Migrating a virtual machine that owns a resource such as a hardware device

摘要

A computing device has first and second virtual machines (VMs) and a resource assigned to the first VM. Each access request for the resource is forwarded thereto until the first VM is to be saved or migrated. Thereafter, each access request is forwarded to a holding queue. When the resource has acted upon all access requests forwarded thereto, the resource is reassigned to the second VM, and each access request at the holding queue is forwarded to the second VM and then the resource. Thus, all access requests for the resource are acted upon by the resource even after the resource is removed from the first VM and assigned to the second VM, and the save or migrate of the first VM can thereafter be completed.

主权项

1. A method with regard to a computing system comprising:
forwarding an access request from a resource stack to be queued at a first port on a first virtual machine (VM), each access request as queued at the first port being further forwarded in turn to the resource to be acted upon by such resource; forwarding at least one subsequent access request from the resource stack to be queued at a second port on the first virtual machine; and after the resource has acted upon substantially all access requests queued at and forwarded by the first port: assigning the resource to a second VM such that the second VM controls the resource; and forwarding access request queued at the second port to the resource by way of the second VM to be acted upon by the resource such that the at least one subsequent access request from the resource stack of the first VM are acted upon by the resource in turn after the resource is removed from the first VM and assigned to the second VM; and migrating the first VM to a different computing device after assigning the resource to the second VM.