Pvm

pi-sbx keeps Pi on the host and runs its built-in shell and filesystem tools inside a Docker SBX microVM. Workspace changes remain visible on the host. PVM (Pagetable-based Virtual Machine) lets us run these microVMs inside an x86_64 Linux VM without exposed VMX/SVM or nested virtualization. It still provides the /dev/kvm interface used by SBX. First, install and boot the PVM host kernel from Porting PVM to Linux 7.2, including its pti=off boot setting. You also need an SBX-compatible PVM guest kernel, saved as vmlinux below. ...

The original PVM kernel tree was based on Linux 6.12.x, while current Linux master had reached 7.2. This note records the commands I used to build, package, and boot the forward port. The resulting tree is available in the pvm-720 branch. Update: Rebased to 7.3.x now! PVM in short PVM (Pagetable-based Virtual Machine) is a KVM guest hypervisor designed for running nested workloads without requiring VMX or SVM. Essentially native or nested virtualization HW functionality is NOT required! It uses a small shared region for privilege transitions and efficient shadow page tables for memory virtualization. The design is described in the SOSP '23 paper PVM: Efficient Shadow Paging for Deploying Secure Containers in Cloud-native Environments. The original code is in the virt-pvm/linux repository. ...