HWINTR_BLOCKING
if (gi & HWINTR_BLOCKING) {
gi &= ~HWINTR_BLOCKING;
if ((gi & (HWINTR_BLOCKING | NMI_BLOCKING)) == 0) {
if (gi & HWINTR_BLOCKING) {
*retval = (gi & HWINTR_BLOCKING) ? 1 : 0;
gi &= ~HWINTR_BLOCKING;