VCPU_EXREG_CR0
!kvm_register_is_available(vcpu, VCPU_EXREG_CR0))
kvm_x86_call(cache_reg)(vcpu, VCPU_EXREG_CR0);
case VCPU_EXREG_CR0:
kvm_register_mark_available(vcpu, VCPU_EXREG_CR0);
(1 << VCPU_EXREG_CR0) | \