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Date:   Wed, 28 Sep 2022 03:07:13 +0800
From:   Chih-En Lin <shiyn.lin@gmail.com>
To:     Nadav Amit <namit@vmware.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Qi Zheng <zhengqi.arch@bytedance.com>,
        David Hildenbrand <david@redhat.com>,
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        Linux MM <linux-mm@kvack.org>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Iurii Zaikin <yzaikin@google.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        William Kucharski <william.kucharski@oracle.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
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        Suren Baghdasaryan <surenb@google.com>,
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        Yang Shi <shy828301@gmail.com>, Song Liu <song@kernel.org>,
        Miaohe Lin <linmiaohe@huawei.com>,
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        Jim Huang <jserv@ccns.ncku.edu.tw>,
        Huichun Feng <foxhoundsk.tw@gmail.com>
Subject: Re: [RFC PATCH v2 5/9] mm, pgtable: Add a refcount to PTE table
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On Tue, Sep 27, 2022 at 05:59:16PM +0000, Nadav Amit wrote:
> Is there some assumption that pmd_get_pte() would not be called between the
> page_ref_add_unless() and cow_pte_fallback()?
> 
> Hard to know without comments or context.

Yes.
It is one of the corner case that I need to handle it.

Thanks,
Chih-En Lin