Merge branch 'akpm' (patches from Andrew)

Merge fixes from Andrew Morton:
 "6 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  lib/Kconfig.debug: fix some messed up configurations
  mm: vmscan: protect shrinker idr replace with CONFIG_MEMCG
  kasan: don't assume percpu shadow allocations will succeed
  kasan: use apply_to_existing_page_range() for releasing vmalloc shadow
  mm/memory.c: add apply_to_existing_page_range() helper
  kasan: fix crashes on access to memory mapped by vm_map_ram()