Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:

 - "fork: unconditionally clear stack on fork" is a non-bugfix which got
   lost during the merge window - performance concerns appear to have
   been adequately addressed.

 - and a bunch of fixes

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/filemap.c: fix NULL pointer in page_cache_tree_insert()
  mm: memcg: add __GFP_NOWARN in __memcg_schedule_kmem_cache_create()
  fs, elf: don't complain MAP_FIXED_NOREPLACE unless -EEXIST error
  kexec_file: do not add extra alignment to efi memmap
  proc: fix /proc/loadavg regression
  proc: revalidate kernel thread inodes to root:root
  autofs: mount point create should honour passed in mode
  MAINTAINERS: add personal addresses for Sascha and Uwe
  kasan: add no_sanitize attribute for clang builds
  rapidio: fix rio_dma_transfer error handling
  mm: enable thp migration for shmem thp
  writeback: safer lock nesting
  mm, pagemap: fix swap offset value for PMD migration entry
  mm: fix do_pages_move status handling
  fork: unconditionally clear stack on fork