SP_EL2
write_sysreg(__vcpu_sys_reg(vcpu, SP_EL2), sp_el1);
__vcpu_assign_sys_reg(vcpu, SP_EL2, read_sysreg(sp_el1));
mod = __vcpu_sys_reg(vcpu, SP_EL2);
EL2_REG(SP_EL2, NULL, reset_unknown, 0),
SYS_REG(SP_EL2),