aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorFei Li <lifei.shirley@bytedance.com>2019-06-17 21:26:36 +0800
committerDavid S. Miller <davem@davemloft.net>2019-06-18 10:46:52 -0700
commit72b319dc08b4924a29f5e2560ef6d966fa54c429 (patch)
tree5b903ccecff7da043c98ae8242c2e7f86374cdc2
parentd0bae4a0e3d8c5690a885204d7eb2341a5b4884d (diff)
downloadtip-72b319dc08b4924a29f5e2560ef6d966fa54c429.tar.gz
tip-72b319dc08b4924a29f5e2560ef6d966fa54c429.tar.xz
tip-72b319dc08b4924a29f5e2560ef6d966fa54c429.zip
tun: wake up waitqueues after IFF_UP is set
Currently after setting tap0 link up, the tun code wakes tx/rx waited queues up in tun_net_open() when .ndo_open() is called, however the IFF_UP flag has not been set yet. If there's already a wait queue, it would fail to transmit when checking the IFF_UP flag in tun_sendmsg(). Then the saving vhost_poll_start() will add the wq into wqh until it is waken up again. Although this works when IFF_UP flag has been set when tun_chr_poll detects; this is not true if IFF_UP flag has not been set at that time. Sadly the latter case is a fatal error, as the wq will never be waken up in future unless later manually setting link up on purpose. Fix this by moving the wakeup process into the NETDEV_UP event notifying process, this makes sure IFF_UP has been set before all waited queues been waken up. Signed-off-by: Fei Li <lifei.shirley@bytedance.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/net/tun.c19
1 files changed, 9 insertions, 10 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index c452d6d831dd..d7c55e0fa8f4 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1014,18 +1014,8 @@ static void tun_net_uninit(struct net_device *dev)
/* Net device open. */
static int tun_net_open(struct net_device *dev)
{
- struct tun_struct *tun = netdev_priv(dev);
- int i;
-
netif_tx_start_all_queues(dev);
- for (i = 0; i < tun->numqueues; i++) {
- struct tun_file *tfile;
-
- tfile = rtnl_dereference(tun->tfiles[i]);
- tfile->socket.sk->sk_write_space(tfile->socket.sk);
- }
-
return 0;
}
@@ -3634,6 +3624,7 @@ static int tun_device_event(struct notifier_block *unused,
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct tun_struct *tun = netdev_priv(dev);
+ int i;
if (dev->rtnl_link_ops != &tun_link_ops)
return NOTIFY_DONE;
@@ -3643,6 +3634,14 @@ static int tun_device_event(struct notifier_block *unused,
if (tun_queue_resize(tun))
return NOTIFY_BAD;
break;
+ case NETDEV_UP:
+ for (i = 0; i < tun->numqueues; i++) {
+ struct tun_file *tfile;
+
+ tfile = rtnl_dereference(tun->tfiles[i]);
+ tfile->socket.sk->sk_write_space(tfile->socket.sk);
+ }
+ break;
default:
break;
}