u/RickWangRD

Hi everyone,

I encountered an issue when trying to perform a live migration for an instance with PCI passthrough.

Environment:

• OS: Ubuntu 24.04
• OpenStack Version: Epoxy (deployed via Kolla-Ansible)
• Hardware: Intel X710 NIC (PCI Passthrough)
• libvirtd version: 10.0.0
• QEMU emulator version 8.2.2 (Debian 1:8.2.2+ds-0ubuntu1.13)
• Documentation Followed: https://docs.openstack.org/nova/2025.2/admin/pci-passthrough.html

Issue Description: I can successfully spawn instances with PCI passthrough on every compute node without any issues. However, when I attempt to live migrate the instance via the Dashboard (Horizon), the process fails.

I found the following error messages in the nova-compute logs:

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2026-05-13 15:29:41.668 7 INFO nova.compute.rpcapi [None req-3573ed71-a795-4673-8cec-75c834b352e7 1c048bb1747e49fca293e1b9d8c2e854 83b1a4951d534fc6980f7dda61cebeaf - - default default] Automatically selected compute RPC version 6.4 from minimum service version 68

2026-05-13 15:29:50.223 7 INFO nova.compute.manager [None req-3573ed71-a795-4673-8cec-75c834b352e7 1c048bb1747e49fca293e1b9d8c2e854 83b1a4951d534fc6980f7dda61cebeaf - - default default] [instance: 2e860bab-d6cd-49e7-a72b-b813537d2f33] Took 9.07 seconds for pre_live_migration on destination host ecc-edge-compute01.

2026-05-13 15:29:50.498 7 WARNING nova.compute.manager [req-585626ca-e41f-4522-97b5-dbe2d3179410 req-c44b83bf-65da-43d1-b2d0-60a39583a4db d73bc2af52f2481ba54878eaabd331aa e28d9231c61e48259e7fa2211e3b65fe - - default default] [instance: 2e860bab-d6cd-49e7-a72b-b813537d2f33] Received unexpected event network-vif-plugged-aef81b5a-d016-4286-a4b0-e07213f9f86c for instance with vm_state active and task_state migrating.

2026-05-13 15:29:51.301 7 ERROR nova.virt.libvirt.driver [None req-3573ed71-a795-4673-8cec-75c834b352e7 1c048bb1747e49fca293e1b9d8c2e854 83b1a4951d534fc6980f7dda61cebeaf - - default default] [instance: 2e860bab-d6cd-49e7-a72b-b813537d2f33] Live Migration failure: Requested operation is not valid: cannot migrate domain: 0000:3b:00.0: VFIO migration is not supported in kernel: libvirt.libvirtError: Requested operation is not valid: cannot migrate domain: 0000:3b:00.0: VFIO migration is not supported in kernel

2026-05-13 15:29:51.760 7 ERROR nova.virt.libvirt.driver [None req-3573ed71-a795-4673-8cec-75c834b352e7 1c048bb1747e49fca293e1b9d8c2e854 83b1a4951d534fc6980f7dda61cebeaf - - default default] [instance: 2e860bab-d6cd-49e7-a72b-b813537d2f33] Migration operation has aborted

2026-05-13 15:29:52.297 7 INFO nova.compute.manager [None req-3573ed71-a795-4673-8cec-75c834b352e7 1c048bb1747e49fca293e1b9d8c2e854 83b1a4951d534fc6980f7dda61cebeaf - - default default] [instance: 2e860bab-d6cd-49e7-a72b-b813537d2f33] Swapping old allocation on dict_keys(['0908272f-fb28-4fcd-b888-faed3ebe008d']) held by migration c544f968-a817-43c0-9ad8-ce31da02715a for instance

2026-05-13 15:29:57.274 7 WARNING nova.compute.manager [req-d154f165-86f0-4461-825f-5d6732f75dec req-93ca2943-9913-4eb8-938d-b7b3b352d741 d73bc2af52f2481ba54878eaabd331aa e28d9231c61e48259e7fa2211e3b65fe - - default default] [instance: 2e860bab-d6cd-49e7-a72b-b813537d2f33] Received unexpected event network-vif-unplugged-aef81b5a-d016-4286-a4b0-e07213f9f86c for instance with vm_state active and task_state None.

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Does anyone have any ideas or suggestions on why this might be happening?

Thanks in advance for your help!