Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2 updates

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
  memory hotplug: fix comments when adding section
  mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
  mm: simplify nodemask printing
  mm,oom_reaper: remove pointless kthread_run() error check
  mm/page_ext.c: check if page_ext is not prepared
  writeback: remove unused function parameter
  mm: do not rely on preempt_count in print_vma_addr
  mm, sparse: do not swamp log with huge vmemmap allocation failures
  mm/hmm: remove redundant variable align_end
  mm/list_lru.c: mark expected switch fall-through
  mm/shmem.c: mark expected switch fall-through
  mm/page_alloc.c: broken deferred calculation
  mm: don't warn about allocations which stall for too long
  fs: fuse: account fuse_inode slab memory as reclaimable
  mm, page_alloc: fix potential false positive in __zone_watermark_ok
  mm: mlock: remove lru_add_drain_all()
  mm, sysctl: make NUMA stats configurable
  shmem: convert shmem_init_inodecache() to void
  Unify migrate_pages and move_pages access checks
  mm, pagevec: rename pagevec drained field
  ...

1 files changed, 13 insertions, 2 deletions

diff --git a/mm/ksm.c b/mm/ksm.c
index 6cb60f46cce5..be8f4576f842 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1052,8 +1052,13 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
 		 * So we clear the pte and flush the tlb before the check
 		 * this assure us that no O_DIRECT can happen after the check
 		 * or in the middle of the check.
+		 *
+		 * No need to notify as we are downgrading page table to read
+		 * only not changing it to point to a new page.
+		 *
+		 * See Documentation/vm/mmu_notifier.txt
 		 */
-		entry = ptep_clear_flush_notify(vma, pvmw.address, pvmw.pte);
+		entry = ptep_clear_flush(vma, pvmw.address, pvmw.pte);
 		/*
 		 * Check that no O_DIRECT or similar I/O is in progress on the
 		 * page
@@ -1136,7 +1141,13 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
 	}
 
 	flush_cache_page(vma, addr, pte_pfn(*ptep));
-	ptep_clear_flush_notify(vma, addr, ptep);
+	/*
+	 * No need to notify as we are replacing a read only page with another
+	 * read only page with the same content.
+	 *
+	 * See Documentation/vm/mmu_notifier.txt
+	 */
+	ptep_clear_flush(vma, addr, ptep);
 	set_pte_at_notify(mm, addr, ptep, newpte);
 
 	page_remove_rmap(page, false);