net: Fix inconsistent teardown and release of private netdev state.

Submitted by David Miller on June 7, 2017, 7:54 p.m.

Details

Message ID 20170607.155411.201795978436906426.davem@davemloft.net
State Accepted
Delegated to: David Miller
Headers show

Commit Message

David Miller June 7, 2017, 7:54 p.m.
Network devices can allocate reasources and private memory using
netdev_ops->ndo_init().  However, the release of these resources
can occur in one of two different places.

Either netdev_ops->ndo_uninit() or netdev->destructor().

The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.

netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.

netdev->destructor(), on the other hand, does not run until the
netdev references all go away.

Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().

This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.

If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit().  But
it is not able to invoke netdev->destructor().

This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.

However, this means that the resources that would normally be released
by netdev->destructor() will not be.

Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.

Many drivers do not try to deal with this, and instead we have leaks.

Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().

netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().

netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().

Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().

And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().

Signed-off-by: David S. Miller <davem@davemloft.net>
---

This is from a few weeks ago, pushed to 'net' and queued up for
-stable.

 drivers/net/bonding/bond_main.c                             | 6 +++---
 drivers/net/caif/caif_hsi.c                                 | 2 +-
 drivers/net/caif/caif_serial.c                              | 2 +-
 drivers/net/caif/caif_spi.c                                 | 2 +-
 drivers/net/caif/caif_virtio.c                              | 2 +-
 drivers/net/can/slcan.c                                     | 7 +++----
 drivers/net/can/vcan.c                                      | 2 +-
 drivers/net/can/vxcan.c                                     | 2 +-
 drivers/net/dummy.c                                         | 4 ++--
 drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c             | 2 +-
 drivers/net/geneve.c                                        | 2 +-
 drivers/net/gtp.c                                           | 2 +-
 drivers/net/hamradio/6pack.c                                | 2 +-
 drivers/net/hamradio/bpqether.c                             | 2 +-
 drivers/net/ifb.c                                           | 4 ++--
 drivers/net/ipvlan/ipvlan_main.c                            | 2 +-
 drivers/net/loopback.c                                      | 4 ++--
 drivers/net/macsec.c                                        | 4 ++--
 drivers/net/macvlan.c                                       | 2 +-
 drivers/net/nlmon.c                                         | 2 +-
 drivers/net/slip/slip.c                                     | 7 +++----
 drivers/net/team/team.c                                     | 4 ++--
 drivers/net/tun.c                                           | 4 ++--
 drivers/net/usb/cdc-phonet.c                                | 2 +-
 drivers/net/usb/qmi_wwan.c                                  | 2 +-
 drivers/net/veth.c                                          | 4 ++--
 drivers/net/vrf.c                                           | 2 +-
 drivers/net/vsockmon.c                                      | 2 +-
 drivers/net/vxlan.c                                         | 2 +-
 drivers/net/wan/dlci.c                                      | 2 +-
 drivers/net/wan/hdlc_fr.c                                   | 2 +-
 drivers/net/wan/lapbether.c                                 | 2 +-
 drivers/net/wireless/ath/ath6kl/main.c                      | 2 +-
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 1 -
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c     | 3 ++-
 drivers/net/wireless/intersil/hostap/hostap_main.c          | 2 +-
 drivers/net/wireless/mac80211_hwsim.c                       | 2 +-
 drivers/net/wireless/marvell/mwifiex/main.c                 | 2 +-
 drivers/staging/rtl8188eu/os_dep/mon.c                      | 2 +-
 drivers/usb/gadget/function/f_phonet.c                      | 2 +-
 include/linux/netdevice.h                                   | 7 ++++---
 net/8021q/vlan_dev.c                                        | 4 ++--
 net/batman-adv/soft-interface.c                             | 5 ++---
 net/bluetooth/6lowpan.c                                     | 2 +-
 net/bridge/br_device.c                                      | 2 +-
 net/caif/chnl_net.c                                         | 4 ++--
 net/core/dev.c                                              | 8 ++++++--
 net/hsr/hsr_device.c                                        | 4 ++--
 net/ieee802154/6lowpan/core.c                               | 2 +-
 net/ipv4/ip_tunnel.c                                        | 4 ++--
 net/ipv4/ipmr.c                                             | 2 +-
 net/ipv6/ip6_gre.c                                          | 9 +++++----
 net/ipv6/ip6_tunnel.c                                       | 8 ++++----
 net/ipv6/ip6_vti.c                                          | 8 ++++----
 net/ipv6/ip6mr.c                                            | 2 +-
 net/ipv6/sit.c                                              | 6 +++---
 net/irda/irlan/irlan_eth.c                                  | 2 +-
 net/l2tp/l2tp_eth.c                                         | 2 +-
 net/mac80211/iface.c                                        | 6 +++---
 net/mac802154/iface.c                                       | 7 +++----
 net/openvswitch/vport-internal_dev.c                        | 4 ++--
 net/phonet/pep-gprs.c                                       | 2 +-
 62 files changed, 105 insertions(+), 103 deletions(-)

Comments

stephen hemminger June 9, 2017, 5:21 p.m.
On Wed, 07 Jun 2017 15:54:11 -0400 (EDT)
David Miller <davem@davemloft.net> wrote:

