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Date:   Fri, 24 Nov 2023 09:53:01 +0100
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Subject: Re: [PATCH v2 01/14] mm: Batch-copy PTE ranges during fork()
To:     Ryan Roberts <ryan.roberts@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Ard Biesheuvel <ardb@kernel.org>,
        Marc Zyngier <maz@kernel.org>,
        Oliver Upton <oliver.upton@linux.dev>,
        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Zenghui Yu <yuzenghui@huawei.com>,
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        Dmitry Vyukov <dvyukov@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Matthew Wilcox <willy@infradead.org>,
        Yu Zhao <yuzhao@google.com>,
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        Kefeng Wang <wangkefeng.wang@huawei.com>,
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Cc:     linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org,
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From:   David Hildenbrand <david@redhat.com>
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>> One could simply skip batching for now on pte_protnone() and focus on the
>> "writable" vs. "not-writable".
> 
> I'm not sure we can simply "skip" batching on pte_protnone() since we will need
> to terminate the batch if we spot it. But if we have to look for it anyway, we
> might as well just terminate the batch when the value of pte_protnone()
> *changes*. I'm also proposing to take this approach for pte_uffd_wp() which also
> needs to be carefully preserved per-pte.

Yes, that's what I meant.

-- 
Cheers,

David / dhildenb