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Subject: Re: [PATCH v8 3/7] mm,hugetlb: Drop clearing of flag from
 prep_new_huge_page
To:     Oscar Salvador <osalvador@suse.de>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     Vlastimil Babka <vbabka@suse.cz>,
        David Hildenbrand <david@redhat.com>,
        Michal Hocko <mhocko@kernel.org>,
        Muchun Song <songmuchun@bytedance.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
References: <20210415103544.6791-1-osalvador@suse.de>
 <20210415103544.6791-4-osalvador@suse.de>
From:   Mike Kravetz <mike.kravetz@oracle.com>
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Date:   Thu, 15 Apr 2021 11:50:19 -0700
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On 4/15/21 3:35 AM, Oscar Salvador wrote:
> Pages allocated after boot get its private field cleared by means
> of post_alloc_hook().
> Pages allocated during boot, that is directly from the memblock allocator,
> get cleared by paging_init()->..->memmap_init_zone->..->__init_single_page()
> before any memblock allocation.
> 
> Based on this ground, let us remove the clearing of the flag from
> prep_new_huge_page() as it is not needed.
> 
> Signed-off-by: Oscar Salvador <osalvador@suse.de>

The comment "allocated after boot" made sense to me, but I can see where
Michal's suggestion was coming from (list the allocators that do the
clearing).

Also, listing this as a left over would be a good idea.

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
-- 
Mike Kravetz