Description of problem:
On 20.E, openvswitch 2.9 running on rhel 7.8 failed to handle the port type "ip6gre", we cannot create an ip6gre type port so cannot create ipv6 gre tunnel.
Following errors pop up:
Error detected while setting up 'gre1': could not open network device gre1 (Address family not supported by protocol).  See ovs-vswitchd log for details.


Version-Release number of selected component (if applicable):
FDP: 20.E
OVS: openvswitch-2.9.0-131.el7fdp.x86_64.rpm
RHEL: RHEL-7.8-updates-20200616.0

How reproducible:
always

Steps to Reproduce:
1. setup ipv6 address on both systems
2. create ovs bridge: ovs-vsctl add-br br0
3. add ipv6 gre tunnel: ovs-vsctl add-port br0 gre1 -- set interface gre1 type=ip6gre options:remote_ip=${peer_ipv6_address} options:local_ip=${local_ipv6_address}

Actual results:

Error popped up: 
Error detected while setting up 'gre1': could not open network device gre1 (Address family not supported by protocol).  See ovs-vswitchd log for details.
log in /var/log/openvswitch/ovs-vswitchd.log:
2020-07-07T03:28:05.300Z|00032|netdev|WARN|could not create netdev gre1 of unknown type ip6gre
2020-07-07T03:28:05.300Z|00033|bridge|WARN|could not open network device gre1 (Address family not supported by protocol)

Expected results:
Successfully configure ipv6 gre tunnel

Additional info: