| From foo@baz Tue 03 Dec 2019 11:07:30 AM CET |
| From: Menglong Dong <dong.menglong@zte.com.cn> |
| Date: Mon, 25 Nov 2019 16:58:09 +0800 |
| Subject: macvlan: schedule bc_work even if error |
| |
| From: Menglong Dong <dong.menglong@zte.com.cn> |
| |
| [ 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@zte.com.cn> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| 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: |
