Merge branch 'akpm' (patches from Andrew)

Merge more fixes from Andrew Morton:
 "The usual shower of hotfixes and some followups to the recently merged
  page_owner enhancements"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/memory-failure: poison read receives SIGKILL instead of SIGBUS if mmaped more than once
  mm/slab.c: fix kernel-doc warning for __ksize()
  xarray.h: fix kernel-doc warning
  bitmap.h: fix kernel-doc warning and typo
  fs/fs-writeback.c: fix kernel-doc warning
  fs/libfs.c: fix kernel-doc warning
  fs/direct-io.c: fix kernel-doc warning
  mm, compaction: fix wrong pfn handling in __reset_isolation_pfn()
  mm, hugetlb: allow hugepage allocations to reclaim as needed
  lib/test_meminit: add a kmem_cache_alloc_bulk() test
  mm/slub.c: init_on_free=1 should wipe freelist ptr for bulk allocations
  lib/generic-radix-tree.c: add kmemleak annotations
  mm/slub: fix a deadlock in show_slab_objects()
  mm, page_owner: rename flag indicating that page is allocated
  mm, page_owner: decouple freeing stack trace from debug_pagealloc
  mm, page_owner: fix off-by-one error in __set_page_owner_handle()