From c38383530fb5e160b739aff4bf08c1cc2dfcc659 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Wed, 9 Dec 2015 23:23:56 +0100 Subject: [PATCH] mac802154: tx: fix synced xmit deadlock This patch reverts 6001d52 ("mac802154: tx: don't allow if down while sync tx"). This has side effects with stop callback which flush the transmit workqueue. The stop callback will wait until the workqueue is flushed and holding the rtnl lock. That means it can happen that the stop callback waits forever because it try to lock the rtnl mutex which is already hold by stop callback. Cc: Michael Hennerich Signed-off-by: Alexander Aring Signed-off-by: Marcel Holtmann --- net/mac802154/driver-ops.h | 3 --- net/mac802154/tx.c | 9 --------- 2 files changed, 12 deletions(-) diff --git a/net/mac802154/driver-ops.h b/net/mac802154/driver-ops.h index 0550f3365e33..fd9daf2ecec9 100644 --- a/net/mac802154/driver-ops.h +++ b/net/mac802154/driver-ops.h @@ -18,9 +18,6 @@ drv_xmit_async(struct ieee802154_local *local, struct sk_buff *skb) static inline int drv_xmit_sync(struct ieee802154_local *local, struct sk_buff *skb) { - /* don't allow other operations while sync xmit */ - ASSERT_RTNL(); - might_sleep(); return local->ops->xmit_sync(&local->hw, skb); diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c index 3827f359b336..7e253455f9dd 100644 --- a/net/mac802154/tx.c +++ b/net/mac802154/tx.c @@ -38,12 +38,6 @@ void ieee802154_xmit_worker(struct work_struct *work) struct net_device *dev = skb->dev; int res; - rtnl_lock(); - - /* check if ifdown occurred while schedule */ - if (!netif_running(dev)) - goto err_tx; - res = drv_xmit_sync(local, skb); if (res) goto err_tx; @@ -53,14 +47,11 @@ void ieee802154_xmit_worker(struct work_struct *work) dev->stats.tx_packets++; dev->stats.tx_bytes += skb->len; - rtnl_unlock(); - return; err_tx: /* Restart the netif queue on each sub_if_data object. */ ieee802154_wake_queue(&local->hw); - rtnl_unlock(); kfree_skb(skb); netdev_dbg(dev, "transmission failed\n"); } -- 2.30.2