> Network devices can allocate reasources and private memory using
> netdev_ops->ndo_init().  However, the release of these resources
> can occur in one of two different places.
> 
> Either netdev_ops->ndo_uninit() or netdev->destructor().
> 
> The decision of which operation frees the resources depends upon
> whether it is necessary for all netdev refs to be released before it
> is safe to perform the freeing.
> 
> netdev_ops->ndo_uninit() presumably can occur right after the
> NETDEV_UNREGISTER notifier completes and the unicast and multicast
> address lists are flushed.
> 
> netdev->destructor(), on the other hand, does not run until the
> netdev references all go away.
> 
> Further complicating the situation is that netdev->destructor()
> almost universally does also a free_netdev().
> 
> This creates a problem for the logic in register_netdevice().
> Because all callers of register_netdevice() manage the freeing
> of the netdev, and invoke free_netdev(dev) if register_netdevice()
> fails.
> 
> If netdev_ops->ndo_init() succeeds, but something else fails inside
> of register_netdevice(), it does call ndo_ops->ndo_uninit().  But
> it is not able to invoke netdev->destructor().
> 
> This is because netdev->destructor() will do a free_netdev() and
> then the caller of register_netdevice() will do the same.
> 
> However, this means that the resources that would normally be released
> by netdev->destructor() will not be.
> 
> Over the years drivers have added local hacks to deal with this, by
> invoking their destructor parts by hand when register_netdevice()
> fails.
> 
> Many drivers do not try to deal with this, and instead we have leaks.
> 
> Let's close this hole by formalizing the distinction between what
> private things need to be freed up by netdev->destructor() and whether
> the driver needs unregister_netdevice() to perform the free_netdev().
> 
> netdev->priv_destructor() performs all actions to free up the private
> resources that used to be freed by netdev->destructor(), except for
> free_netdev().
> 
> netdev->needs_free_netdev is a boolean that indicates whether
> free_netdev() should be done at the end of unregister_netdevice().
> 
> Now, register_netdevice() can sanely release all resources after
> ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
> and netdev->priv_destructor().
> 
> And at the end of unregister_netdevice(), we invoke
> netdev->priv_destructor() and optionally call free_netdev().
> 
> Signed-off-by: David S. Miller <davem@davemloft.net>
> ---
> 
> This is from a few weeks ago, pushed to 'net' and queued up for
> -stable.
> 
>  drivers/net/bonding/bond_main.c                             | 6 +++---
>  drivers/net/caif/caif_hsi.c                                 | 2 +-
>  drivers/net/caif/caif_serial.c                              | 2 +-
>  drivers/net/caif/caif_spi.c                                 | 2 +-
>  drivers/net/caif/caif_virtio.c                              | 2 +-
>  drivers/net/can/slcan.c                                     | 7 +++----
>  drivers/net/can/vcan.c                                      | 2 +-
>  drivers/net/can/vxcan.c                                     | 2 +-
>  drivers/net/dummy.c                                         | 4 ++--
>  drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c             | 2 +-
>  drivers/net/geneve.c                                        | 2 +-
>  drivers/net/gtp.c                                           | 2 +-
>  drivers/net/hamradio/6pack.c                                | 2 +-
>  drivers/net/hamradio/bpqether.c                             | 2 +-
>  drivers/net/ifb.c                                           | 4 ++--
>  drivers/net/ipvlan/ipvlan_main.c                            | 2 +-
>  drivers/net/loopback.c                                      | 4 ++--
>  drivers/net/macsec.c                                        | 4 ++--
>  drivers/net/macvlan.c                                       | 2 +-
>  drivers/net/nlmon.c                                         | 2 +-
>  drivers/net/slip/slip.c                                     | 7 +++----
>  drivers/net/team/team.c                                     | 4 ++--
>  drivers/net/tun.c                                           | 4 ++--
>  drivers/net/usb/cdc-phonet.c                                | 2 +-
>  drivers/net/usb/qmi_wwan.c                                  | 2 +-
>  drivers/net/veth.c                                          | 4 ++--
>  drivers/net/vrf.c                                           | 2 +-
>  drivers/net/vsockmon.c                                      | 2 +-
>  drivers/net/vxlan.c                                         | 2 +-
>  drivers/net/wan/dlci.c                                      | 2 +-
>  drivers/net/wan/hdlc_fr.c                                   | 2 +-
>  drivers/net/wan/lapbether.c                                 | 2 +-
>  drivers/net/wireless/ath/ath6kl/main.c                      | 2 +-
>  drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 1 -
>  drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c     | 3 ++-
>  drivers/net/wireless/intersil/hostap/hostap_main.c          | 2 +-
>  drivers/net/wireless/mac80211_hwsim.c                       | 2 +-
>  drivers/net/wireless/marvell/mwifiex/main.c                 | 2 +-
>  drivers/staging/rtl8188eu/os_dep/mon.c                      | 2 +-
>  drivers/usb/gadget/function/f_phonet.c                      | 2 +-
>  include/linux/netdevice.h                                   | 7 ++++---
>  net/8021q/vlan_dev.c                                        | 4 ++--
>  net/batman-adv/soft-interface.c                             | 5 ++---
>  net/bluetooth/6lowpan.c                                     | 2 +-
>  net/bridge/br_device.c                                      | 2 +-
>  net/caif/chnl_net.c                                         | 4 ++--
>  net/core/dev.c                                              | 8 ++++++--
>  net/hsr/hsr_device.c                                        | 4 ++--
>  net/ieee802154/6lowpan/core.c                               | 2 +-
>  net/ipv4/ip_tunnel.c                                        | 4 ++--
>  net/ipv4/ipmr.c                                             | 2 +-
>  net/ipv6/ip6_gre.c                                          | 9 +++++----
>  net/ipv6/ip6_tunnel.c                                       | 8 ++++----
>  net/ipv6/ip6_vti.c                                          | 8 ++++----
>  net/ipv6/ip6mr.c                                            | 2 +-
>  net/ipv6/sit.c                                              | 6 +++---
>  net/irda/irlan/irlan_eth.c                                  | 2 +-
>  net/l2tp/l2tp_eth.c                                         | 2 +-
>  net/mac80211/iface.c                                        | 6 +++---
>  net/mac802154/iface.c                                       | 7 +++----
>  net/openvswitch/vport-internal_dev.c                        | 4 ++--
>  net/phonet/pep-gprs.c                                       | 2 +-
>  62 files changed, 105 insertions(+), 103 deletions(-)

Is there anything in Documentation/networking/netdevices.txt about this to
avoid any future issues?
David Miller June 9, 2017, 6:54 p.m.
From: Stephen Hemminger <stephen@networkplumber.org>
Date: Fri, 9 Jun 2017 10:21:04 -0700

> Is there anything in Documentation/networking/netdevices.txt about this to
> avoid any future issues?

You asked me about this last time, and I did not forget about it.

I sincerely lack the time to do a writeup about it, and I felt that
delaying the fix for another week or two until I find that magical
non-existing timeframe to write the docs was not beneficial for
users at all.
stephen hemminger June 12, 2017, 8:40 p.m.
On Fri, 09 Jun 2017 14:54:34 -0400 (EDT)
David Miller <davem@davemloft.net> wrote:

> From: Stephen Hemminger <stephen@networkplumber.org>
> Date: Fri, 9 Jun 2017 10:21:04 -0700
> 
> > Is there anything in Documentation/networking/netdevices.txt about this to
> > avoid any future issues?  
> 
> You asked me about this last time, and I did not forget about it.
> 
> I sincerely lack the time to do a writeup about it, and I felt that
> delaying the fix for another week or two until I find that magical
> non-existing timeframe to write the docs was not beneficial for
> users at all.

I could take a stab at it, but my writing skills are not great.
We don't need to delay for Documentation, in fact it is easier to write after
the cleanup.

