On Wed, Mar 20, 2019 at 09:37:44AM +0100, Cédric Le Goater wrote: > The state of the thread interrupt management registers needs to be > collected for migration. These registers are cached under the > 'xive_saved_state.w01' field of the VCPU when the VPCU context is > pulled from the HW thread. An OPAL call retrieves the backup of the > IPB register in the underlying XIVE NVT structure and merges it in the > KVM state. Since you're adding a new one_reg identifier value, you need to update the list in Documentation/virtual/kvm/api.txt. Paul.