firewire: Iterate through units in a keventd callback for update callbacks.

We can't take the klist lock for the child device list in interrupt
context.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 14 insertions, 3 deletions

diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
index e8f2dc3151bd..5599265da4a6 100644
--- a/drivers/firewire/fw-device.c
+++ b/drivers/firewire/fw-device.c
@@ -530,6 +530,14 @@ static int update_unit(struct device *dev, void *data)
         return 0;
 }
 
+static void fw_device_update(struct work_struct *work)
+{
+        struct fw_device *device =
+                container_of(work, struct fw_device, work.work);
+
+        device_for_each_child(&device->device, NULL, update_unit);
+}
+
 void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 {
         struct fw_device *device;
@@ -577,7 +585,10 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
                 device = node->data;
                 device->node_id = node->node_id;
                 device->generation = card->generation;
-                device_for_each_child(&device->device, NULL, update_unit);
+                if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
+                        PREPARE_DELAYED_WORK(&device->work, fw_device_update);
+                        schedule_delayed_work(&device->work, 0);
+                }
                 break;
 
         case FW_NODE_DESTROYED:
@@ -597,8 +608,8 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
                  * to create the device. */
                 device = node->data;
                 if (atomic_xchg(&device->state,
-                         FW_DEVICE_SHUTDOWN) == FW_DEVICE_RUNNING) {
-                        INIT_DELAYED_WORK(&device->work, fw_device_shutdown);
+                                FW_DEVICE_SHUTDOWN) == FW_DEVICE_RUNNING) {
+                        PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown);
                         schedule_delayed_work(&device->work, 0);
                 }
                 break;