Patch hide | download patch | download mbox

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 2be7880..d507b68 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4185,7 +4185,6 @@  static void bond_destructor(struct net_device *bond_dev)
 	struct bonding *bond = netdev_priv(bond_dev);
 	if (bond->wq)
 		destroy_workqueue(bond->wq);
-	free_netdev(bond_dev);
 }
 
 void bond_setup(struct net_device *bond_dev)
@@ -4205,7 +4204,8 @@  void bond_setup(struct net_device *bond_dev)
 	bond_dev->netdev_ops = &bond_netdev_ops;
 	bond_dev->ethtool_ops = &bond_ethtool_ops;
 
-	bond_dev->destructor = bond_destructor;
+	bond_dev->needs_free_netdev = true;
+	bond_dev->priv_destructor = bond_destructor;
 
 	SET_NETDEV_DEVTYPE(bond_dev, &bond_type);
 
@@ -4730,7 +4730,7 @@  int bond_create(struct net *net, const char *name)
 
 	rtnl_unlock();
 	if (res < 0)
-		bond_destructor(bond_dev);
+		free_netdev(bond_dev);
 	return res;
 }
 
diff --git a/drivers/net/caif/caif_hsi.c b/drivers/net/caif/caif_hsi.c
index ddabce7..71a7c3b 100644
--- a/drivers/net/caif/caif_hsi.c
+++ b/drivers/net/caif/caif_hsi.c
@@ -1121,7 +1121,7 @@  static void cfhsi_setup(struct net_device *dev)
 	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
 	dev->mtu = CFHSI_MAX_CAIF_FRAME_SZ;
 	dev->priv_flags |= IFF_NO_QUEUE;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	dev->netdev_ops = &cfhsi_netdevops;
 	for (i = 0; i < CFHSI_PRIO_LAST; ++i)
 		skb_queue_head_init(&cfhsi->qhead[i]);
diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c
index c2dea49..76e1d35 100644
--- a/drivers/net/caif/caif_serial.c
+++ b/drivers/net/caif/caif_serial.c
@@ -428,7 +428,7 @@  static void caifdev_setup(struct net_device *dev)
 	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
 	dev->mtu = CAIF_MAX_MTU;
 	dev->priv_flags |= IFF_NO_QUEUE;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	skb_queue_head_init(&serdev->head);
 	serdev->common.link_select = CAIF_LINK_LOW_LATENCY;
 	serdev->common.use_frag = true;
diff --git a/drivers/net/caif/caif_spi.c b/drivers/net/caif/caif_spi.c
index 3a529fb..fc21afe 100644
--- a/drivers/net/caif/caif_spi.c
+++ b/drivers/net/caif/caif_spi.c
@@ -712,7 +712,7 @@  static void cfspi_setup(struct net_device *dev)
 	dev->flags = IFF_NOARP | IFF_POINTOPOINT;
 	dev->priv_flags |= IFF_NO_QUEUE;
 	dev->mtu = SPI_MAX_PAYLOAD_SIZE;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	skb_queue_head_init(&cfspi->qhead);
 	skb_queue_head_init(&cfspi->chead);
 	cfspi->cfdev.link_select = CAIF_LINK_HIGH_BANDW;
diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c
index bc0eb47..8bffd25 100644
--- a/drivers/net/caif/caif_virtio.c
+++ b/drivers/net/caif/caif_virtio.c
@@ -617,7 +617,7 @@  static void cfv_netdev_setup(struct net_device *netdev)
 	netdev->tx_queue_len = 100;
 	netdev->flags = IFF_POINTOPOINT | IFF_NOARP;
 	netdev->mtu = CFV_DEF_MTU_SIZE;
-	netdev->destructor = free_netdev;
+	netdev->needs_free_netdev = true;
 }
 
 /* Create debugfs counters for the device */
diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index eb71737..6a6e896 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -417,7 +417,7 @@  static int slc_open(struct net_device *dev)
 static void slc_free_netdev(struct net_device *dev)
 {
 	int i = dev->base_addr;
-	free_netdev(dev);
+
 	slcan_devs[i] = NULL;
 }
 
@@ -436,7 +436,8 @@  static const struct net_device_ops slc_netdev_ops = {
 static void slc_setup(struct net_device *dev)
 {
 	dev->netdev_ops		= &slc_netdev_ops;
-	dev->destructor		= slc_free_netdev;
+	dev->needs_free_netdev	= true;
+	dev->priv_destructor	= slc_free_netdev;
 
 	dev->hard_header_len	= 0;
 	dev->addr_len		= 0;
@@ -761,8 +762,6 @@  static void __exit slcan_exit(void)
 		if (sl->tty) {
 			printk(KERN_ERR "%s: tty discipline still running\n",
 			       dev->name);
-			/* Intentionally leak the control block. */
-			dev->destructor = NULL;
 		}
 
 		unregister_netdev(dev);
diff --git a/drivers/net/can/vcan.c b/drivers/net/can/vcan.c
index facca33..0eda1b3 100644
--- a/drivers/net/can/vcan.c
+++ b/drivers/net/can/vcan.c
@@ -163,7 +163,7 @@  static void vcan_setup(struct net_device *dev)
 		dev->flags |= IFF_ECHO;
 
 	dev->netdev_ops		= &vcan_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 }
 
 static struct rtnl_link_ops vcan_link_ops __read_mostly = {
diff --git a/drivers/net/can/vxcan.c b/drivers/net/can/vxcan.c
index 7fbb247..30cf236 100644
--- a/drivers/net/can/vxcan.c
+++ b/drivers/net/can/vxcan.c
@@ -156,7 +156,7 @@  static void vxcan_setup(struct net_device *dev)
 	dev->tx_queue_len	= 0;
 	dev->flags		= (IFF_NOARP|IFF_ECHO);
 	dev->netdev_ops		= &vxcan_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 }
 
 /* forward declaration for rtnl_create_link() */
diff --git a/drivers/net/dummy.c b/drivers/net/dummy.c
index 149244a..9905b52 100644
--- a/drivers/net/dummy.c
+++ b/drivers/net/dummy.c
@@ -328,7 +328,6 @@  static void dummy_free_netdev(struct net_device *dev)
 	struct dummy_priv *priv = netdev_priv(dev);
 
 	kfree(priv->vfinfo);
-	free_netdev(dev);
 }
 
 static void dummy_setup(struct net_device *dev)
@@ -338,7 +337,8 @@  static void dummy_setup(struct net_device *dev)
 	/* Initialize the device structure. */
 	dev->netdev_ops = &dummy_netdev_ops;
 	dev->ethtool_ops = &dummy_ethtool_ops;
-	dev->destructor = dummy_free_netdev;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = dummy_free_netdev;
 
 	/* Fill in device structure with ethernet-generic values. */
 	dev->flags |= IFF_NOARP;
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index c12c4a3..2649a06e 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -4537,7 +4537,7 @@  static void dummy_setup(struct net_device *dev)
 	/* Initialize the device structure. */
 	dev->netdev_ops = &cxgb4_mgmt_netdev_ops;
 	dev->ethtool_ops = &cxgb4_mgmt_ethtool_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 }
 
 static int config_mgmt_dev(struct pci_dev *pdev)
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index dec5d56..4d44c02 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1007,7 +1007,7 @@  static void geneve_setup(struct net_device *dev)
 
 	dev->netdev_ops = &geneve_netdev_ops;
 	dev->ethtool_ops = &geneve_ethtool_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 
 	SET_NETDEV_DEVTYPE(dev, &geneve_type);
 
