Merge branch 'akpm' (patches from Andrew)

Merge branch 'akpm' (patches from Andrew)

Merge fixes from Andrew Morton:
 "13 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  dma-mapping: avoid oops when parameter cpu_addr is null
  mm/hugetlb: use EOPNOTSUPP in hugetlb sysctl handlers
  memremap: check pfn validity before passing to pfn_to_page()
  mm, thp: fix migration of PTE-mapped transparent huge pages
  dax: check return value of dax_radix_entry()
  ocfs2: fix return value from ocfs2_page_mkwrite()
  arm64: kasan: clear stale stack poison
  sched/kasan: remove stale KASAN poison after hotplug
  kasan: add functions to clear stack poison
  mm: fix mixed zone detection in devm_memremap_pages
  list: kill list_force_poison()
  mm: __delete_from_page_cache show Bad page if mapped
  mm/hugetlb: hugetlb_no_page: rate-limit warning message