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Subject: Re: [PATCH 15/23] hugetlb/userfaultfd: Hook page faults for uffd
 write protection
To:     Peter Xu <peterx@redhat.com>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Cc:     "Kirill A . Shutemov" <kirill@shutemov.name>,
        Jerome Glisse <jglisse@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Hugh Dickins <hughd@google.com>,
        Nadav Amit <nadav.amit@gmail.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Mike Rapoport <rppt@linux.vnet.ibm.com>
References: <20210323004912.35132-1-peterx@redhat.com>
 <20210323004912.35132-16-peterx@redhat.com>
From:   Mike Kravetz <mike.kravetz@oracle.com>
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On 3/22/21 5:49 PM, Peter Xu wrote:
> Hook up hugetlbfs_fault() with the capability to handle userfaultfd-wp faults.
> 
> We do this slightly earlier than hugetlb_cow() so that we can avoid taking some
> extra locks that we definitely don't need.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  mm/hugetlb.c | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)

That is pretty straight forward,

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
-- 
Mike Kravetz