From: Menglong Dong <dong.menglong@xxxxxxxxxx> [ Upstream commit 1d7ea55668878bb350979c377fc72509dd6f5b21 ] While enqueueing a broadcast skb to port->bc_queue, schedule_work() is called to add port->bc_work, which processes the skbs in bc_queue, to "events" work queue. If port->bc_queue is full, the skb will be discarded and schedule_work(&port->bc_work) won't be called. However, if port->bc_queue is full and port->bc_work is not running or pending, port->bc_queue will keep full and schedule_work() won't be called any more, and all broadcast skbs to macvlan will be discarded. This case can happen: macvlan_process_broadcast() is the pending function of port->bc_work, it moves all the skbs in port->bc_queue to the queue "list", and processes the skbs in "list". During this, new skbs will keep being added to port->bc_queue in macvlan_broadcast_enqueue(), and port->bc_queue may already full when macvlan_process_broadcast() return. This may happen, especially when there are a lot of real-time threads and the process is preempted. Fix this by calling schedule_work(&port->bc_work) even if port->bc_work is full in macvlan_broadcast_enqueue(). Fixes: 412ca1550cbe ("macvlan: Move broadcasts into a work queue") Signed-off-by: Menglong Dong <dong.menglong@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/macvlan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -334,10 +334,11 @@ static void macvlan_broadcast_enqueue(st } spin_unlock(&port->bc_queue.lock); + schedule_work(&port->bc_work); + if (err) goto free_nskb; - schedule_work(&port->bc_work); return; free_nskb: