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 <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index cd9b538..3234fcd 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1315,7 +1315,7 @@
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])