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Date:   Thu, 14 Jul 2022 11:45:29 -0400
From:   Peter Xu <peterx@redhat.com>
To:     Miaohe Lin <linmiaohe@huawei.com>
Cc:     Axel Rasmussen <axelrasmussen@google.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Muchun Song <songmuchun@bytedance.com>,
        Linux MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm/hugetlb: avoid corrupting page->mapping in
 hugetlb_mcopy_atomic_pte
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On Thu, Jul 14, 2022 at 06:09:49PM +0800, Miaohe Lin wrote:
> As discussed in another thread, we might call page_dup_file_rmap for newly
> allocated page (regardless of this patch). So should we come up a seperate
> patch to call page_add_file_rmap here instead?

Hmm, why we need page_add_file_rmap() even if a new page allocated?  Say,
we're at least also using page_dup_file_rmap() in hugetlb_no_page().

I see majorly two things extra there: memcg accounts on NR_FILE_MAPPED, and
mlock.  But I assume both of them will not apply to hugetlb pages?

-- 
Peter Xu