Arm: virtualization
doc
virtualization支撑：isolation, high availability, workload balancing, sandboxing
type 1: Hypervisor上跑Guest OS；例如xen
type 2: Host OS上跑hypervisor，hypervisor上跑Guest OS；例如virtualbox, vmware, kvm
VMID & ASID
每个VM有它自己的ASID空间
VMID区分VM，ASID区分应用
System Memory Management Units (SMMUs)
SMMU, DMA都是可以直接访问Physical Address的。。。
Guest OS -> VA -> MMU -> IPA -> MMU -> PA
DMA -> IPA -> SMMU -> PA
virtualizing exceptions
GIC管所有Physical CPU, vCPU的中断
