Bug 1879352

This bug was initially created as a copy of Bug #1829272

I am copying this bug because: 
They are very similar.


Description of problem:
Hotplug nic can not get ip address after hotplug combination NICs. This issue is found via automation test.  Maybe manual test can't use 'fd' or other reason.  I can't reproduce it by manual test.  Hit this issue on RHEL7.5 RHEL7.6 RHEL7.7 and RHEL7.9 host. 


Version-Release number of selected component (if applicable):

For 7.9 
qemu-kvm-rhev-2.12.0-48.el7_9.1.x86_64 qemu-kvm-rhev-2.12.0-48.el7.x86_64-->fail
qemu-kvm-rhev-2.12.0-47.el7.x86_64 -->works

qemu-kvm-1.5.3-175.el7.1.x86_64 qemu-kvm-1.5.3-175.el7.x86_64 -->fail
qemu-kvm-1.5.3-174.el7.x86_64 -->works

For 7.8 
works(no found)

For 7.7 
qemu-kvm-1.5.3-167.el7_7.7.x86_64-amd qemu-kvm-rhev-2.12.0-33.el7_7.12.x86_64--fail

qemu-kvm-rhev-2.12.0-33.el7_7.11.x86_64-->works

For 7.6
qemu-kvm-rhev-2.12.0-18.el7_6.12.x86_64 qemu-kvm-1.5.3-160.el7_6.7.x86_64 qemu-kvm-1.5.3-160.el7_6.8.x86_64 -->fail

qemu-kvm-rhev-2.12.0-18.el7_6.11.x86_64 qemu-kvm-1.5.3-160.el7_6.6.x86_64-->works

For 7.5 
qemu-kvm-rhev-2.10.0-21.el7_5.10.x86_64 -->fail


How reproducible:
sometimes

Steps to Reproduce:
1. boot guest

2. hotplug NICs(like this, This only is part of steps)

{'execute': 'netdev_add', 'arguments': {'type': 'tap', 'id': 'a-8139'}, 'id': '8139-1'}
{'execute': 'device_add', 'arguments': {'addr': '0xb', 'netdev': 'a-8139', 'bus': 'pci.0', 'driver': 'rtl8139', 'mac': '9a:ae:3b:81:a6:b1', 'id': 'idlvje5y'}, 'id': '9l4q3lzd'}
{ "execute": "set_link","arguments": { "name": "a-8139","up": false } }

{'execute': 'netdev_add', 'arguments': {'type': 'tap', 'id': 'virtio-net'}, 'id': 'virtio-2'}
{'execute': 'device_add', 'arguments': {'addr': '0xc', 'netdev': 'virtio-net', 'bus': 'pci.0', 'driver': 'virtio-net-pci', 'mac': '9a:ae:3b:81:a6:b2', 'id': 'idefuwn1'}, 'id': 'ukdhjwv4'}
{ "execute": "set_link","arguments": { "name": "virtio-net","up": false } }

{'execute': 'netdev_add', 'arguments': {'type': 'tap', 'id': 'b-1000'}, 'id': '1000-1'}
{'execute': 'device_add', 'arguments': {'addr': '0xd', 'netdev': 'b-1000', 'bus': 'pci.0', 'driver': 'e1000', 'mac': '9a:ae:3b:81:a6:b3', 'id': 'idE8vPBI'}, 'id': 'N0GmWfSV'}

3. inside guest.
#dhclient -r
#dhclient ethx


Actual results:
cannot get valid ip

Expected results:
can get ip and ping succesfully


Additional info: