net: Fix locking in flush_backlog
Need to take spinlocks when dequeuing from input_pkt_queue in flush_backlog.
Also, flush_backlog can now be called directly from netdev_run_todo.
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev.c b/net/core/dev.c
index a03aab4..5e3dc28 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2766,17 +2766,19 @@
EXPORT_SYMBOL(netif_receive_skb);
/* Network device is going away, flush any packets still pending */
-static void flush_backlog(void *arg)
+static void flush_backlog(struct net_device *dev, int cpu)
{
- struct net_device *dev = arg;
- struct softnet_data *queue = &__get_cpu_var(softnet_data);
+ struct softnet_data *queue = &per_cpu(softnet_data, cpu);
struct sk_buff *skb, *tmp;
+ unsigned long flags;
+ spin_lock_irqsave(&queue->input_pkt_queue.lock, flags);
skb_queue_walk_safe(&queue->input_pkt_queue, skb, tmp)
if (skb->dev == dev) {
__skb_unlink(skb, &queue->input_pkt_queue);
kfree_skb(skb);
}
+ spin_unlock_irqrestore(&queue->input_pkt_queue.lock, flags);
}
static int napi_gro_complete(struct sk_buff *skb)
@@ -5545,6 +5547,7 @@
while (!list_empty(&list)) {
struct net_device *dev
= list_first_entry(&list, struct net_device, todo_list);
+ int i;
list_del(&dev->todo_list);
if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
@@ -5556,7 +5559,8 @@
dev->reg_state = NETREG_UNREGISTERED;
- on_each_cpu(flush_backlog, dev, 1);
+ for_each_online_cpu(i)
+ flush_backlog(dev, i);
netdev_wait_allrefs(dev);