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Date: Tue, 12 Jan 2016 14:40:20 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: nimisolo <nimisolo@gmail.com>
Cc: kuleshovmail@gmail.com, penberg@kernel.org, tony.luck@intel.com,
        mgorman@suse.de, tangchen@cn.fujitsu.com, weiyang@linux.vnet.ibm.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/memblock: If nr_new is 0 just return
Message-Id: <20160112144020.db1cd77e97e41d5c48024c3c@linux-foundation.org>
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On Sat,  9 Jan 2016 06:33:40 -0500 nimisolo <nimisolo@gmail.com> wrote:

> If nr_new is 0 which means there's no region would be added,
> so just return to the caller.
> 
> ...
>
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -588,6 +588,9 @@ repeat:
>  					       nid, flags);
>  	}
>  
> +	if (!nr_new)
> +		return 0;
> +
>  	/*
>  	 * If this was the first round, resize array and repeat for actual
>  	 * insertions; otherwise, merge and return.

hm, why?  Is there something actually wrong with the current code?

Under what circumstances does nr_new==0 actually happen?  Is it a bug
in the caller?