VPP sometimes a recursive error may occur
To reproduce, set this steps several times (I tried 5 times)
```
set vpp settings interface eth1 driver 'dpdk'
set vpp interfaces gre gre2 remote '192.0.2.25'
set vpp interfaces gre gre2 source-address '192.0.2.1'
set vpp interfaces gre gre2 kernel-interface 'vpptun12'
set vpp kernel-interfaces vpptun12 address '10.0.0.0/31'
commit && ip link show
delete vpp
commit && ip link show
```
The journalctl log attached
{F7970522}
In this step commit hung
```
vyos@r16# set vpp interfaces gre gre2 remote '192.0.2.25'
[edit]
vyos@r16# set vpp interfaces gre gre2 source-address '192.0.2.1'
[edit]
vyos@r16# set vpp interfaces gre gre2 kernel-interface 'vpptun12'
[edit]
vyos@r16# set vpp kernel-interfaces vpptun12 address '10.0.0.0/31'
[edit]
vyos@r16# commit && ip link show
```
process:
```
vyos@r16:~$ ps ax | grep commit
4471 pts/1 S+ 0:00 /opt/vyatta/sbin/my_commit
4696 pts/0 S+ 0:00 grep commit
vyos@r16:~$
```
NOTE: I increased priority `305` => `308` for the `vpp_kernel-interface` while testing.
```
vyos@r16:~$ /usr/libexec/vyos/priority.py | grep vpp
295 vpp.py ['vpp']
304 vpp_interfaces_bonding.py ['vpp', 'interfaces', 'bonding']
305 vpp_interfaces_gre.py ['vpp', 'interfaces', 'gre']
305 vpp_interfaces_ipip.py ['vpp', 'interfaces', 'ipip']
305 vpp_interfaces_loopback.py ['vpp', 'interfaces', 'loopback']
305 vpp_interfaces_vxlan.py ['vpp', 'interfaces', 'vxlan']
305 vpp_interfaces_xconnect.py ['vpp', 'interfaces', 'xconnect']
307 vpp_interfaces_bridge.py ['vpp', 'interfaces', 'bridge']
308 vpp_kernel-interfaces.py ['vpp', 'kernel-interfaces']
vyos@r16:~$
```