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Date:   Tue, 27 Sep 2022 14:26:19 -0700
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Subject: Re: [RFC PATCH v2 9/9] mm: Introduce Copy-On-Write PTE table
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To:     Chih-En Lin <shiyn.lin@gmail.com>, Nadav Amit <namit@vmware.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Qi Zheng <zhengqi.arch@bytedance.com>,
        David Hildenbrand <david@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-mm@kvack.org" <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>,
        Peter Xu <peterx@redhat.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Tong Tiangen <tongtiangen@huawei.com>,
        Pasha Tatashin <pasha.tatashin@soleen.com>,
        Li kunyu <kunyu@nfschina.com>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Minchan Kim <minchan@kernel.org>,
        Yang Shi <shy828301@gmail.com>, Song Liu <song@kernel.org>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Dinglan Peng <peng301@purdue.edu>,
        Pedro Fonseca <pfonseca@purdue.edu>,
        Jim Huang <jserv@ccns.ncku.edu.tw>,
        Huichun Feng <foxhoundsk.tw@gmail.com>
References: <20220927162957.270460-1-shiyn.lin@gmail.com>
 <20220927162957.270460-10-shiyn.lin@gmail.com>
 <3D21021E-490F-4FE0-9C75-BB3A46A66A26@vmware.com>
 <YzNUwxU44mq+KnCm@strix-laptop>
From:   John Hubbard <jhubbard@nvidia.com>
In-Reply-To: <YzNUwxU44mq+KnCm@strix-laptop>
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On 9/27/22 12:53, Chih-En Lin wrote:
> I'm not familiar with THP right now. But we have a plan for looking
> at it to see what will happen with COW PTE.
> Currently, I can only say that I prefer to avoid involving the behavior
> of huge-page/THP. If there are any ideas here please tell us.
> 
In order to be considered at all, this would have to at least behave 
correctly in the presence of THP and hugetlbfs, IMHO. Those are no
longer niche features.


thanks,

-- 
John Hubbard
NVIDIA