Description of problem:
The port was initially created with vnic type direct and was changed with 'openstack port set --vnic-type macvtap $PORTID' after creation. The nova_compute container was restarted manually and gets into a restart loop.

Customer managed to make the change work after rebooting the compute node.
Customer wants to know if this behaviour is expected or if there's a way to do this chnage w/o rebooting the compute node.

[stack@qasite1-compute002 ~]$ sudo docker exec nova_libvirt virsh dumpxml instance-00016b53
<domain type='kvm' id='70'>
<name>instance-00016b53</name>
<uuid>4ef19e36-1af5-4a51-95d4-c50bce2236b7</uuid>
<metadata>
<nova:instance xmlns:nova="http://openstack.org/xmlns/libvirt/nova/1.0">
<nova:package version="17.0.13-36.el7ost"/>
<nova:name>simon-test</nova:name>
<nova:creationTime>2022-06-29 14:53:40</nova:creationTime>
<nova:flavor name="m1.tiny">
<nova:memory>512</nova:memory>
<nova:disk>1</nova:disk>
<nova:swap>0</nova:swap>
<nova:ephemeral>0</nova:ephemeral>
<nova:vcpus>1</nova:vcpus>
</nova:flavor>
<nova:owner>
<nova:user uuid="d44542c3921f44b2a56ba0539b89a64f">simon-test</nova:user>
<nova:project uuid="70d6aea90ccd4ed6bfee2451b4965508">admin</nova:project>
</nova:owner>
</nova:instance>
</metadata>
<memory unit='KiB'>524288</memory>
<currentMemory unit='KiB'>524288</currentMemory>
<vcpu placement='static' cpuset='1-17,19-35,37-53,55-71'>1</vcpu>
<cputune>
<shares>1024</shares>
</cputune>
<resource>
<partition>/machine</partition>
</resource>
<sysinfo type='smbios'>
<system>
<entry name='manufacturer'>Red Hat</entry>
<entry name='product'>OpenStack Compute</entry>
<entry name='version'>17.0.13-36.el7ost</entry>
<entry name='serial'>39373638-3935-584d-5138-333730323852</entry>
<entry name='uuid'>4ef19e36-1af5-4a51-95d4-c50bce2236b7</entry>
<entry name='family'>Virtual Machine</entry>
</system>
</sysinfo>
<os>
<type arch='x86_64' machine='pc-i440fx-rhel7.6.0'>hvm</type>
<boot dev='hd'/>
<smbios mode='sysinfo'/>
</os>
<features>
<acpi/>
<apic/>
</features>
<cpu mode='custom' match='exact' check='full'>
<model fallback='forbid'>Skylake-Server-IBRS</model>
<vendor>Intel</vendor>
<topology sockets='1' cores='1' threads='1'/>
<feature policy='require' name='ss'/>
<feature policy='require' name='hypervisor'/>
<feature policy='require' name='tsc_adjust'/>
<feature policy='require' name='clflushopt'/>
<feature policy='require' name='pku'/>
<feature policy='require' name='md-clear'/>
<feature policy='require' name='stibp'/>
<feature policy='require' name='ssbd'/>
<feature policy='require' name='ibpb'/>
</cpu>
<clock offset='utc'>
<timer name='pit' tickpolicy='delay'/>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='hpet' present='no'/>
</clock>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<devices>
<emulator>/usr/libexec/qemu-kvm</emulator>
<disk type='block' device='disk'>
<driver name='qemu' type='raw' cache='none' io='native' discard='unmap'/>
<source dev='/dev/sdd'/>
<backingStore/>
<target dev='vda' bus='virtio'/>
<serial>1d31be17-2616-4b4f-a020-cc45207e2bb6</serial>
<alias name='virtio-disk0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</disk>
<controller type='usb' index='0' model='piix3-uhci'>
<alias name='usb'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pci-root'>
<alias name='pci.0'/>
</controller>
<interface type='hostdev' managed='yes'>
<mac address='fa:16:3e:82:e0:fc'/>
<driver name='vfio'/>
<source>
<address type='pci' domain='0x0000' bus='0x37' slot='0x04' function='0x3'/>
</source>
<vlan>
<tag id='3969'/>
</vlan>
<alias name='hostdev0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
</interface>
<serial type='pty'>
<source path='/dev/pts/0'/>
<log file='/var/lib/nova/instances/4ef19e36-1af5-4a51-95d4-c50bce2236b7/console.log' append='off'/>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
<alias name='serial0'/>
</serial>
<console type='pty' tty='/dev/pts/0'>
<source path='/dev/pts/0'/>
<log file='/var/lib/nova/instances/4ef19e36-1af5-4a51-95d4-c50bce2236b7/console.log' append='off'/>
<target type='serial' port='0'/>
<alias name='serial0'/>
</console>
<input type='tablet' bus='usb'>
<alias name='input0'/>
<address type='usb' bus='0' port='1'/>
</input>
<input type='mouse' bus='ps2'>
<alias name='input1'/>
</input>
<input type='keyboard' bus='ps2'>
<alias name='input2'/>
</input>
<graphics type='vnc' port='5900' autoport='yes' listen='192.168.20.103' keymap='en-us'>
<listen type='address' address='192.168.20.103'/>
</graphics>
<video>
<model type='cirrus' vram='16384' heads='1' primary='yes'/>
<alias name='video0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
</video>
<memballoon model='virtio'>
<stats period='10'/>
<alias name='balloon0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
</memballoon>
</devices>
<seclabel type='dynamic' model='selinux' relabel='yes'>
<label>system_u:system_r:svirt_t:s0:c515,c780</label>
<imagelabel>system_u:object_r:svirt_image_t:s0:c515,c780</imagelabel>
</seclabel>
<seclabel type='dynamic' model='dac' relabel='yes'>
<label>+107:+107</label>
<imagelabel>+107:+107</imagelabel>
</seclabel>
</domain>

[stack@qasite1-compute002 ~]$
(overcloud) [stack@qasite1-director ~]$ openstack server show 4ef19e36-1af5-4a51-95d4-c50bce2236b7
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(overcloud) [stack@qasite1-director ~]$ openstack network show simon-sriov-0-1-test
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(overcloud) [stack@qasite1-director ~]$ openstack port list --network simon-sriov-0-1-test
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(overcloud) [stack@qasite1-director ~]$ openstack port show f6c2d743-6f81-4dc8-981a-e5d55fc8a487
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How reproducible:
Customer reproduced this in a Q&A environment.
sosreport of the compute node is attached to the support case.