From aaf8cdc34ddba08122f02217d9d684e2f9f5d575 Mon Sep 17 00:00:00 2001 From: Daniel Lezcano Date: Fri, 2 May 2008 17:00:58 -0700 Subject: [PATCH] netns: Fix device renaming for sysfs When a netdev is moved across namespaces with the 'dev_change_net_namespace' function, the 'device_rename' function is used to fixup kobject and refresh the sysfs tree. The device_rename function will call kobject_rename and this one will check if there is an object with the same name and this is the case because we are renaming the object with the same name. The use of 'device_rename' seems for me wrong because we usually don't rename it but just move it across namespaces. As we just want to do a mini "netdev_[un]register", IMO the functions 'netdev_[un]register_kobject' should be used instead, like an usual network device [un]registering. This patch replace device_rename by netdev_unregister_kobject, followed by netdev_register_kobject. The netdev_register_kobject will call device_initialize and will raise a warning indicating the device was already initialized. In order to fix that, I split the device initialization into a separate function and use it together with 'netdev_register_kobject' into register_netdevice. So we can safely call 'netdev_register_kobject' in 'dev_change_net_namespace'. This fix will allow to properly use the sysfs per namespace which is coming from -mm tree. Signed-off-by: Daniel Lezcano Acked-by: Benjamin Thery Signed-off-by: David S. Miller --- net/core/dev.c | 4 +++- net/core/net-sysfs.c | 7 ++++++- net/core/net-sysfs.h | 2 +- 3 files changed, 10 insertions(+), 3 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index a9500e6b3aa..d334446a8ea 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3776,6 +3776,7 @@ int register_netdevice(struct net_device *dev) } } + netdev_initialize_kobject(dev); ret = netdev_register_kobject(dev); if (ret) goto err_uninit; @@ -4208,7 +4209,8 @@ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char } /* Fixup kobjects */ - err = device_rename(&dev->dev, dev->name); + netdev_unregister_kobject(dev); + err = netdev_register_kobject(dev); WARN_ON(err); /* Add the device back in the hashes */ diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 4e7b847347f..90e2177af08 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -449,7 +449,6 @@ int netdev_register_kobject(struct net_device *net) struct device *dev = &(net->dev); struct attribute_group **groups = net->sysfs_groups; - device_initialize(dev); dev->class = &net_class; dev->platform_data = net; dev->groups = groups; @@ -470,6 +469,12 @@ int netdev_register_kobject(struct net_device *net) return device_add(dev); } +void netdev_initialize_kobject(struct net_device *net) +{ + struct device *device = &(net->dev); + device_initialize(device); +} + int netdev_kobject_init(void) { return class_register(&net_class); diff --git a/net/core/net-sysfs.h b/net/core/net-sysfs.h index f5f108db392..14e7524260b 100644 --- a/net/core/net-sysfs.h +++ b/net/core/net-sysfs.h @@ -4,5 +4,5 @@ int netdev_kobject_init(void); int netdev_register_kobject(struct net_device *); void netdev_unregister_kobject(struct net_device *); - +void netdev_initialize_kobject(struct net_device *); #endif