openvswitch: fix vport-netdev unregister

The combination of two commits:
commit 8e4e1713e4
("openvswitch: Simplify datapath locking.")
commit 2537b4dd0a
("openvswitch:: link upper device for port devices")

introduced a bug where upper_dev wasn't unlinked upon
netdev_unregister notification

The following steps:

  modprobe openvswitch
  ovs-dpctl add-dp test
  ip tuntap add dev tap1 mode tap
  ovs-dpctl add-if test tap1
  ip tuntap del dev tap1 mode tap

are causing multiple warnings:

[   62.747557] gre: GRE over IPv4 demultiplexor driver
[   62.749579] openvswitch: Open vSwitch switching datapath
[   62.755087] device test entered promiscuous mode
[   62.765911] device tap1 entered promiscuous mode
[   62.766033] IPv6: ADDRCONF(NETDEV_UP): tap1: link is not ready
[   62.769017] ------------[ cut here ]------------
[   62.769022] WARNING: CPU: 1 PID: 3267 at net/core/dev.c:5501 rollback_registered_many+0x20f/0x240()
[   62.769023] Modules linked in: openvswitch gre vxlan ip_tunnel libcrc32c ip6table_filter ip6_tables ebtable_nat ebtables nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack xt_CHECKSUM iptable_mangle ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc vhost_net macvtap macvlan vhost kvm_intel kvm dm_crypt iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi hid_generic mxm_wmi eeepc_wmi asus_wmi sparse_keymap dm_multipath psmouse serio_raw usbhid hid parport_pc ppdev firewire_ohci lpc_ich firewire_core e1000e crc_itu_t binfmt_misc igb dca ptp pps_core mac_hid wmi lp parport i2o_config i2o_block video
[   62.769051] CPU: 1 PID: 3267 Comm: ip Not tainted 3.12.0-rc3+ #60
[   62.769052] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012
[   62.769053]  0000000000000009 ffff8807f25cbd28 ffffffff8175e575 0000000000000006
[   62.769055]  0000000000000000 ffff8807f25cbd68 ffffffff8105314c ffff8807f25cbd58
[   62.769057]  ffff8807f2634000 ffff8807f25cbdc8 ffff8807f25cbd88 ffff8807f25cbdc8
[   62.769059] Call Trace:
[   62.769062]  [<ffffffff8175e575>] dump_stack+0x55/0x76
[   62.769065]  [<ffffffff8105314c>] warn_slowpath_common+0x8c/0xc0
[   62.769067]  [<ffffffff8105319a>] warn_slowpath_null+0x1a/0x20
[   62.769069]  [<ffffffff8162a04f>] rollback_registered_many+0x20f/0x240
[   62.769071]  [<ffffffff8162a101>] rollback_registered+0x31/0x40
[   62.769073]  [<ffffffff8162a488>] unregister_netdevice_queue+0x58/0x90
[   62.769075]  [<ffffffff8154f900>] __tun_detach+0x140/0x340
[   62.769077]  [<ffffffff8154fb36>] tun_chr_close+0x36/0x60
[   62.769080]  [<ffffffff811bddaf>] __fput+0xff/0x260
[   62.769082]  [<ffffffff811bdf5e>] ____fput+0xe/0x10
[   62.769084]  [<ffffffff8107b515>] task_work_run+0xb5/0xe0
[   62.769087]  [<ffffffff810029b9>] do_notify_resume+0x59/0x80
[   62.769089]  [<ffffffff813a41fe>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[   62.769091]  [<ffffffff81770f5a>] int_signal+0x12/0x17
[   62.769093] ---[ end trace 838756c62e156ffb ]---
[   62.769481] ------------[ cut here ]------------
[   62.769485] WARNING: CPU: 1 PID: 92 at fs/sysfs/inode.c:325 sysfs_hash_and_remove+0xa9/0xb0()
[   62.769486] sysfs: can not remove 'master', no directory
[   62.769486] Modules linked in: openvswitch gre vxlan ip_tunnel libcrc32c ip6table_filter ip6_tables ebtable_nat ebtables nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack xt_CHECKSUM iptable_mangle ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc vhost_net macvtap macvlan vhost kvm_intel kvm dm_crypt iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi hid_generic mxm_wmi eeepc_wmi asus_wmi sparse_keymap dm_multipath psmouse serio_raw usbhid hid parport_pc ppdev firewire_ohci lpc_ich firewire_core e1000e crc_itu_t binfmt_misc igb dca ptp pps_core mac_hid wmi lp parport i2o_config i2o_block video
[   62.769514] CPU: 1 PID: 92 Comm: kworker/1:2 Tainted: G        W    3.12.0-rc3+ #60
[   62.769515] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012
[   62.769518] Workqueue: events ovs_dp_notify_wq [openvswitch]
[   62.769519]  0000000000000009 ffff880807ad3ac8 ffffffff8175e575 0000000000000006
[   62.769521]  ffff880807ad3b18 ffff880807ad3b08 ffffffff8105314c ffff880807ad3b28
[   62.769523]  0000000000000000 ffffffff81a87a1f ffff8807f2634000 ffff880037038500
[   62.769525] Call Trace:
[   62.769528]  [<ffffffff8175e575>] dump_stack+0x55/0x76
