Explore nested virtualization on the IBM POWER9 processor in this 46-minute conference talk from linux.conf.au. Dive into the rationale, implementation details, and challenges of developing software support for running virtual machines within virtual machines. Learn about the changes made to KVM and QEMU, the current state of the project, and future work. Discover the increased hardware support for nested virtualization in POWER9, understand the entry path and memory management processes, and compare KVM-PR and KVM-HV approaches. Gain insights into nested guest address translation, partition scoped PTE generation, and migration of nested guests. Explore performance considerations and find out just how deep nesting can go. Get practical information on how to use this feature and learn about ongoing development efforts.