Bluetooth: Wrong style spin lock used

Use spin_lock_bh() as the code is called from softirq in networking subsystem.
This is needed to prevent deadlocks when 6lowpan link is in use.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 7 insertions, 3 deletions

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index ddf33900f7f3..91995f8ab0a0 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -4661,8 +4661,12 @@ static void hci_queue_acl(struct hci_chan *chan, struct sk_buff_head *queue,
 
                 skb_shinfo(skb)->frag_list = NULL;
 
-                /* Queue all fragments atomically */
-                spin_lock(&queue->lock);
+                /* Queue all fragments atomically. We need to use spin_lock_bh
+                 * here because of 6LoWPAN links, as there this function is
+                 * called from softirq and using normal spin lock could cause
+                 * deadlocks.
+                 */
+                spin_lock_bh(&queue->lock);
 
                 __skb_queue_tail(queue, skb);
 
@@ -4679,7 +4683,7 @@ static void hci_queue_acl(struct hci_chan *chan, struct sk_buff_head *queue,
                         __skb_queue_tail(queue, skb);
                 } while (list);
 
-                spin_unlock(&queue->lock);
+                spin_unlock_bh(&queue->lock);
         }
 }