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 4fea1b3..abb82ff 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -611,7 +611,7 @@  static const struct net_device_ops gtp_netdev_ops = {
 static void gtp_link_setup(struct net_device *dev)
 {
 	dev->netdev_ops		= &gtp_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 
 	dev->hard_header_len = 0;
 	dev->addr_len = 0;
diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c
index 922bf44..021a8ec 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -311,7 +311,7 @@  static void sp_setup(struct net_device *dev)
 {
 	/* Finish setting up the DEVICE info. */
 	dev->netdev_ops		= &sp_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 	dev->mtu		= SIXP_MTU;
 	dev->hard_header_len	= AX25_MAX_HEADER_LEN;
 	dev->header_ops 	= &ax25_header_ops;
diff --git a/drivers/net/hamradio/bpqether.c b/drivers/net/hamradio/bpqether.c
index f62e7f3..78a6414 100644
--- a/drivers/net/hamradio/bpqether.c
+++ b/drivers/net/hamradio/bpqether.c
@@ -476,7 +476,7 @@  static const struct net_device_ops bpq_netdev_ops = {
 static void bpq_setup(struct net_device *dev)
 {
 	dev->netdev_ops	     = &bpq_netdev_ops;
-	dev->destructor	     = free_netdev;
+	dev->needs_free_netdev = true;
 
 	memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
 	memcpy(dev->dev_addr,  &ax25_defaddr, AX25_ADDR_LEN);
diff --git a/drivers/net/ifb.c b/drivers/net/ifb.c
index 312fce7..144ea5a 100644
--- a/drivers/net/ifb.c
+++ b/drivers/net/ifb.c
@@ -207,7 +207,6 @@  static void ifb_dev_free(struct net_device *dev)
 		__skb_queue_purge(&txp->tq);
 	}
 	kfree(dp->tx_private);
-	free_netdev(dev);
 }
 
 static void ifb_setup(struct net_device *dev)
@@ -230,7 +229,8 @@  static void ifb_setup(struct net_device *dev)
 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 	netif_keep_dst(dev);
 	eth_hw_addr_random(dev);
-	dev->destructor = ifb_dev_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = ifb_dev_free;
 }
 
 static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev)
diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c
index 618ed88..7c7680c 100644
--- a/drivers/net/ipvlan/ipvlan_main.c
+++ b/drivers/net/ipvlan/ipvlan_main.c
@@ -632,7 +632,7 @@  void ipvlan_link_setup(struct net_device *dev)
 	dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
 	dev->priv_flags |= IFF_UNICAST_FLT | IFF_NO_QUEUE;
 	dev->netdev_ops = &ipvlan_netdev_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	dev->header_ops = &ipvlan_header_ops;
 	dev->ethtool_ops = &ipvlan_ethtool_ops;
 }
diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index 224f65c..3061249 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -159,7 +159,6 @@  static void loopback_dev_free(struct net_device *dev)
 {
 	dev_net(dev)->loopback_dev = NULL;
 	free_percpu(dev->lstats);
-	free_netdev(dev);
 }
 
 static const struct net_device_ops loopback_ops = {
@@ -196,7 +195,8 @@  static void loopback_setup(struct net_device *dev)
 	dev->ethtool_ops	= &loopback_ethtool_ops;
 	dev->header_ops		= &eth_header_ops;
 	dev->netdev_ops		= &loopback_ops;
-	dev->destructor		= loopback_dev_free;
+	dev->needs_free_netdev	= true;
+	dev->priv_destructor	= loopback_dev_free;
 }
 
 /* Setup and register the loopback device. */
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index cdc347b..7941167 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -2996,7 +2996,6 @@  static void macsec_free_netdev(struct net_device *dev)
 	free_percpu(macsec->secy.tx_sc.stats);
 
 	dev_put(real_dev);
-	free_netdev(dev);
 }
 
 static void macsec_setup(struct net_device *dev)
@@ -3006,7 +3005,8 @@  static void macsec_setup(struct net_device *dev)
 	dev->max_mtu = ETH_MAX_MTU;
 	dev->priv_flags |= IFF_NO_QUEUE;
 	dev->netdev_ops = &macsec_netdev_ops;
-	dev->destructor = macsec_free_netdev;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = macsec_free_netdev;
 	SET_NETDEV_DEVTYPE(dev, &macsec_type);
 
 	eth_zero_addr(dev->broadcast);
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index b34eaaa..b8cec52 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1089,7 +1089,7 @@  void macvlan_common_setup(struct net_device *dev)
 	netif_keep_dst(dev);
 	dev->priv_flags	       |= IFF_UNICAST_FLT;
 	dev->netdev_ops		= &macvlan_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 	dev->header_ops		= &macvlan_hard_header_ops;
 	dev->ethtool_ops	= &macvlan_ethtool_ops;
 }
diff --git a/drivers/net/nlmon.c b/drivers/net/nlmon.c
index b916038..c4b3362 100644
--- a/drivers/net/nlmon.c
+++ b/drivers/net/nlmon.c
@@ -113,7 +113,7 @@  static void nlmon_setup(struct net_device *dev)
 
 	dev->netdev_ops	= &nlmon_ops;
 	dev->ethtool_ops = &nlmon_ethtool_ops;
-	dev->destructor	= free_netdev;
+	dev->needs_free_netdev = true;
 
 	dev->features = NETIF_F_SG | NETIF_F_FRAGLIST |
 			NETIF_F_HIGHDMA | NETIF_F_LLTX;
diff --git a/drivers/net/slip/slip.c b/drivers/net/slip/slip.c
index 1da31dc..74b9072 100644
--- a/drivers/net/slip/slip.c
+++ b/drivers/net/slip/slip.c
@@ -629,7 +629,7 @@  static void sl_uninit(struct net_device *dev)
 static void sl_free_netdev(struct net_device *dev)
 {
 	int i = dev->base_addr;
-	free_netdev(dev);
+
 	slip_devs[i] = NULL;
 }
 
@@ -651,7 +651,8 @@  static const struct net_device_ops sl_netdev_ops = {
 static void sl_setup(struct net_device *dev)
 {
 	dev->netdev_ops		= &sl_netdev_ops;
-	dev->destructor		= sl_free_netdev;
+	dev->needs_free_netdev	= true;
+	dev->priv_destructor	= sl_free_netdev;
 
 	dev->hard_header_len	= 0;
 	dev->addr_len		= 0;
@@ -1369,8 +1370,6 @@  static void __exit slip_exit(void)
 		if (sl->tty) {
 			printk(KERN_ERR "%s: tty discipline still running\n",
 			       dev->name);
-			/* Intentionally leak the control block. */
-			dev->destructor = NULL;
 		}
 
 		unregister_netdev(dev);
diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index 6c5d5ef..fba8c13 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -1643,7 +1643,6 @@  static void team_destructor(struct net_device *dev)
 	struct team *team = netdev_priv(dev);
 
 	free_percpu(team->pcpu_stats);
-	free_netdev(dev);
 }
 
 static int team_open(struct net_device *dev)
@@ -2079,7 +2078,8 @@  static void team_setup(struct net_device *dev)
 
