switch (aarch64_io.iov_len) {
case sizeof(aarch64_regs):
/* We are in 64-bit mode */
scno = aarch64_regs.regs[8];
update_personality(tcp, 1);
break;
case sizeof(arm_regs):
/* We are in 32-bit mode */
/* Note: we don't support OABI, unlike 32-bit ARM build */
scno = arm_regs.ARM_r7;
scno = shuffle_scno(scno);
update_personality(tcp, 0);
break;
}