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Subject: Re: [PATCH] mm/sparse: Add the missing sparse_buffer_fini() in error
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To:     Wang Wensheng <wangwensheng4@huawei.com>,
        akpm@linux-foundation.org, osalvador@suse.de,
        pasha.tatashin@oracle.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Cc:     rui.xiang@huawei.com
References: <20210325113155.118574-1-wangwensheng4@huawei.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat GmbH
Message-ID: <1f20f644-9f51-5f0b-a162-c340912b5212@redhat.com>
Date:   Thu, 25 Mar 2021 13:45:13 +0100
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On 25.03.21 12:31, Wang Wensheng wrote:
> sparse_buffer_init() and sparse_buffer_fini() should appear in pair, or
> a WARN issue would be through the next time sparse_buffer_init() runs.
> 
> Add the missing sparse_buffer_fini() in error branch.
> 
> Fixes: 85c77f791390 ("mm/sparse: add new sparse_init_nid() and sparse_init()")
> Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
> ---
>   mm/sparse.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/mm/sparse.c b/mm/sparse.c
> index 7bd23f9..33406ea 100644
> --- a/mm/sparse.c
> +++ b/mm/sparse.c
> @@ -547,6 +547,7 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
>   			pr_err("%s: node[%d] memory map backing failed. Some memory will not be available.",
>   			       __func__, nid);
>   			pnum_begin = pnum;
> +			sparse_buffer_fini();
>   			goto failed;
>   		}
>   		check_usemap_section_nr(nid, usage);
> 

Did you actually manage to reproduce this? I would have thought that 
__populate_section_memmap() barely fails during boot ...


Anyhow, looks like the right think to do to me

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Thanks,

David / dhildenb