 	dev->netdev_ops = &team_netdev_ops;
 	dev->ethtool_ops = &team_ethtool_ops;
-	dev->destructor	= team_destructor;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = team_destructor;
 	dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
 	dev->priv_flags |= IFF_NO_QUEUE;
 	dev->priv_flags |= IFF_TEAM;
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index bbd707b..9ee7d42 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1560,7 +1560,6 @@  static void tun_free_netdev(struct net_device *dev)
 	free_percpu(tun->pcpu_stats);
 	tun_flow_uninit(tun);
 	security_tun_dev_free_security(tun->security);
-	free_netdev(dev);
 }
 
 static void tun_setup(struct net_device *dev)
@@ -1571,7 +1570,8 @@  static void tun_setup(struct net_device *dev)
 	tun->group = INVALID_GID;
 
 	dev->ethtool_ops = &tun_ethtool_ops;
-	dev->destructor = tun_free_netdev;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = tun_free_netdev;
 	/* We prefer our own queue length */
 	dev->tx_queue_len = TUN_READQ_SIZE;
 }
diff --git a/drivers/net/usb/cdc-phonet.c b/drivers/net/usb/cdc-phonet.c
index eb52de8..c7a350b 100644
--- a/drivers/net/usb/cdc-phonet.c
+++ b/drivers/net/usb/cdc-phonet.c
@@ -298,7 +298,7 @@  static void usbpn_setup(struct net_device *dev)
 	dev->addr_len		= 1;
 	dev->tx_queue_len	= 3;
 
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 }
 
 /*
diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index d716576..e76f988 100644
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -123,7 +123,7 @@  static void qmimux_setup(struct net_device *dev)
 	dev->addr_len        = 0;
 	dev->flags           = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 	dev->netdev_ops      = &qmimux_netdev_ops;
-	dev->destructor      = free_netdev;
+	dev->needs_free_netdev = true;
 }
 
 static struct net_device *qmimux_find_dev(struct usbnet *dev, u8 mux_id)
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 38f0f03..0156fe8 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -222,7 +222,6 @@  static int veth_dev_init(struct net_device *dev)
 static void veth_dev_free(struct net_device *dev)
 {
 	free_percpu(dev->vstats);
-	free_netdev(dev);
 }
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
@@ -317,7 +316,8 @@  static void veth_setup(struct net_device *dev)
 			       NETIF_F_HW_VLAN_STAG_TX |
 			       NETIF_F_HW_VLAN_CTAG_RX |
 			       NETIF_F_HW_VLAN_STAG_RX);
-	dev->destructor = veth_dev_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = veth_dev_free;
 	dev->max_mtu = ETH_MAX_MTU;
 
 	dev->hw_features = VETH_FEATURES;
diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index ceda586..de3dcbb 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -1347,7 +1347,7 @@  static void vrf_setup(struct net_device *dev)
 	dev->netdev_ops = &vrf_netdev_ops;
 	dev->l3mdev_ops = &vrf_l3mdev_ops;
 	dev->ethtool_ops = &vrf_ethtool_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 
 	/* Fill in device structure with ethernet-generic values. */
 	eth_hw_addr_random(dev);
diff --git a/drivers/net/vsockmon.c b/drivers/net/vsockmon.c
index 7f0136f..c28bdce 100644
--- a/drivers/net/vsockmon.c
+++ b/drivers/net/vsockmon.c
@@ -135,7 +135,7 @@  static void vsockmon_setup(struct net_device *dev)
 
 	dev->netdev_ops	= &vsockmon_ops;
 	dev->ethtool_ops = &vsockmon_ethtool_ops;
-	dev->destructor	= free_netdev;
+	dev->needs_free_netdev = true;
 
 	dev->features = NETIF_F_SG | NETIF_F_FRAGLIST |
 			NETIF_F_HIGHDMA | NETIF_F_LLTX;
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 328b471..927c6a9 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -2584,7 +2584,7 @@  static void vxlan_setup(struct net_device *dev)
 	eth_hw_addr_random(dev);
 	ether_setup(dev);
 
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	SET_NETDEV_DEVTYPE(dev, &vxlan_type);
 
 	dev->features	|= NETIF_F_LLTX;
diff --git a/drivers/net/wan/dlci.c b/drivers/net/wan/dlci.c
index 65ee2a6..a0d76f7 100644
--- a/drivers/net/wan/dlci.c
+++ b/drivers/net/wan/dlci.c
@@ -475,7 +475,7 @@  static void dlci_setup(struct net_device *dev)
 	dev->flags		= 0;
 	dev->header_ops		= &dlci_header_ops;
 	dev->netdev_ops		= &dlci_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 
 	dlp->receive		= dlci_receive;
 
diff --git a/drivers/net/wan/hdlc_fr.c b/drivers/net/wan/hdlc_fr.c
index eb91528..78596e4 100644
--- a/drivers/net/wan/hdlc_fr.c
+++ b/drivers/net/wan/hdlc_fr.c
@@ -1106,7 +1106,7 @@  static int fr_add_pvc(struct net_device *frad, unsigned int dlci, int type)
 		return -EIO;
 	}
 
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	*get_dev_p(pvc, type) = dev;
 	if (!used) {
 		state(hdlc)->dce_changed = 1;
diff --git a/drivers/net/wan/lapbether.c b/drivers/net/wan/lapbether.c
index 9df9ed6..63f7490 100644
--- a/drivers/net/wan/lapbether.c
+++ b/drivers/net/wan/lapbether.c
@@ -306,7 +306,7 @@  static const struct net_device_ops lapbeth_netdev_ops = {
 static void lapbeth_setup(struct net_device *dev)
 {
 	dev->netdev_ops	     = &lapbeth_netdev_ops;
-	dev->destructor	     = free_netdev;
+	dev->needs_free_netdev = true;
 	dev->type            = ARPHRD_X25;
 	dev->hard_header_len = 3;
 	dev->mtu             = 1000;
diff --git a/drivers/net/wireless/ath/ath6kl/main.c b/drivers/net/wireless/ath/ath6kl/main.c
index 91ee542..b90c77e 100644
--- a/drivers/net/wireless/ath/ath6kl/main.c
+++ b/drivers/net/wireless/ath/ath6kl/main.c
@@ -1287,7 +1287,7 @@  void init_netdev(struct net_device *dev)
 	struct ath6kl *ar = ath6kl_priv(dev);
 
 	dev->netdev_ops = &ath6kl_netdev_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	dev->watchdog_timeo = ATH6KL_TX_TIMEOUT;
 
 	dev->needed_headroom = ETH_HLEN;
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
index cd1d673..617199c 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
@@ -5225,7 +5225,6 @@  void brcmf_cfg80211_free_netdev(struct net_device *ndev)
 
 	if (vif)
 		brcmf_free_vif(vif);
-	free_netdev(ndev);
 }
 
 static bool brcmf_is_linkup(const struct brcmf_event_msg *e)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index a3d8236..511d190 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -624,7 +624,8 @@  struct brcmf_if *brcmf_add_if(struct brcmf_pub *drvr, s32 bsscfgidx, s32 ifidx,
 		if (!ndev)
 			return ERR_PTR(-ENOMEM);
 
