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Date: Fri, 19 Oct 2018 08:28:01 +0000
From: Wei Yang <richard.weiyang@gmail.com>
Subject: Re: [PATCH] mm/sparse: remove a check that compare if unsigned
 variable is negative
Message-ID: <20181019082801.kbnqxx5ozghy3p3b@master>
Reply-To: Wei Yang <richard.weiyang@gmail.com>
References: <1539447319-5383-1-git-send-email-penghao122@sina.com.cn>
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To: Pavel Tatashin <pasha.tatashin@gmail.com>
Cc: penghao122@sina.com.cn, Linux Memory Management List <linux-mm@kvack.org>, Andrew Morton <akpm@linux-foundation.org>, pasha.tatashin@oracle.com, osalvador@suse.de, LKML <linux-kernel@vger.kernel.org>, peng.hao2@zte.com.cn

On Sat, Oct 13, 2018 at 01:04:45PM -0400, Pavel Tatashin wrote:
>This is incorrect: next_present_section_nr() returns "int" and -1 no
>next section, this change would lead to infinite loop.

Yes, the -1 is a very special value.

-- 
Wei Yang
Help you, Help me