DEFAULT_STACK_PGS
stack_size = vm->page_size == 4096 ? DEFAULT_STACK_PGS * vm->page_size :
nr_pages += nr_runnable_vcpus * DEFAULT_STACK_PGS;
stack_size = vm->page_size == 4096 ? DEFAULT_STACK_PGS * vm->page_size :
size_t stack_size = DEFAULT_STACK_PGS * getpagesize();
regs.gprs[15] = stack_vaddr + (DEFAULT_STACK_PGS * getpagesize()) - 160;
stack_vaddr = __vm_vaddr_alloc(vm, DEFAULT_STACK_PGS * getpagesize(),
stack_vaddr += DEFAULT_STACK_PGS * getpagesize();