kvm_mmu_root_info
((struct kvm_mmu_root_info) { .pgd = INVALID_PAGE, .hpa = INVALID_PAGE })
struct kvm_mmu_root_info root;
struct kvm_mmu_root_info prev_roots[KVM_MMU_NUM_PREV_ROOTS];
static inline bool is_root_usable(struct kvm_mmu_root_info *root, gpa_t pgd,
struct kvm_mmu_root_info *cached_root;