Live Migration of Virtual Machines with USB pass-through devices

BBB-Link: https://bbb.tu-dresden.de/b/mat-xin-oyh-xzn

Presentation Language: English

Live migration allows a virtual machine (VM) to move between different instances of VMMs with minimal interruption, making it useful for system maintenance and improving availability. However, migrating a VM with physical USB devices introduces additional challenges, as both the state of the virtual USB controller and access to the physical device need to be handled. This becomes more complicated when the USB controller runs in a separate process outside the virtual machine monitor (VMM), since its state is not directly managed by the VMM. This talk examines the current migration support in QEMU, a widely used virtualization platform, and Cloud Hypervisor, a lightweight VMM designed for cloud workloads. It discusses the challenges of migrating external USB devices and presents a proposed approach to extending Cloud Hypervisor to coordinate migration with an external USB backend. It also explores possible ways to reduce device interruptions during migration.