot(struct pci_bus *bus, int devfn);
struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn);
void pci_device_add(struct pci_dev *dev, struct pci_bus *bus);