Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:

 - a few hot fixes

 - ocfs2 updates

 - almost all of -mm (slab-generic, slab, slub, kmemleak, kasan,
   cleanups, debug, pagecache, memcg, gup, pagemap, memory-hotplug,
   sparsemem, vmalloc, initialization, z3fold, compaction, mempolicy,
   oom-kill, hugetlb, migration, thp, mmap, madvise, shmem, zswap,
   zsmalloc)

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits)
  mm/zsmalloc.c: fix a -Wunused-function warning
  zswap: do not map same object twice
  zswap: use movable memory if zpool support allocate movable memory
  zpool: add malloc_support_movable to zpool_driver
  shmem: fix obsolete comment in shmem_getpage_gfp()
  mm/madvise: reduce code duplication in error handling paths
  mm: mmap: increase sockets maximum memory size pgoff for 32bits
  mm/mmap.c: refine find_vma_prev() with rb_last()
  riscv: make mmap allocation top-down by default
  mips: use generic mmap top-down layout and brk randomization
  mips: replace arch specific way to determine 32bit task with generic version
  mips: adjust brk randomization offset to fit generic version
  mips: use STACK_TOP when computing mmap base address
  mips: properly account for stack randomization and stack guard gap
  arm: use generic mmap top-down layout and brk randomization
  arm: use STACK_TOP when computing mmap base address
  arm: properly account for stack randomization and stack guard gap
  arm64, mm: make randomization selected by generic topdown mmap layout
  arm64, mm: move generic mmap layout functions to mm
  arm64: consider stack randomization for mmap base only when necessary
  ...

3 files changed, 14 insertions, 5 deletions

diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab
index 29601d93a1c2..ed35833ad7f0 100644
--- a/Documentation/ABI/testing/sysfs-kernel-slab
+++ b/Documentation/ABI/testing/sysfs-kernel-slab
@@ -429,10 +429,15 @@ KernelVersion:	2.6.22
 Contact:	Pekka Enberg <penberg@cs.helsinki.fi>,
 		Christoph Lameter <cl@linux-foundation.org>
 Description:
-		The shrink file is written when memory should be reclaimed from
-		a cache.  Empty partial slabs are freed and the partial list is
-		sorted so the slabs with the fewest available objects are used
-		first.
+		The shrink file is used to reclaim unused slab cache
+		memory from a cache.  Empty per-cpu or partial slabs
+		are freed and the partial list is sorted so the slabs
+		with the fewest available objects are used first.
+		It only accepts a value of "1" on write for shrinking
+		the cache. Other input values are considered invalid.
+		Shrinking slab caches might be expensive and can
+		adversely impact other running applications.  So it
+		should be used with care.
 
 What:		/sys/kernel/slab/cache/slab_size
 Date:		May 2007
diff --git a/Documentation/admin-guide/cgroup-v1/memory.rst b/Documentation/admin-guide/cgroup-v1/memory.rst
index 41bdc038dad9..0ae4f564c2d6 100644
--- a/Documentation/admin-guide/cgroup-v1/memory.rst
+++ b/Documentation/admin-guide/cgroup-v1/memory.rst
@@ -85,8 +85,10 @@ Brief summary of control files.
  memory.oom_control		     set/show oom controls.
  memory.numa_stat		     show the number of memory usage per numa
 				     node
-
  memory.kmem.limit_in_bytes          set/show hard limit for kernel memory
+                                     This knob is deprecated and shouldn't be
+                                     used. It is planned that this be removed in
+                                     the foreseeable future.
  memory.kmem.usage_in_bytes          show current kernel memory allocation
  memory.kmem.failcnt                 show the number of kernel memory usage
 				     hits limits
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 254d8a369f32..944e03e29f65 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -809,6 +809,8 @@
 			enables the feature at boot time. By default, it is
 			disabled and the system will work mostly the same as a
 			kernel built without CONFIG_DEBUG_PAGEALLOC.
+			Note: to get most of debug_pagealloc error reports, it's
+			useful to also enable the page_owner functionality.
 			on: enable the feature
 
 	debugpat	[X86] Enable PAT debugging