-		ndev->destructor = brcmf_cfg80211_free_netdev;
+		ndev->needs_free_netdev = true;
+		ndev->priv_destructor = brcmf_cfg80211_free_netdev;
 		ifp = netdev_priv(ndev);
 		ifp->ndev = ndev;
 		/* store mapping ifidx to bsscfgidx */
diff --git a/drivers/net/wireless/intersil/hostap/hostap_main.c b/drivers/net/wireless/intersil/hostap/hostap_main.c
index 544fc09..1372b20 100644
--- a/drivers/net/wireless/intersil/hostap/hostap_main.c
+++ b/drivers/net/wireless/intersil/hostap/hostap_main.c
@@ -73,7 +73,7 @@  struct net_device * hostap_add_interface(struct local_info *local,
 	dev->mem_end = mdev->mem_end;
 
 	hostap_setup_dev(dev, local, type);
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 
 	sprintf(dev->name, "%s%s", prefix, name);
 	if (!rtnl_locked)
diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index 87444af..a659104 100644
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -2855,7 +2855,7 @@  static const struct net_device_ops hwsim_netdev_ops = {
 static void hwsim_mon_setup(struct net_device *dev)
 {
 	dev->netdev_ops = &hwsim_netdev_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	ether_setup(dev);
 	dev->priv_flags |= IFF_NO_QUEUE;
 	dev->type = ARPHRD_IEEE80211_RADIOTAP;
diff --git a/drivers/net/wireless/marvell/mwifiex/main.c b/drivers/net/wireless/marvell/mwifiex/main.c
index dd87b9f..39b6b5e 100644
--- a/drivers/net/wireless/marvell/mwifiex/main.c
+++ b/drivers/net/wireless/marvell/mwifiex/main.c
@@ -1280,7 +1280,7 @@  void mwifiex_init_priv_params(struct mwifiex_private *priv,
 			      struct net_device *dev)
 {
 	dev->netdev_ops = &mwifiex_netdev_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	/* Initialize private structure */
 	priv->current_key_index = 0;
 	priv->media_connected = false;
diff --git a/drivers/staging/rtl8188eu/os_dep/mon.c b/drivers/staging/rtl8188eu/os_dep/mon.c
index cfe37eb..859d0d6 100644
--- a/drivers/staging/rtl8188eu/os_dep/mon.c
+++ b/drivers/staging/rtl8188eu/os_dep/mon.c
@@ -152,7 +152,7 @@  static const struct net_device_ops mon_netdev_ops = {
 static void mon_setup(struct net_device *dev)
 {
 	dev->netdev_ops = &mon_netdev_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	ether_setup(dev);
 	dev->priv_flags |= IFF_NO_QUEUE;
 	dev->type = ARPHRD_IEEE80211;
diff --git a/drivers/usb/gadget/function/f_phonet.c b/drivers/usb/gadget/function/f_phonet.c
index b4058f0..6a1ce6a 100644
--- a/drivers/usb/gadget/function/f_phonet.c
+++ b/drivers/usb/gadget/function/f_phonet.c
@@ -281,7 +281,7 @@  static void pn_net_setup(struct net_device *dev)
 	dev->tx_queue_len	= 1;
 
 	dev->netdev_ops		= &pn_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 	dev->header_ops		= &phonet_header_ops;
 }
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 9c23bd2..2ead32a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1596,8 +1596,8 @@  enum netdev_priv_flags {
  *	@rtnl_link_state:	This enum represents the phases of creating
  *				a new link
  *
- *	@destructor:		Called from unregister,
- *				can be used to call free_netdev
+ *	@needs_free_netdev:	Should unregister perform free_netdev?
+ *	@priv_destructor:	Called from unregister
  *	@npinfo:		XXX: need comments on this one
  * 	@nd_net:		Network namespace this network device is inside
  *
@@ -1858,7 +1858,8 @@  struct net_device {
 		RTNL_LINK_INITIALIZING,
 	} rtnl_link_state:16;
 
-	void (*destructor)(struct net_device *dev);
+	bool needs_free_netdev;
+	void (*priv_destructor)(struct net_device *dev);
 
 #ifdef CONFIG_NETPOLL
 	struct netpoll_info __rcu	*npinfo;
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index 9ee5787..33885dc 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -806,7 +806,6 @@  static void vlan_dev_free(struct net_device *dev)
 
 	free_percpu(vlan->vlan_pcpu_stats);
 	vlan->vlan_pcpu_stats = NULL;
-	free_netdev(dev);
 }
 
 void vlan_setup(struct net_device *dev)
@@ -819,7 +818,8 @@  void vlan_setup(struct net_device *dev)
 	netif_keep_dst(dev);
 
 	dev->netdev_ops		= &vlan_netdev_ops;
-	dev->destructor		= vlan_dev_free;
+	dev->needs_free_netdev	= true;
+	dev->priv_destructor	= vlan_dev_free;
 	dev->ethtool_ops	= &vlan_ethtool_ops;
 
 	dev->min_mtu		= 0;
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index b25789a..10f7edf 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -1034,8 +1034,6 @@  static void batadv_softif_free(struct net_device *dev)
 	 * netdev and its private data (bat_priv)
 	 */
 	rcu_barrier();
-
-	free_netdev(dev);
 }
 
 /**
@@ -1047,7 +1045,8 @@  static void batadv_softif_init_early(struct net_device *dev)
 	ether_setup(dev);
 
 	dev->netdev_ops = &batadv_netdev_ops;
-	dev->destructor = batadv_softif_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = batadv_softif_free;
 	dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_NETNS_LOCAL;
 	dev->priv_flags |= IFF_NO_QUEUE;
 
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 6089599..ab3b654 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -598,7 +598,7 @@  static void netdev_setup(struct net_device *dev)
 
 	dev->netdev_ops		= &netdev_ops;
 	dev->header_ops		= &header_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 }
 
 static struct device_type bt_type = {
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 430b53e..f0f3447 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -379,7 +379,7 @@  void br_dev_setup(struct net_device *dev)
 	ether_setup(dev);
 
 	dev->netdev_ops = &br_netdev_ops;
-	dev->destructor = free_netdev;
+	dev->needs_free_netdev = true;
 	dev->ethtool_ops = &br_ethtool_ops;
 	SET_NETDEV_DEVTYPE(dev, &br_type);
 	dev->priv_flags = IFF_EBRIDGE | IFF_NO_QUEUE;
diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c
index 1816fc9..fe3c53e 100644
--- a/net/caif/chnl_net.c
+++ b/net/caif/chnl_net.c
@@ -392,14 +392,14 @@  static void chnl_net_destructor(struct net_device *dev)
 {
 	struct chnl_net *priv = netdev_priv(dev);
 	caif_free_client(&priv->chnl);
-	free_netdev(dev);
 }
 
 static void ipcaif_net_setup(struct net_device *dev)
 {
 	struct chnl_net *priv;
 	dev->netdev_ops = &netdev_ops;
-	dev->destructor = chnl_net_destructor;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = chnl_net_destructor;
 	dev->flags |= IFF_NOARP;
 	dev->flags |= IFF_POINTOPOINT;
 	dev->mtu = GPRS_PDP_MTU;
diff --git a/net/core/dev.c b/net/core/dev.c
index d07aa5f..7507fea 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -7485,6 +7485,8 @@  int register_netdevice(struct net_device *dev)
 err_uninit:
 	if (dev->netdev_ops->ndo_uninit)
 		dev->netdev_ops->ndo_uninit(dev);
+	if (dev->priv_destructor)
+		dev->priv_destructor(dev);
 	goto out;
 }
 EXPORT_SYMBOL(register_netdevice);
@@ -7692,8 +7694,10 @@  void netdev_run_todo(void)
 		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
 		WARN_ON(dev->dn_ptr);
 
