DCPU_WANT_BT
kgdb_info[cpu].exception_state |= DCPU_WANT_BT;
while (kgdb_info[cpu].exception_state & DCPU_WANT_BT)
} else if (kgdb_info[cpu].exception_state & DCPU_WANT_BT) {
kgdb_info[cpu].exception_state &= ~DCPU_WANT_BT;