[PATCH RFC net-next 4/6] net: Do not intialize kobject for lightweight netdevs

[David Ahern]

Lightweight netdevices are not added to sysfs; bypass kobject
initialization.

Signed-off-by: David Ahern <dsah...@gmail.com>
---
 include/linux/netdevice.h |  3 +++
 net/core/dev.c            |  9 ++++++---
 net/core/net-sysfs.c      | 14 +++++++++++---
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 08151fd34973..4ddd0ac7e1cb 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4282,6 +4282,9 @@ static inline const char *netdev_reg_state(const struct 
net_device *dev)
 
 static inline struct kobject *netdev_kobject(struct net_device *dev)
 {
+       if (netif_is_lwd(dev))
+               return NULL;
+
        return &dev->dev.kobj;
 }
 
diff --git a/net/core/dev.c b/net/core/dev.c
index 48a0252037d5..52bb01041d12 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -7993,7 +7993,8 @@ void free_netdev(struct net_device *dev)
        dev->reg_state = NETREG_RELEASED;
 
        /* will free via device release */
-       put_device(&dev->dev);
+       if (!netif_is_lwd(dev))
+               put_device(&dev->dev);
 }
 EXPORT_SYMBOL(free_netdev);
 
@@ -8179,8 +8180,10 @@ int dev_change_net_namespace(struct net_device *dev, 
struct net *net, const char
        netdev_adjacent_add_links(dev);
 
        /* Fixup kobjects */
-       err = device_rename(&dev->dev, dev->name);
-       WARN_ON(err);
+       if (!netif_is_lwd(dev)) {
+               err = device_rename(&dev->dev, dev->name);
+               WARN_ON(err);
+       }
 
        /* Add the device back in the hashes */
        list_netdevice(dev);
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 9df53b688f5b..725348cdeb3b 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -1559,18 +1559,22 @@ EXPORT_SYMBOL(of_find_net_device_by_node);
  */
 void netdev_unregister_kobject(struct net_device *ndev)
 {
+       struct kobject *kobj = netdev_kobject(ndev);
        struct device *dev = &(ndev->dev);
 
        if (!atomic_read(&dev_net(ndev)->count))
                dev_set_uevent_suppress(dev, 1);
 
-       kobject_get(&dev->kobj);
+       if (kobj)
+               kobject_get(kobj);
 
-       remove_queue_kobjects(ndev);
+       if (!netif_is_lwd(ndev))
+               remove_queue_kobjects(ndev);
 
        pm_runtime_set_memalloc_noio(dev, false);
 
-       device_del(dev);
+       if (!netif_is_lwd(ndev))
+               device_del(dev);
 }
 
 /* Create sysfs entries for network device. */
@@ -1580,6 +1584,9 @@ int netdev_register_kobject(struct net_device *ndev)
        const struct attribute_group **groups = ndev->sysfs_groups;
        int error = 0;
 
+       if (netif_is_lwd(ndev))
+               goto pm;
+
        device_initialize(dev);
        dev->class = &net_class;
        dev->platform_data = ndev;
@@ -1614,6 +1621,7 @@ int netdev_register_kobject(struct net_device *ndev)
                return error;
        }
 
+pm:
        pm_runtime_set_memalloc_noio(dev, true);
 
        return error;
-- 
2.11.0 (Apple Git-81)