Re: VRF/IPv4/ARP: unregister_netdevice waiting for dev to become free -> Who's responsible for releasing dst_entry created by ip_route_input_noref?

On 6/5/21 11:16 AM, Oliver Herms wrote:

Hi everyone,

I'm observing an device unregistration issue when I try to delete a VRF interface after using the VRF.
The issue is reproducible on 5.12.9, 5.10.24, 5.11.0-18 (debian).

Here are the steps to reproduce the issue:

ip addr add 10.0.0.1/32 dev lo
ip netns add test-ns
ip link add veth-outside type veth peer name veth-inside
ip link add vrf-100 type vrf table 1100
ip link set veth-outside master vrf-100
ip link set veth-inside netns test-ns
ip link set veth-outside up
ip link set vrf-100 up
ip route add 10.1.1.1/32 dev veth-outside table 1100
ip netns exec test-ns ip link set veth-inside up
ip netns exec test-ns ip addr add 10.1.1.1/32 dev veth-inside
ip netns exec test-ns ip route add 10.0.0.1/32 dev veth-inside
ip netns exec test-ns ip route add default via 10.0.0.1
ip netns exec test-ns ping 10.0.0.1 -c 1 -i 1
sleep 10
ip link set veth-outside nomaster
ip link set vrf-100 down
ip link delete vrf-100 <= Never returns

thanks for the quick reproducer; I will take a look.