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Date:   Wed, 30 Nov 2022 11:15:56 +0100
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Subject: Re: [PATCH 02/10] mm/hugetlb: Don't wait for migration entry during
 follow page
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To:     Peter Xu <peterx@redhat.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Cc:     James Houghton <jthoughton@google.com>,
        Jann Horn <jannh@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Rik van Riel <riel@surriel.com>,
        Nadav Amit <nadav.amit@gmail.com>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Mike Kravetz <mike.kravetz@oracle.com>
References: <20221129193526.3588187-1-peterx@redhat.com>
 <20221129193526.3588187-3-peterx@redhat.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20221129193526.3588187-3-peterx@redhat.com>
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On 29.11.22 20:35, Peter Xu wrote:
> That's what the code does with !hugetlb pages, so we should logically do
> the same for hugetlb, so migration entry will also be treated as no page.
> 
> This is probably also the last piece in follow_page code that may sleep,
> the last one should be removed in cf994dd8af27 ("mm/gup: remove
> FOLL_MIGRATION", 2022-11-16).

We only have a handful of follow_page() calls left. Most relevant for 
hugetlb should only be the ones from mm/migrate.c.

So this is now just consistent with ordinary pages/THP.

Happy so see that gone.

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Thanks,

David / dhildenb