ath6kl: Fix lockdep warning

The following is the lockdep warning which detects possible
deadlock condition with the way ar->lock and ar->list_lock
are being used.

  (&(&ar->lock)->rlock){+.-...}, at: [<ffffffffa0492d13>] ath6kl_indicate_tx_activity+0x83/0x110 [ath6kl]
 but this lock took another, SOFTIRQ-unsafe lock in the past:
  (&(&ar->list_lock)->rlock){+.+...}

 and interrupts could create inverse lock ordering between them.

 other info that might help us debug this:
  Possible interrupt unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&(&ar->list_lock)->rlock);
                                local_irq_disable();
                                lock(&(&ar->lock)->rlock);
                                lock(&(&ar->list_lock)->rlock);
   <Interrupt>
     lock(&(&ar->lock)->rlock);

  *** DEADLOCK ***

softirqs have to be disabled when acquiring ar->list_lock to avoid
the above deadlock condition. When the above warning printed the
interface is still up and running without issue.

Reported-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/net/wireless/ath/ath6kl/init.c b/drivers/net/wireless/ath/ath6kl/init.c
index 83b4f165eebf..bb2254d3b439 100644
--- a/drivers/net/wireless/ath/ath6kl/init.c
+++ b/drivers/net/wireless/ath/ath6kl/init.c
@@ -1685,17 +1685,17 @@ void ath6kl_stop_txrx(struct ath6kl *ar)
 		return;
 	}
 
-	spin_lock(&ar->list_lock);
+	spin_lock_bh(&ar->list_lock);
 	list_for_each_entry_safe(vif, tmp_vif, &ar->vif_list, list) {
 		list_del(&vif->list);
-		spin_unlock(&ar->list_lock);
+		spin_unlock_bh(&ar->list_lock);
 		ath6kl_cleanup_vif(vif, test_bit(WMI_READY, &ar->flag));
 		rtnl_lock();
 		ath6kl_deinit_if_data(vif);
 		rtnl_unlock();
-		spin_lock(&ar->list_lock);
+		spin_lock_bh(&ar->list_lock);
 	}
-	spin_unlock(&ar->list_lock);
+	spin_unlock_bh(&ar->list_lock);
 
 	clear_bit(WMI_READY, &ar->flag);