DBLFAULT_STACK_SIZE
static char dblfault_stack[DBLFAULT_STACK_SIZE] __aligned(16);
np = ((struct nmi_pcpu *)&doublefault_stack[DBLFAULT_STACK_SIZE]) - 1;
doublefault_stack = kmem_malloc(DBLFAULT_STACK_SIZE,
pmap_pti_add_kva_locked(va - DBLFAULT_STACK_SIZE, va, false);