_L_SR
pcb->pcb_context.val[_L_SR] = MIPS_SR_INT_IE
pcb->pcb_context.val[_L_SR] |= MIPS_SR_KX;
pcb->pcb_context.val[_L_SR] |= MIPS_SR_KX | MIPS_SR_UX;
KASSERT(pcb2->pcb_context.val[_L_SR] & MIPS_SR_KX);
KASSERTMSG(pcb2->pcb_context.val[_L_SR] & MIPS_SR_INT_IE,
pcb2->pcb_context.val[_L_SR]);
pcb0->pcb_context.val[_L_SR] = PSL_LOWIPL; /* SR */