preallocate_pgd_pages_range
preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc");
preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules");
preallocate_pgd_pages_range(VMEMMAP_START, VMEMMAP_END, "vmemmap");
preallocate_pgd_pages_range(PAGE_OFFSET, PAGE_END, "direct map");
preallocate_pgd_pages_range(KASAN_SHADOW_START, KASAN_SHADOW_END, "kasan");