platform / x86: Use global PCI rescan-remove locking

Multiple race conditions are possible between the rfkill hotplug in the
asus-wmi and eeepc-laptop drivers and the generic PCI bus rescan and device
removal that can be triggered via sysfs.

To avoid those race conditions make asus-wmi and eeepc-laptop use global
PCI rescan-remove locking around the rfkill hotplug.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/platform/x86/asus-wmi.c

@@ -606,6 +606,7 @@ static void asus_rfkill_hotplug(struct asus_wmi *asus)
 	mutex_unlock(&asus->wmi_lock);
 
 	mutex_lock(&asus->hotplug_lock);
+	pci_lock_rescan_remove();
 
 	if (asus->wlan.rfkill)
 		rfkill_set_sw_state(asus->wlan.rfkill, blocked);
@@ -656,6 +657,7 @@ static void asus_rfkill_hotplug(struct asus_wmi *asus)
 	}
 
 out_unlock:
+	pci_unlock_rescan_remove();
 	mutex_unlock(&asus->hotplug_lock);
 }
 

drivers/platform/x86/eeepc-laptop.c

@@ -592,6 +592,7 @@ static void eeepc_rfkill_hotplug(struct eeepc_laptop *eeepc, acpi_handle handle)
 		rfkill_set_sw_state(eeepc->wlan_rfkill, blocked);
 
 	mutex_lock(&eeepc->hotplug_lock);
+	pci_lock_rescan_remove();
 
 	if (eeepc->hotplug_slot) {
 		port = acpi_get_pci_dev(handle);
@@ -649,6 +650,7 @@ static void eeepc_rfkill_hotplug(struct eeepc_laptop *eeepc, acpi_handle handle)
 	}
 
 out_unlock:
+	pci_unlock_rescan_remove();
 	mutex_unlock(&eeepc->hotplug_lock);
 }