gdt                 6 proc.h           struct segdesc gdt[NSEGS];   // x86 global descriptor table
gdt                25 vm.c             c->gdt[SEG_KCODE] = SEG(STA_X|STA_R, 0, 0xffffffff, 0);
gdt                26 vm.c             c->gdt[SEG_KDATA] = SEG(STA_W, 0, 0xffffffff, 0);
gdt                27 vm.c             c->gdt[SEG_UCODE] = SEG(STA_X|STA_R, 0, 0xffffffff, DPL_USER);
gdt                28 vm.c             c->gdt[SEG_UDATA] = SEG(STA_W, 0, 0xffffffff, DPL_USER);
gdt                29 vm.c             lgdt(c->gdt, sizeof(c->gdt));
gdt               167 vm.c             mycpu()->gdt[SEG_TSS] = SEG16(STS_T32A, &mycpu()->ts,
gdt               169 vm.c             mycpu()->gdt[SEG_TSS].s = 0;