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Date: Mon, 16 May 2016 17:25:22 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>,
        Andrea Arcangeli <aarcange@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: [PATCH 0/1] userfaultfd: don't pin the user memory in
 userfaultfd_file_create()
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Hello,

Sorry for delay. So this is the same patch, just I added the helpers for get/put
mm->mm_users. I won't mind to change userfaultfd_get_mm() to return mm_struct-or-
NULL, or perhaps instead we should simply add the trivial helper which does
atomic_inc_not_zero(mm->mm_users) into sched.h, it can have more callers (fs/proc,
uprobes).

Testing. I have found selftests/vm/userfaultfd.c and it seems to work.

Oleg.