From 728c02089a0e3eefb02e9927bfae50490f40e72e Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 16 Jan 2015 09:56:01 -0800 Subject: [PATCH] net: ipv4: handle DSA enabled master network devices The logic to configure a network interface for kernel IP auto-configuration is very simplistic, and does not handle the case where a device is stacked onto another such as with DSA. This causes the kernel not to open and configure the master network device in a DSA switch tree, and therefore slave network devices using this master network devices as conduit device cannot be open. This restriction comes from a check in net/dsa/slave.c, which is basically checking the master netdev flags for IFF_UP and returns -ENETDOWN if it is not the case. Automatically bringing-up DSA master network devices allows DSA slave network devices to be used as valid interfaces for e.g: NFS root booting by allowing kernel IP autoconfiguration to succeed on these interfaces. On the reverse path, make sure we do not attempt to close a DSA-enabled device as this would implicitely prevent the slave DSA network device from operating. Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller --- net/ipv4/ipconfig.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c index 7fa18bc7e47f..b26376ef87f6 100644 --- a/net/ipv4/ipconfig.c +++ b/net/ipv4/ipconfig.c @@ -209,9 +209,9 @@ static int __init ic_open_devs(void) last = &ic_first_dev; rtnl_lock(); - /* bring loopback device up first */ + /* bring loopback and DSA master network devices up first */ for_each_netdev(&init_net, dev) { - if (!(dev->flags & IFF_LOOPBACK)) + if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev)) continue; if (dev_change_flags(dev, dev->flags | IFF_UP) < 0) pr_err("IP-Config: Failed to open %s\n", dev->name); @@ -306,7 +306,7 @@ static void __init ic_close_devs(void) while ((d = next)) { next = d->next; dev = d->dev; - if (dev != ic_dev) { + if (dev != ic_dev && !netdev_uses_dsa(dev)) { DBG(("IP-Config: Downing %s\n", dev->name)); dev_change_flags(dev, d->flags); } -- 2.20.1