[   62.769529]  [<ffffffff8105314c>] warn_slowpath_common+0x8c/0xc0
[   62.769531]  [<ffffffff81053236>] warn_slowpath_fmt+0x46/0x50
[   62.769533]  [<ffffffff8123e7e9>] sysfs_hash_and_remove+0xa9/0xb0
[   62.769535]  [<ffffffff81240e96>] sysfs_remove_link+0x26/0x30
[   62.769538]  [<ffffffff81631ef7>] __netdev_adjacent_dev_remove+0xf7/0x150
[   62.769540]  [<ffffffff81632037>] __netdev_adjacent_dev_unlink_lists+0x27/0x50
[   62.769542]  [<ffffffff8163213a>] __netdev_adjacent_dev_unlink_neighbour+0x3a/0x50
[   62.769544]  [<ffffffff8163218d>] netdev_upper_dev_unlink+0x3d/0x140
[   62.769548]  [<ffffffffa033c2db>] netdev_destroy+0x4b/0x80 [openvswitch]
[   62.769550]  [<ffffffffa033b696>] ovs_vport_del+0x46/0x60 [openvswitch]
[   62.769552]  [<ffffffffa0335314>] ovs_dp_detach_port+0x44/0x60 [openvswitch]
[   62.769555]  [<ffffffffa0336574>] ovs_dp_notify_wq+0xb4/0x150 [openvswitch]
[   62.769557]  [<ffffffff81075c28>] process_one_work+0x1d8/0x6a0
[   62.769559]  [<ffffffff81075bc8>] ? process_one_work+0x178/0x6a0
[   62.769562]  [<ffffffff8107659b>] worker_thread+0x11b/0x370
[   62.769564]  [<ffffffff81076480>] ? rescuer_thread+0x350/0x350
[   62.769566]  [<ffffffff8107f44a>] kthread+0xea/0xf0
[   62.769568]  [<ffffffff8107f360>] ? flush_kthread_worker+0x150/0x150
[   62.769570]  [<ffffffff81770bac>] ret_from_fork+0x7c/0xb0
[   62.769572]  [<ffffffff8107f360>] ? flush_kthread_worker+0x150/0x150
[   62.769573] ---[ end trace 838756c62e156ffc ]---
[   62.769574] ------------[ cut here ]------------
[   62.769576] WARNING: CPU: 1 PID: 92 at fs/sysfs/inode.c:325 sysfs_hash_and_remove+0xa9/0xb0()
[   62.769577] sysfs: can not remove 'upper_test', no directory
[   62.769577] Modules linked in: openvswitch gre vxlan ip_tunnel libcrc32c ip6table_filter ip6_tables ebtable_nat ebtables nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack xt_CHECKSUM iptable_mangle ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc vhost_net macvtap macvlan vhost kvm_intel kvm dm_crypt iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi hid_generic mxm_wmi eeepc_wmi asus_wmi sparse_keymap dm_multipath psmouse serio_raw usbhid hid parport_pc ppdev firewire_ohci lpc_ich firewire_core e1000e crc_itu_t binfmt_misc igb dca ptp pps_core mac_hid wmi lp parport i2o_config i2o_block video
[   62.769603] CPU: 1 PID: 92 Comm: kworker/1:2 Tainted: G        W    3.12.0-rc3+ #60
[   62.769604] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012
[   62.769606] Workqueue: events ovs_dp_notify_wq [openvswitch]
[   62.769607]  0000000000000009 ffff880807ad3ac8 ffffffff8175e575 0000000000000006
[   62.769609]  ffff880807ad3b18 ffff880807ad3b08 ffffffff8105314c ffff880807ad3b58
[   62.769611]  0000000000000000 ffff880807ad3bd9 ffff8807f2634000 ffff880037038500
[   62.769613] Call Trace:
[   62.769615]  [<ffffffff8175e575>] dump_stack+0x55/0x76
[   62.769617]  [<ffffffff8105314c>] warn_slowpath_common+0x8c/0xc0
[   62.769619]  [<ffffffff81053236>] warn_slowpath_fmt+0x46/0x50
[   62.769621]  [<ffffffff8123e7e9>] sysfs_hash_and_remove+0xa9/0xb0
[   62.769622]  [<ffffffff81240e96>] sysfs_remove_link+0x26/0x30
[   62.769624]  [<ffffffff81631f22>] __netdev_adjacent_dev_remove+0x122/0x150
[   62.769627]  [<ffffffff81632037>] __netdev_adjacent_dev_unlink_lists+0x27/0x50
[   62.769629]  [<ffffffff8163213a>] __netdev_adjacent_dev_unlink_neighbour+0x3a/0x50
[   62.769631]  [<ffffffff8163218d>] netdev_upper_dev_unlink+0x3d/0x140
[   62.769633]  [<ffffffffa033c2db>] netdev_destroy+0x4b/0x80 [openvswitch]
[   62.769636]  [<ffffffffa033b696>] ovs_vport_del+0x46/0x60 [openvswitch]
[   62.769638]  [<ffffffffa0335314>] ovs_dp_detach_port+0x44/0x60 [openvswitch]
[   62.769640]  [<ffffffffa0336574>] ovs_dp_notify_wq+0xb4/0x150 [openvswitch]
[   62.769642]  [<ffffffff81075c28>] process_one_work+0x1d8/0x6a0
[   62.769644]  [<ffffffff81075bc8>] ? process_one_work+0x178/0x6a0
[   62.769646]  [<ffffffff8107659b>] worker_thread+0x11b/0x370
[   62.769648]  [<ffffffff81076480>] ? rescuer_thread+0x350/0x350
[   62.769650]  [<ffffffff8107f44a>] kthread+0xea/0xf0
[   62.769652]  [<ffffffff8107f360>] ? flush_kthread_worker+0x150/0x150
[   62.769654]  [<ffffffff81770bac>] ret_from_fork+0x7c/0xb0
[   62.769656]  [<ffffffff8107f360>] ? flush_kthread_worker+0x150/0x150
[   62.769657] ---[ end trace 838756c62e156ffd ]---
[   62.769724] device tap1 left promiscuous mode