-		if (dev->destructor)
-			dev->destructor(dev);
+		if (dev->priv_destructor)
+			dev->priv_destructor(dev);
+		if (dev->needs_free_netdev)
+			free_netdev(dev);
 
 		/* Report a network device has been unregistered */
 		rtnl_lock();
diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
index c73160f..0a0a392 100644
--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c
@@ -378,7 +378,6 @@  static void hsr_dev_destroy(struct net_device *hsr_dev)
 	del_timer_sync(&hsr->announce_timer);
 
 	synchronize_rcu();
-	free_netdev(hsr_dev);
 }
 
 static const struct net_device_ops hsr_device_ops = {
@@ -404,7 +403,8 @@  void hsr_dev_setup(struct net_device *dev)
 	SET_NETDEV_DEVTYPE(dev, &hsr_type);
 	dev->priv_flags |= IFF_NO_QUEUE;
 
-	dev->destructor = hsr_dev_destroy;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = hsr_dev_destroy;
 
 	dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
 			   NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c
index d7efbf0..0a866f33 100644
--- a/net/ieee802154/6lowpan/core.c
+++ b/net/ieee802154/6lowpan/core.c
@@ -107,7 +107,7 @@  static void lowpan_setup(struct net_device *ldev)
 
 	ldev->netdev_ops	= &lowpan_netdev_ops;
 	ldev->header_ops	= &lowpan_header_ops;
-	ldev->destructor	= free_netdev;
+	ldev->needs_free_netdev	= true;
 	ldev->features		|= NETIF_F_NETNS_LOCAL;
 }
 
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index b878ecb..b436d07 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -967,7 +967,6 @@  static void ip_tunnel_dev_free(struct net_device *dev)
 	gro_cells_destroy(&tunnel->gro_cells);
 	dst_cache_destroy(&tunnel->dst_cache);
 	free_percpu(dev->tstats);
-	free_netdev(dev);
 }
 
 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
@@ -1155,7 +1154,8 @@  int ip_tunnel_init(struct net_device *dev)
 	struct iphdr *iph = &tunnel->parms.iph;
 	int err;
 
-	dev->destructor	= ip_tunnel_dev_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = ip_tunnel_dev_free;
 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 	if (!dev->tstats)
 		return -ENOMEM;
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 3a02d52..200b65a 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -501,7 +501,7 @@  static void reg_vif_setup(struct net_device *dev)
 	dev->mtu		= ETH_DATA_LEN - sizeof(struct iphdr) - 8;
 	dev->flags		= IFF_NOARP;
 	dev->netdev_ops		= &reg_vif_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 	dev->features		|= NETIF_F_NETNS_LOCAL;
 }
 
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 8d128ba..c8c386a 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -990,13 +990,13 @@  static void ip6gre_dev_free(struct net_device *dev)
 
 	dst_cache_destroy(&t->dst_cache);
 	free_percpu(dev->tstats);
-	free_netdev(dev);
 }
 
 static void ip6gre_tunnel_setup(struct net_device *dev)
 {
 	dev->netdev_ops = &ip6gre_netdev_ops;
-	dev->destructor = ip6gre_dev_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = ip6gre_dev_free;
 
 	dev->type = ARPHRD_IP6GRE;
 
@@ -1147,7 +1147,7 @@  static int __net_init ip6gre_init_net(struct net *net)
 	return 0;
 
 err_reg_dev:
-	ip6gre_dev_free(ign->fb_tunnel_dev);
+	free_netdev(ign->fb_tunnel_dev);
 err_alloc_dev:
 	return err;
 }
@@ -1299,7 +1299,8 @@  static void ip6gre_tap_setup(struct net_device *dev)
 	ether_setup(dev);
 
 	dev->netdev_ops = &ip6gre_tap_netdev_ops;
-	dev->destructor = ip6gre_dev_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = ip6gre_dev_free;
 
 	dev->features |= NETIF_F_NETNS_LOCAL;
 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 6eb2ae5..883b652 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -254,7 +254,6 @@  static void ip6_dev_free(struct net_device *dev)
 	gro_cells_destroy(&t->gro_cells);
 	dst_cache_destroy(&t->dst_cache);
 	free_percpu(dev->tstats);
-	free_netdev(dev);
 }
 
 static int ip6_tnl_create2(struct net_device *dev)
@@ -322,7 +321,7 @@  static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
 	return t;
 
 failed_free:
-	ip6_dev_free(dev);
+	free_netdev(dev);
 failed:
 	return ERR_PTR(err);
 }
@@ -1769,7 +1768,8 @@  static const struct net_device_ops ip6_tnl_netdev_ops = {
 static void ip6_tnl_dev_setup(struct net_device *dev)
 {
 	dev->netdev_ops = &ip6_tnl_netdev_ops;
-	dev->destructor = ip6_dev_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = ip6_dev_free;
 
 	dev->type = ARPHRD_TUNNEL6;
 	dev->flags |= IFF_NOARP;
@@ -2216,7 +2216,7 @@  static int __net_init ip6_tnl_init_net(struct net *net)
 	return 0;
 
 err_register:
-	ip6_dev_free(ip6n->fb_tnl_dev);
+	free_netdev(ip6n->fb_tnl_dev);
 err_alloc_dev:
 	return err;
 }
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index d67ef56..837ea1e 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -180,7 +180,6 @@  vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
 static void vti6_dev_free(struct net_device *dev)
 {
 	free_percpu(dev->tstats);
-	free_netdev(dev);
 }
 
 static int vti6_tnl_create2(struct net_device *dev)
@@ -235,7 +234,7 @@  static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p
 	return t;
 
 failed_free:
-	vti6_dev_free(dev);
+	free_netdev(dev);
 failed:
 	return NULL;
 }
@@ -842,7 +841,8 @@  static const struct net_device_ops vti6_netdev_ops = {
 static void vti6_dev_setup(struct net_device *dev)
 {
 	dev->netdev_ops = &vti6_netdev_ops;
-	dev->destructor = vti6_dev_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = vti6_dev_free;
 
 	dev->type = ARPHRD_TUNNEL6;
 	dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
@@ -1100,7 +1100,7 @@  static int __net_init vti6_init_net(struct net *net)
 	return 0;
 
 err_register:
-	vti6_dev_free(ip6n->fb_tnl_dev);
+	free_netdev(ip6n->fb_tnl_dev);
 err_alloc_dev:
 	return err;
 }
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 374997d..2ecb39b 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -733,7 +733,7 @@  static void reg_vif_setup(struct net_device *dev)
 	dev->mtu		= 1500 - sizeof(struct ipv6hdr) - 8;
 	dev->flags		= IFF_NOARP;
 	dev->netdev_ops		= &reg_vif_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 	dev->features		|= NETIF_F_NETNS_LOCAL;
 }
 
