kvm_get_vtcr
u64 kvm_get_vtcr(u64 mmfr0, u64 mmfr1, u32 phys_shift);
host_mmu.arch.mmu.vtcr = kvm_get_vtcr(id_aa64mmfr0_el1_sys_val,
mmu->vtcr = kvm_get_vtcr(mmfr0, mmfr1, phys_shift);