4 files changed, 21 insertions, 27 deletions

diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
index 420d24fc9388..78648f811049 100644
--- a/drivers/acpi/dock.c
+++ b/drivers/acpi/dock.c
@@ -336,13 +336,9 @@ static struct acpi_device * dock_create_acpi_device(acpi_handle handle)
 static void dock_remove_acpi_device(acpi_handle handle)
 {
         struct acpi_device *device;
-        int ret;
 
-        if (!acpi_bus_get_device(handle, &device)) {
-                ret = acpi_bus_trim(device);
-                if (ret)
-                        pr_debug("error removing bus, %x\n", -ret);
-        }
+        if (!acpi_bus_get_device(handle, &device))
+                acpi_bus_trim(device);
 }
 
 /**
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index b206ce5e1faf..774b17dc7999 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -52,6 +52,7 @@ static const struct acpi_device_id acpi_platform_device_ids[] = {
 
 static LIST_HEAD(acpi_device_list);
 static LIST_HEAD(acpi_bus_id_list);
+static DEFINE_MUTEX(acpi_scan_lock);
 DEFINE_MUTEX(acpi_device_lock);
 LIST_HEAD(acpi_wakeup_device_list);
 
@@ -127,13 +128,8 @@ void acpi_bus_hot_remove_device(void *context)
         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 
-        if (acpi_bus_trim(device)) {
-                printk(KERN_ERR PREFIX
-                                "Removing device failed\n");
-                goto err_out;
-        }
-
-        /* device has been freed */
+        acpi_bus_trim(device);
+        /* Device node has been released. */
         device = NULL;
 
         /* power off device */
@@ -1616,19 +1612,22 @@ static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
 int acpi_bus_scan(acpi_handle handle)
 {
         void *device = NULL;
+        int error = 0;
+
+        mutex_lock(&acpi_scan_lock);
 
         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
                                     acpi_bus_check_add, NULL, NULL, &device);
 
         if (!device)
-                return -ENODEV;
-
-        if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
+                error = -ENODEV;
+        else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
                                     acpi_bus_device_attach, NULL, NULL, NULL);
 
-        return 0;
+        mutex_unlock(&acpi_scan_lock);
+        return error;
 }
 EXPORT_SYMBOL(acpi_bus_scan);
 
@@ -1655,8 +1654,10 @@ static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
         return AE_OK;
 }
 
-int acpi_bus_trim(struct acpi_device *start)
+void acpi_bus_trim(struct acpi_device *start)
 {
+        mutex_lock(&acpi_scan_lock);
+
         /*
          * Execute acpi_bus_device_detach() as a post-order callback to detach
          * all ACPI drivers from the device nodes being removed.
@@ -1671,7 +1672,8 @@ int acpi_bus_trim(struct acpi_device *start)
         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
                             acpi_bus_remove, NULL, NULL);
         acpi_bus_remove(start->handle, 0, NULL, NULL);
-        return 0;
+
+        mutex_unlock(&acpi_scan_lock);
 }
 EXPORT_SYMBOL_GPL(acpi_bus_trim);
 
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 9e2b1f6dbe41..d1a6f4a25da8 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -742,8 +742,7 @@ static int acpiphp_bus_add(struct acpiphp_func *func)
                 /* this shouldn't be in here, so remove
                  * the bus then re-add it...
                  */
-                ret_val = acpi_bus_trim(device);
-                dbg("acpi_bus_trim return %x\n", ret_val);
+                acpi_bus_trim(device);
         }
 
         ret_val = acpi_bus_scan(func->handle);
@@ -772,11 +771,8 @@ static int acpiphp_bus_trim(acpi_handle handle)
                 return retval;
         }
 
-        retval = acpi_bus_trim(device);
-        if (retval)
-                err("cannot remove from acpi list\n");
-
-        return retval;
+        acpi_bus_trim(device);
+        return 0;
 }
 
 static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index fc76b1f7ef06..ad0a86ac5cce 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -386,7 +386,7 @@ int acpi_bus_register_driver(struct acpi_driver *driver);
 void acpi_bus_unregister_driver(struct acpi_driver *driver);
 int acpi_bus_scan(acpi_handle handle);
 void acpi_bus_hot_remove_device(void *context);
-int acpi_bus_trim(struct acpi_device *start);
+void acpi_bus_trim(struct acpi_device *start);
 acpi_status acpi_bus_get_ejd(acpi_handle handle, acpi_handle * ejd);
 int acpi_match_device_ids(struct acpi_device *device,
                           const struct acpi_device_id *ids);