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 61e5902..2378503 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -265,7 +265,7 @@  static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
 	return nt;
 
 failed_free:
-	ipip6_dev_free(dev);
+	free_netdev(dev);
 failed:
 	return NULL;
 }
@@ -1336,7 +1336,6 @@  static void ipip6_dev_free(struct net_device *dev)
 
 	dst_cache_destroy(&tunnel->dst_cache);
 	free_percpu(dev->tstats);
-	free_netdev(dev);
 }
 
 #define SIT_FEATURES (NETIF_F_SG	   | \
@@ -1351,7 +1350,8 @@  static void ipip6_tunnel_setup(struct net_device *dev)
 	int t_hlen = tunnel->hlen + sizeof(struct iphdr);
 
 	dev->netdev_ops		= &ipip6_netdev_ops;
-	dev->destructor		= ipip6_dev_free;
+	dev->needs_free_netdev	= true;
+	dev->priv_destructor	= ipip6_dev_free;
 
 	dev->type		= ARPHRD_SIT;
 	dev->hard_header_len	= LL_MAX_HEADER + t_hlen;
diff --git a/net/irda/irlan/irlan_eth.c b/net/irda/irlan/irlan_eth.c
index 74d09f9..3be8528 100644
--- a/net/irda/irlan/irlan_eth.c
+++ b/net/irda/irlan/irlan_eth.c
@@ -65,7 +65,7 @@  static void irlan_eth_setup(struct net_device *dev)
 	ether_setup(dev);
 
 	dev->netdev_ops		= &irlan_eth_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 	dev->min_mtu		= 0;
 	dev->max_mtu		= ETH_MAX_MTU;
 
diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c
index 8b21af7..f7c54ec 100644
--- a/net/l2tp/l2tp_eth.c
+++ b/net/l2tp/l2tp_eth.c
@@ -141,7 +141,7 @@  static void l2tp_eth_dev_setup(struct net_device *dev)
 	dev->priv_flags		&= ~IFF_TX_SKB_SHARING;
 	dev->features		|= NETIF_F_LLTX;
 	dev->netdev_ops		= &l2tp_eth_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 }
 
 static void l2tp_eth_dev_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 3bd5b81..267e965 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1213,7 +1213,6 @@  static const struct net_device_ops ieee80211_monitorif_ops = {
 static void ieee80211_if_free(struct net_device *dev)
 {
 	free_percpu(dev->tstats);
-	free_netdev(dev);
 }
 
 static void ieee80211_if_setup(struct net_device *dev)
@@ -1221,7 +1220,8 @@  static void ieee80211_if_setup(struct net_device *dev)
 	ether_setup(dev);
 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 	dev->netdev_ops = &ieee80211_dataif_ops;
-	dev->destructor = ieee80211_if_free;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = ieee80211_if_free;
 }
 
 static void ieee80211_if_setup_no_queue(struct net_device *dev)
@@ -1914,7 +1914,7 @@  int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 
 		ret = register_netdevice(ndev);
 		if (ret) {
-			ieee80211_if_free(ndev);
+			free_netdev(ndev);
 			return ret;
 		}
 	}
diff --git a/net/mac802154/iface.c b/net/mac802154/iface.c
index 06019db..bd88a9b 100644
--- a/net/mac802154/iface.c
+++ b/net/mac802154/iface.c
@@ -526,8 +526,6 @@  static void mac802154_wpan_free(struct net_device *dev)
 	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
 
 	mac802154_llsec_destroy(&sdata->sec);
-
-	free_netdev(dev);
 }
 
 static void ieee802154_if_setup(struct net_device *dev)
@@ -593,7 +591,8 @@  ieee802154_setup_sdata(struct ieee802154_sub_if_data *sdata,
 					sdata->dev->dev_addr);
 
 		sdata->dev->header_ops = &mac802154_header_ops;
-		sdata->dev->destructor = mac802154_wpan_free;
+		sdata->dev->needs_free_netdev = true;
+		sdata->dev->priv_destructor = mac802154_wpan_free;
 		sdata->dev->netdev_ops = &mac802154_wpan_ops;
 		sdata->dev->ml_priv = &mac802154_mlme_wpan;
 		wpan_dev->promiscuous_mode = false;
@@ -608,7 +607,7 @@  ieee802154_setup_sdata(struct ieee802154_sub_if_data *sdata,
 
 		break;
 	case NL802154_IFTYPE_MONITOR:
-		sdata->dev->destructor = free_netdev;
+		sdata->dev->needs_free_netdev = true;
 		sdata->dev->netdev_ops = &mac802154_monitor_ops;
 		wpan_dev->promiscuous_mode = true;
 		break;
diff --git a/net/openvswitch/vport-internal_dev.c b/net/openvswitch/vport-internal_dev.c
index 89193a6..04a3128 100644
--- a/net/openvswitch/vport-internal_dev.c
+++ b/net/openvswitch/vport-internal_dev.c
@@ -94,7 +94,6 @@  static void internal_dev_destructor(struct net_device *dev)
 	struct vport *vport = ovs_internal_dev_get_vport(dev);
 
 	ovs_vport_free(vport);
-	free_netdev(dev);
 }
 
 static void
@@ -156,7 +155,8 @@  static void do_setup(struct net_device *netdev)
 	netdev->priv_flags &= ~IFF_TX_SKB_SHARING;
 	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH |
 			      IFF_PHONY_HEADROOM | IFF_NO_QUEUE;
-	netdev->destructor = internal_dev_destructor;
+	netdev->needs_free_netdev = true;
+	netdev->priv_destructor = internal_dev_destructor;
 	netdev->ethtool_ops = &internal_dev_ethtool_ops;
 	netdev->rtnl_link_ops = &internal_dev_link_ops;
 
diff --git a/net/phonet/pep-gprs.c b/net/phonet/pep-gprs.c
index 21c28b5..2c93379 100644
--- a/net/phonet/pep-gprs.c
+++ b/net/phonet/pep-gprs.c
@@ -236,7 +236,7 @@  static void gprs_setup(struct net_device *dev)
 	dev->tx_queue_len	= 10;
 
 	dev->netdev_ops		= &gprs_netdev_ops;
-	dev->destructor		= free_netdev;
+	dev->needs_free_netdev	= true;
 }
 
 /*