Merge branch 'akpm' (patches from Andrew)

Merge misc patches from Andrew Morton:
 "A few stragglers"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  tools/testing/selftests/Makefile: alphasort the TARGETS list
  mm/zsmalloc: adjust order of functions
  ocfs2: fix journal commit deadlock
  ocfs2/dlm: fix race between dispatched_work and dlm_lockres_grab_inflight_worker
  ocfs2: reflink: fix slow unlink for refcounted file
  mm/memory.c:do_shared_fault(): add comment
  .mailmap: Santosh Shilimkar has moved
  .mailmap: update akpm@osdl.org
  lib/show_mem.c: add cma reserved information
  fs/proc/meminfo.c: include cma info in proc/meminfo
  mm: cma: split cma-reserved in dmesg log
  hfsplus: fix longname handling
  mm/mempolicy.c: remove unnecessary is_valid_nodemask()

1 files changed, 6 insertions, 0 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 6efe36a998ba..d8aebc52265f 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2996,6 +2996,12 @@ static int do_shared_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 
         if (set_page_dirty(fault_page))
                 dirtied = 1;
+        /*
+         * Take a local copy of the address_space - page.mapping may be zeroed
+         * by truncate after unlock_page().   The address_space itself remains
+         * pinned by vma->vm_file's reference.  We rely on unlock_page()'s
+         * release semantics to prevent the compiler from undoing this copying.
+         */
         mapping = fault_page->mapping;
         unlock_page(fault_page);
         if ((dirtied || vma->vm_ops->page_mkwrite) && mapping) {