USERSTACK          91 kernel/exec.c    if ((sz1 = uvmalloc(pagetable, sz, sz + (USERSTACK + 1) * PGSIZE, PTE_W)) ==
USERSTACK          95 kernel/exec.c    uvmclear(pagetable, sz - (USERSTACK + 1) * PGSIZE);
USERSTACK          97 kernel/exec.c    stackbase = sp - USERSTACK * PGSIZE;
USERSTACK        2450 user/usertests.c     sp -= USERSTACK * PGSIZE;