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Date:   Thu, 23 Mar 2023 15:18:50 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Muchun Song <songmuchun@bytedance.com>
Cc:     glider@google.com, elver@google.com, dvyukov@google.com,
        jannh@google.com, sjpark@amazon.de, muchun.song@linux.dev,
        kasan-dev@googlegroups.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: kfence: fix handling discontiguous page
Message-Id: <20230323151850.e2785b1cff37fba078f26f2b@linux-foundation.org>
In-Reply-To: <20230323025003.94447-1-songmuchun@bytedance.com>
References: <20230323025003.94447-1-songmuchun@bytedance.com>
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On Thu, 23 Mar 2023 10:50:03 +0800 Muchun Song <songmuchun@bytedance.com> wrote:

> The struct pages could be discontiguous when the kfence pool is allocated
> via alloc_contig_pages() with CONFIG_SPARSEMEM and !CONFIG_SPARSEMEM_VMEMMAP.
> So, the iteration should use nth_page().

What are the user-visible runtime effects of this flaw?

Thanks.