userfaultfd: non-cooperative: dup_userfaultfd: use mm_count instead of mm_users

Since commit d2005e3f41d4 ("userfaultfd: don't pin the user memory in
userfaultfd_file_create()") userfaultfd uses mm_count rather than
mm_users to pin mm_struct.

Make dup_userfaultfd consistent with this behaviour

Link: http://lkml.kernel.org/r/20161216144821.5183-11-aarcange@redhat.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 6046e0b552b2..27978f249016 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -558,7 +558,7 @@ int dup_userfaultfd(struct vm_area_struct *vma, struct list_head *fcs)
                 ctx->features = octx->features;
                 ctx->released = false;
                 ctx->mm = vma->vm_mm;
-                atomic_inc(&ctx->mm->mm_users);
+                atomic_inc(&ctx->mm->mm_count);
 
                 userfaultfd_ctx_get(octx);
                 fctx->orig = octx;