Merge branch 'stacked_netdevice_locking'

Vlad Yasevich says:

====================
Fix lockdep issues with stacked devices

Recent commit dc8eaaa006350d24030502a4521542e74b5cb39f
    vlan: Fix lockdep warning when vlan dev handle notification

attempted to solve lockdep issues with vlans where multiple
vlans were stacked.  However, the code does not work correctly
when the vlan stack is interspersed with other devices in between
the vlans.  Additionally, similar lockdep issues show up with other
devices.

This series provides a generic way to solve these issue for any
devices that can be stacked.  It also addresses the concern for
vlan and macvlan devices.  I am not sure whether it makes sense
to do so for other types like team, vxlan, and bond.

Thanks
-vlad

Since v2:
  - Remove rcu variants from patch1, since that function is called
    only under rtnl.
  - Fix whitespace problems reported by checkpatch

Since v1:
  - Fixed up a goofed-up rebase.
    * is_vlan_dev() should be bool and that change belongs in patch3.
    * patch4 should not have any vlan changes in it.
====================

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

3 files changed, 20 insertions, 2 deletions

diff --git a/include/linux/if_macvlan.h b/include/linux/if_macvlan.h
index 7c8b20b120ea..a9a53b12397b 100644
--- a/include/linux/if_macvlan.h
+++ b/include/linux/if_macvlan.h
@@ -56,6 +56,7 @@ struct macvlan_dev {
         int                     numqueues;
         netdev_features_t       tap_features;
         int                     minor;
+        int                     nest_level;
 };
 
 static inline void macvlan_count_rx(const struct macvlan_dev *vlan,
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 13bbbde00e68..724bde8477b2 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -73,7 +73,7 @@ static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
 /* found in socket.c */
 extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
 
-static inline int is_vlan_dev(struct net_device *dev)
+static inline bool is_vlan_dev(struct net_device *dev)
 {
         return dev->priv_flags & IFF_802_1Q_VLAN;
 }
@@ -159,6 +159,7 @@ struct vlan_dev_priv {
 #ifdef CONFIG_NET_POLL_CONTROLLER
         struct netpoll                          *netpoll;
 #endif
+        unsigned int                            nest_level;
 };
 
 static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 20e99efb1ca6..9d4b1f1b6b75 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1144,6 +1144,7 @@ struct net_device_ops {
         netdev_tx_t             (*ndo_dfwd_start_xmit) (struct sk_buff *skb,
                                                         struct net_device *dev,
                                                         void *priv);
+        int                     (*ndo_get_lock_subclass)(struct net_device *dev);
 };
 
 /**
@@ -2950,7 +2951,12 @@ static inline void netif_addr_lock(struct net_device *dev)
 
 static inline void netif_addr_lock_nested(struct net_device *dev)
 {
-        spin_lock_nested(&dev->addr_list_lock, SINGLE_DEPTH_NESTING);
+        int subclass = SINGLE_DEPTH_NESTING;
+
+        if (dev->netdev_ops->ndo_get_lock_subclass)
+                subclass = dev->netdev_ops->ndo_get_lock_subclass(dev);
+
+        spin_lock_nested(&dev->addr_list_lock, subclass);
 }
 
 static inline void netif_addr_lock_bh(struct net_device *dev)
@@ -3077,6 +3083,14 @@ void *netdev_lower_get_next_private_rcu(struct net_device *dev,
              priv; \
              priv = netdev_lower_get_next_private_rcu(dev, &(iter)))
 
+void *netdev_lower_get_next(struct net_device *dev,
+                                struct list_head **iter);
+#define netdev_for_each_lower_dev(dev, ldev, iter) \
+        for (iter = &(dev)->adj_list.lower, \
+             ldev = netdev_lower_get_next(dev, &(iter)); \
+             ldev; \
+             ldev = netdev_lower_get_next(dev, &(iter)))
+
 void *netdev_adjacent_get_private(struct list_head *adj_list);
 void *netdev_lower_get_first_private_rcu(struct net_device *dev);
 struct net_device *netdev_master_upper_dev_get(struct net_device *dev);
@@ -3092,6 +3106,8 @@ void netdev_upper_dev_unlink(struct net_device *dev,
 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname);
 void *netdev_lower_dev_get_private(struct net_device *dev,
                                    struct net_device *lower_dev);
+int dev_get_nest_level(struct net_device *dev,
+                       bool (*type_check)(struct net_device *dev));
 int skb_checksum_help(struct sk_buff *skb);
 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
                                   netdev_features_t features, bool tx_path);