userfaultfd: use mmgrab instead of open-coded increment of mm_count

Link: http://lkml.kernel.org/r/1508132478-7738-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mike Rapoport 2017-11-15 17:36:56 -08:00 committed by Linus Torvalds
parent 85ccc8fa81
commit 00bb31fa44
1 changed files with 1 additions and 1 deletions

View File

@ -668,7 +668,7 @@ 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_count);
mmgrab(ctx->mm);
userfaultfd_ctx_get(octx);
fctx->orig = octx;