[PATCH] acpi bridge hotadd: Take the PCI lock when modifying pci bus or device lists

With root bridge and pci bridge hot-plug, new buses and devices can be added
or removed at run time.  Protect the pci bus and device lists with the pci
lock when doing so.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 10 insertions, 1 deletions

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 6186f4d7b119..7d171f83257f 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -374,8 +374,11 @@ struct pci_bus * __devinit pci_add_new_bus(struct pci_bus *parent, struct pci_de
         struct pci_bus *child;
 
         child = pci_alloc_child_bus(parent, dev, busnr);
-        if (child)
+        if (child) {
+                spin_lock(&pci_bus_lock);
                 list_add_tail(&child->node, &parent->children);
+                spin_unlock(&pci_bus_lock);
+        }
         return child;
 }
 
@@ -765,7 +768,9 @@ pci_scan_single_device(struct pci_bus *bus, int devfn)
          * and the bus list for fixup functions, etc.
          */
         INIT_LIST_HEAD(&dev->global_list);
+        spin_lock(&pci_bus_lock);
         list_add_tail(&dev->bus_list, &bus->devices);
+        spin_unlock(&pci_bus_lock);
 
         return dev;
 }
@@ -886,7 +891,9 @@ struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent, int bus,
                 pr_debug("PCI: Bus %04x:%02x already known\n", pci_domain_nr(b), bus);
                 goto err_out;
         }
+        spin_lock(&pci_bus_lock);
         list_add_tail(&b->node, &pci_root_buses);
+        spin_unlock(&pci_bus_lock);
 
         memset(dev, 0, sizeof(*dev));
         dev->parent = parent;
@@ -928,7 +935,9 @@ class_dev_create_file_err:
 class_dev_reg_err:
         device_unregister(dev);
 dev_reg_err:
+        spin_lock(&pci_bus_lock);
         list_del(&b->node);
+        spin_unlock(&pci_bus_lock);
 err_out:
         kfree(dev);
         kfree(b);