A.18. Troubleshooting SR-IOV
This section contains solutions for problems which may affect SR-IOV. If you need additional help, see Section 16.2.4, “Setting PCI device assignment from a pool of SR-IOV virtual functions”.
- Error starting the guest
- When starting a configured virtual machine, an error occurs as follows:
virsh start testerror: Failed to start domain test error: Requested operation is not valid: PCI device 0000:03:10.1 is in use by domain rhel7This error is often caused by a device that is already assigned to another guest or to the host itself.
- Error migrating, saving, or dumping the guest
- Attempts to migrate and dump the virtual machine cause an error similar to the following:
virsh dump rhel7/tmp/rhel7.dumperror: Failed to core dump domain rhel7 to /tmp/rhel7.dump error: internal error: unable to execute QEMU command 'migrate': State blocked by non-migratable device '0000:00:03.0/vfio-pci'Because device assignment uses hardware on the specific host where the virtual machine was started, guest migration and save are not supported when device assignment is in use. Currently, the same limitation also applies to core-dumping a guest; this may change in the future. It is important to note that QEMU does not currently support migrate, save, and dump operations on guest virtual machines with PCI devices attached, unless the
--memory-onlyoption is specified. Currently, it only can support these actions with USB devices. Work is currently being done to improve this in the future.