This patch also affects moving devices between net namespaces.

OVS used to ignore netns move notifications which caused problems.
Like:
  ovs-dpctl add-if test tap1
  ip link set tap1 netns 3512
and then removing tap1 inside the namespace will cause hang on missing dev_put.

With this patch OVS will detach dev upon receiving netns move event.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

3 files changed, 19 insertions, 5 deletions

diff --git a/net/openvswitch/dp_notify.c b/net/openvswitch/dp_notify.c
index c3235675f359..5c2dab276109 100644
--- a/net/openvswitch/dp_notify.c
+++ b/net/openvswitch/dp_notify.c
@@ -65,8 +65,7 @@ void ovs_dp_notify_wq(struct work_struct *work)
 					continue;
 
 				netdev_vport = netdev_vport_priv(vport);
-				if (netdev_vport->dev->reg_state == NETREG_UNREGISTERED ||
-				    netdev_vport->dev->reg_state == NETREG_UNREGISTERING)
+				if (!(netdev_vport->dev->priv_flags & IFF_OVS_DATAPATH))
 					dp_detach_port_notify(vport);
 			}
 		}
@@ -88,6 +87,10 @@ static int dp_device_event(struct notifier_block *unused, unsigned long event,
 		return NOTIFY_DONE;
 
 	if (event == NETDEV_UNREGISTER) {
+		/* upper_dev_unlink and decrement promisc immediately */
+		ovs_netdev_detach_dev(vport);
+
+		/* schedule vport destroy, dev_put and genl notification */
 		ovs_net = net_generic(dev_net(dev), ovs_net_id);
 		queue_work(system_wq, &ovs_net->dp_notify_work);
 	}
diff --git a/net/openvswitch/vport-netdev.c b/net/openvswitch/vport-netdev.c
index 09d93c13cfd6..d21f77d875ba 100644
--- a/net/openvswitch/vport-netdev.c
+++ b/net/openvswitch/vport-netdev.c
@@ -150,15 +150,25 @@ static void free_port_rcu(struct rcu_head *rcu)
 	ovs_vport_free(vport_from_priv(netdev_vport));
 }
 
-static void netdev_destroy(struct vport *vport)
+void ovs_netdev_detach_dev(struct vport *vport)
 {
 	struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
 
-	rtnl_lock();
+	ASSERT_RTNL();
 	netdev_vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
 	netdev_rx_handler_unregister(netdev_vport->dev);
-	netdev_upper_dev_unlink(netdev_vport->dev, get_dpdev(vport->dp));
+	netdev_upper_dev_unlink(netdev_vport->dev,
+				netdev_master_upper_dev_get(netdev_vport->dev));
 	dev_set_promiscuity(netdev_vport->dev, -1);
+}
+
+static void netdev_destroy(struct vport *vport)
+{
+	struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
+
+	rtnl_lock();
+	if (netdev_vport->dev->priv_flags & IFF_OVS_DATAPATH)
+		ovs_netdev_detach_dev(vport);
 	rtnl_unlock();
 
 	call_rcu(&netdev_vport->rcu, free_port_rcu);
diff --git a/net/openvswitch/vport-netdev.h b/net/openvswitch/vport-netdev.h
index dd298b5c5cdb..8df01c1127e5 100644
--- a/net/openvswitch/vport-netdev.h
+++ b/net/openvswitch/vport-netdev.h
@@ -39,5 +39,6 @@ netdev_vport_priv(const struct vport *vport)
 }
 
 const char *ovs_netdev_get_name(const struct vport *);
+void ovs_netdev_detach_dev(struct vport *);
 
 #endif /* vport_netdev.h */