On 4/20/17 8:39 AM, Robert Shearman wrote: > On 20/04/17 15:21, David Ahern wrote: >> On 4/20/17 6:58 AM, Robert Shearman wrote: >>> David reported that doing the following: >>> >>> ip li add red type vrf table 10 >>> ip link set dev eth1 vrf red >>> ip addr add 127.0.0.1/8 dev red >>> ip link set dev eth1 up >>> ip li set red up >>> ping -c1 -w1 -I red 127.0.0.1 >>> ip li del red >>> >>> results in a hang with this message: >>> >>> unregister_netdevice: waiting for red to become free. Usage count >>> = 1 >> >> I think you misunderstood my comment. The above works fine today. There >> is no bug with refcnts. >> >> It breaks with your patches wanting to use a VRF device with the main >> table (254). > > That doesn't seem to match with my experience. I can reproduce this on > the net tree with the listed commands and the behaviour matches what I > see in the code.
Our mileage varies: root@kenny-jessie3:~# ip li add red type vrf table 10 root@kenny-jessie3:~# ip link set dev eth1 vrf red root@kenny-jessie3:~# ip addr add 127.0.0.1/8 dev red root@kenny-jessie3:~# ip link set dev eth1 up root@kenny-jessie3:~# ip li set red up root@kenny-jessie3:~# ping -c1 -w1 -I red 127.0.0.1 PING 127.0.0.1 (127.0.0.1) from 127.0.0.1 red: 56(84) bytes of data. 64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.059 ms --- 127.0.0.1 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.059/0.059/0.059/0.000 ms root@kenny-jessie3:~# ip li del red root@kenny-jessie3:~# uname -a Linux kenny-jessie3 4.11.0-rc6+ #8 SMP Wed Apr 19 11:53:48 PDT 2017 x86_64 GNU/Linux The above is one of many tests I run and never hit a problem deleting a VRF device. dst's attached to fnhe_rth_output and fnhe_rth_input appear to be properly flushed and device references released when the device is deleted (NETDEV_DOWN and then NETDEV_UNREGISTER). Can you send me your kernel config and "sysctl -a --pattern 'net.ipv4'"? Perhaps you have something enabled I don't.
