From 952fcfd08c8109951622579d0ae7b9cd6cafd688 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Fri, 12 Aug 2016 16:10:33 +0200 Subject: net: remove type_check from dev_get_nest_level() The idea for type_check in dev_get_nest_level() was to count the number of nested devices of the same type (currently, only macvlan or vlan devices). This prevented the false positive lockdep warning on configurations such as: eth0 <--- macvlan0 <--- vlan0 <--- macvlan1 However, this doesn't prevent a warning on a configuration such as: eth0 <--- macvlan0 <--- vlan0 eth1 <--- vlan1 <--- macvlan1 In this case, all the locks end up with a nesting subclass of 1, so lockdep thinks that there is still a deadlock: - in the first case we have (macvlan_netdev_addr_lock_key, 1) and then take (vlan_netdev_xmit_lock_key, 1) - in the second case, we have (vlan_netdev_xmit_lock_key, 1) and then take (macvlan_netdev_addr_lock_key, 1) By removing the linktype check in dev_get_nest_level() and always incrementing the nesting depth, lockdep considers this configuration valid. Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller --- drivers/net/macsec.c | 2 +- drivers/net/macvlan.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 2043e8c97a81..351e701eb043 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -3201,7 +3201,7 @@ static int macsec_newlink(struct net *net, struct net_device *dev, dev_hold(real_dev); - macsec->nest_level = dev_get_nest_level(real_dev, netif_is_macsec) + 1; + macsec->nest_level = dev_get_nest_level(real_dev) + 1; netdev_lockdep_set_classes(dev); lockdep_set_class_and_subclass(&dev->addr_list_lock, &macsec_netdev_addr_lock_key, diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index cd9b53834bf6..3234fcdea317 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -1315,7 +1315,7 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev, vlan->dev = dev; vlan->port = port; vlan->set_features = MACVLAN_FEATURES; - vlan->nest_level = dev_get_nest_level(lowerdev, netif_is_macvlan) + 1; + vlan->nest_level = dev_get_nest_level(lowerdev) + 1; vlan->mode = MACVLAN_MODE_VEPA; if (data && data[IFLA_MACVLAN_MODE]) -- cgit v1.2.3