Re: [patch] lockdep annotate vlan net device as being a special class

[Frederik Deweerdt <deweerdt@free.fr>]

On Tue, Jun 27, 2006 at 10:09:08AM -0400, Peter Staubach wrote:
> Shouldn't this test for new_dev being NULL _before_ it gets used?
Indeed, it should. But the lock is inited in register_netdevice anyway.
I tested (compile+boot+ifconfig) the following patch to mm3, and the trace went
away.

Regards,
Frederik

Signed-Off-By: Frederik Deweerdt <frederik.deweerdt@gmail.com>

--- v2.6.17-mm3/net/8021q/vlan.c        2006-06-27 19:02:14.000000000 +0200
+++ v2.6.17-mm3~mod/net/8021q/vlan.c    2006-06-27 18:50:48.000000000 +0200
@@ -469,7 +469,6 @@ static struct net_device *register_vlan_
        new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name,
                               vlan_setup);

-       lockdep_set_class(&new_dev->_xmit_lock, &vlan_netdev_xmit_lock_key);
        if (new_dev == NULL)
                goto out_unlock;

@@ -528,6 +527,8 @@ static struct net_device *register_vlan_
        if (register_netdevice(new_dev))
                goto out_free_newdev;

+       lockdep_set_class(&new_dev->_xmit_lock, &vlan_netdev_xmit_lock_key);
+
        new_dev->iflink = real_dev->ifindex;
        vlan_transfer_operstate(real_dev, new_dev);
        linkwatch_fire_event(new_dev); /* _MUST_ call rfc2863_policy() */