GNMITSS_SEL
setsegment(&ci->ci_gdt[GNMITSS_SEL].sd, ci->ci_nmi_tss,
setsegment(&cpu_info_primary.ci_gdt[GNMITSS_SEL].sd,
setgate(&idt[ 2], NULL, 0, SDT_SYSTASKGT, SEL_KPL, GNMITSS_SEL);