[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>

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 6186f4d7b1192fc65bd0a7d9fde2357c883f0cc9..7d171f83257f0957a11f3806d097a314242dfb80 100644 (file)
--- 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);