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Message-ID: <a99f0684-b075-7fc5-082a-2c0cc706574b@redhat.com>
Date:   Mon, 26 Sep 2022 10:05:05 +0200
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Subject: Re: [PATCH v5 4/4] mm/hwpoison: introduce per-memory_block hwpoison
 counter counter
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To:     Naoya Horiguchi <naoya.horiguchi@linux.dev>, linux-mm@kvack.org
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Yang Shi <shy828301@gmail.com>,
        Oscar Salvador <osalvador@suse.de>,
        Muchun Song <songmuchun@bytedance.com>,
        Jane Chu <jane.chu@oracle.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        linux-kernel@vger.kernel.org
References: <20220921091359.25889-1-naoya.horiguchi@linux.dev>
 <20220921091359.25889-5-naoya.horiguchi@linux.dev>
 <20220923082613.GB1357512@ik1-406-35019.vs.sakura.ne.jp>
 <20220923141204.GA1484969@ik1-406-35019.vs.sakura.ne.jp>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20220923141204.GA1484969@ik1-406-35019.vs.sakura.ne.jp>
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>   /*
> @@ -2414,6 +2417,10 @@ int unpoison_memory(unsigned long pfn)
>   unlock_mutex:
>   	mutex_unlock(&mf_mutex);
>   	if (!ret || freeit) {
> +		/*
> +		 * TODO: per-memory_block counter might break when the page
> +		 * size to be unpoisoned is larger than a memory_block.
> +		 */

Hmm, but that happens easily e.g., with 1 GiB hugetlb page and 128 MiB 
memory section/block size. What would be the right thing to do here? The 
TODO should rather spell that out instead of just stating the problem.

-- 
Thanks,

David / dhildenb