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Subject: Re: [PATCH v2 4/5] mm/hugeltb: handle the error case in
 hugetlb_fix_reserve_counts()
To:     Miaohe Lin <linmiaohe@huawei.com>, akpm@linux-foundation.org
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linfeilong@huawei.com
References: <20210410072348.20437-1-linmiaohe@huawei.com>
 <20210410072348.20437-5-linmiaohe@huawei.com>
From:   Mike Kravetz <mike.kravetz@oracle.com>
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Date:   Mon, 12 Apr 2021 11:30:06 -0700
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On 4/10/21 12:23 AM, Miaohe Lin wrote:
> A rare out of memory error would prevent removal of the reserve map region
> for a page. hugetlb_fix_reserve_counts() handles this rare case to avoid
> dangling with incorrect counts. Unfortunately, hugepage_subpool_get_pages
> and hugetlb_acct_memory could possibly fail too. We should correctly handle
> these cases.
> 
> Fixes: b5cec28d36f5 ("hugetlbfs: truncate_hugepages() takes a range of pages")
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>

Thanks,

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