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Date:   Wed, 14 Sep 2022 13:49:27 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Doug Berger <opendmb@gmail.com>
Cc:     Mike Kravetz <mike.kravetz@oracle.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Oscar Salvador <osalvador@suse.de>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] mm/hugetlb: correct demote page offset logic
Message-Id: <20220914134927.16c229ccdc1a6b9da5d698c3@linux-foundation.org>
In-Reply-To: <20220914190917.3517663-1-opendmb@gmail.com>
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On Wed, 14 Sep 2022 12:09:17 -0700 Doug Berger <opendmb@gmail.com> wrote:

> With gigantic pages it may not be true that struct page structures
> are contiguous across the entire gigantic page. The nth_page macro
> is used here in place of direct pointer arithmetic to correct for
> this.

What were the user-visible runtime effects of this bug?