From: Xiao Liang shaw.leon@gmail.com Date: Thu, 13 Feb 2025 17:55:32 +0800
On Thu, Feb 13, 2025 at 4:37 PM Xiao Liang shaw.leon@gmail.com wrote:
On Thu, Feb 13, 2025 at 3:05 PM Kuniyuki Iwashima kuniyu@amazon.com wrote:
[...]
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 863852abe8ea..108600dc716f 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -1498,7 +1498,8 @@ static int ip6gre_tunnel_init_common(struct net_device *dev) tunnel = netdev_priv(dev);
tunnel->dev = dev;
tunnel->net = dev_net(dev);
if (!tunnel->net)tunnel->net = dev_net(dev);Same question as patch 5 for here and other parts. Do we need this check and assignment ?
ip6gre_newlink_common -> nt->net = dev_net(dev) -> register_netdevice -> ndo_init / ip6gre_tunnel_init() -> ip6gre_tunnel_init_common -> tunnel->net = dev_net(dev)
Will remove this line.
However, fb tunnel of ip6_tunnel, ip6_vti and sit can have tunnel->net == NULL here. Take ip6_tunnel for example:
ip6_tnl_init_net() -> ip6_fb_tnl_dev_init() -> register_netdev() -> register_netdevice() -> ip6_tnl_dev_init()
This code path (including ip6_fb_tnl_dev_init()) doesn't set tunnel->net. But for ip6_gre, ip6gre_fb_tunnel_init() does.
Ah, okay. Then, let's set net in a single place, which would be better than spreading net assignment and adding null check in ->ndo_init(), and maybe apply the same to IPv4 tunnels ?