When PCI hotplug event happens, the ACPI<->PCI binding relationship should be
updated. Otherwise the binding relationship may become stale and cause invalid
data access or wrong searching results. For example, thinking about following
sequences:
1. Function acpi_pci_bind() installs an ACPI PME event hanlder for the original
PCI device (orig_device).
2. The orignal PCI device is replaced by a new PCI device, so orig_device
destroyed and a new_device created.
3. The new PCI device triggers an ACPI PME event.
4. The registered PME event handle pci_acpi_wake_dev() still tries to access
the orig_device, which may have already been released now.
5. Invalid memory access or event memory corruption.
The solution here is to update the binding relationship when PCI hotplug
event happens.
Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx>
---
drivers/acpi/pci_bind.c | 115 +++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 115 insertions(+), 0 deletions(-)
diff --git a/drivers/acpi/pci_bind.c b/drivers/acpi/pci_bind.c
index 2ef0409..1dd6379 100644
--- a/drivers/acpi/pci_bind.c
+++ b/drivers/acpi/pci_bind.c
@@ -118,3 +118,118 @@ int acpi_pci_bind_root(struct acpi_device *device)
return 0;
}
+
+static struct acpi_device *
+acpi_pci_bind_notify_check(struct pci_dev *pci_dev)
+{
+ acpi_handle handle;
+ struct acpi_device *device;
+
+ handle = DEVICE_ACPI_HANDLE(&pci_dev->dev);
+ if (handle == NULL || acpi_bus_get_device(handle, &device))
+ return NULL;
+
+ if (device && device->parent && device->parent->ops.bind)
+ return device;
+
+ return NULL;
+}
+
+static void acpi_pci_bind_notify_dev_add(struct pci_dev *pci_dev)
+{
+ struct acpi_device *device;
+
+ device = acpi_pci_bind_notify_check(pci_dev);
+ if (device) {
+ pci_acpi_add_pm_notifier(device, pci_dev);
+ if (device->wakeup.flags.run_wake)
+ device_set_run_wake(&pci_dev->dev, true);
+ }
+}
+
+static void acpi_pci_bind_notify_dev_remove(struct pci_dev *pci_dev)
+{
+ struct acpi_device *device;
+
+ device = acpi_pci_bind_notify_check(pci_dev);
+ if (device) {
+ device_set_run_wake(&pci_dev->dev, false);
+ pci_acpi_remove_pm_notifier(device);
+ }
+}
+
+static void acpi_pci_bind_notify_bus_add(struct pci_bus *bus)
+{
+ acpi_handle handle;
+ struct acpi_device *device;
+
+ /* Skip root buses */
+ if (!bus->self)
+ return;
+
+ device = acpi_pci_bind_notify_check(bus->self);
+ if (device) {
+ /*
+ * Install the 'bind' function to facilitate callbacks for
+ * children of the P2P bridge.
+ */
+ device->ops.bind = acpi_pci_bind;
+ device->ops.unbind = acpi_pci_unbind;
+
+ /* Evaluate and parse _PRT, if exists. */
+ if (ACPI_SUCCESS(acpi_get_handle(device->handle,
+ METHOD_NAME__PRT, &handle)))
+ acpi_pci_irq_add_prt(device->handle, bus);
+ }
+}
+
+static void acpi_pci_bind_notify_bus_remove(struct pci_bus *bus)
+{
+ struct acpi_device *device;
+
+ /* Skip root buses */
+ if (!bus->self)
+ return;
+
+ device = acpi_pci_bind_notify_check(bus->self);
+ if (device) {
+ acpi_pci_irq_del_prt(bus);
+
+ device->ops.bind = NULL;
+ device->ops.unbind = NULL;
+ }
+}
+
+static int acpi_pci_bind_notify_fn(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ switch (event) {
+ case PCI_HP_EVENT_DEV_ADD:
+ acpi_pci_bind_notify_dev_add(data);
+ break;
+ case PCI_HP_EVENT_DEV_REMOVE:
+ acpi_pci_bind_notify_dev_remove(data);
+ break;
+ case PCI_HP_EVENT_BUS_ADD:
+ acpi_pci_bind_notify_bus_add(data);
+ break;
+ case PCI_HP_EVENT_BUS_REMOVE:
+ acpi_pci_bind_notify_bus_remove(data);
+ break;
+ default:
+ return NOTIFY_DONE;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block acpi_pci_bind_notifier = {
+ .notifier_call = &acpi_pci_bind_notify_fn,
+};
+
+static int __init acpi_pci_bind_init(void)
+{
+ return pci_register_hotplug_notifier(&acpi_pci_bind_notifier);
+}
+
+subsys_initcall(acpi_pci_bind_init);
--
1.7.5.4
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