1 files changed, 15 insertions, 2 deletions

diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index c84b65920d1b..b1721d71c27c 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -815,9 +815,17 @@ static bool some_qdisc_is_busy(struct net_device *dev)
         return false;
 }
 
+/**
+ *      dev_deactivate_many - deactivate transmissions on several devices
+ *      @head: list of devices to deactivate
+ *
+ *      This function returns only when all outstanding transmissions
+ *      have completed, unless all devices are in dismantle phase.
+ */
 void dev_deactivate_many(struct list_head *head)
 {
         struct net_device *dev;
+        bool sync_needed = false;
 
         list_for_each_entry(dev, head, unreg_list) {
                 netdev_for_each_tx_queue(dev, dev_deactivate_queue,
@@ -827,10 +835,15 @@ void dev_deactivate_many(struct list_head *head)
                                              &noop_qdisc);
 
                 dev_watchdog_down(dev);
+                sync_needed |= !dev->dismantle;
         }
 
-        /* Wait for outstanding qdisc-less dev_queue_xmit calls. */
-        synchronize_rcu();
+        /* Wait for outstanding qdisc-less dev_queue_xmit calls.
+         * This is avoided if all devices are in dismantle phase :
+         * Caller will call synchronize_net() for us
+         */
+        if (sync_needed)
+                synchronize_net();
 
         /* Wait for outstanding qdisc_run calls. */
         list_for_each_entry(dev, head, unreg_list)