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From: Xishi Qiu <qiuxishi@huawei.com>
Newsgroups: linux.kernel
Subject: Re: [PATCH 1/3] mm: fix set pageblock migratetype in deferred struct  page init
Date: Tue, 16 Aug 2016 11:00:01 +0200
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On 2016/8/16 16:41, Michal Hocko wrote:

> On Thu 04-08-16 19:25:03, Xishi Qiu wrote:
>> MAX_ORDER_NR_PAGES is usually 4M, and a pageblock is usually 2M, so we only
>> set one pageblock's migratetype in deferred_free_range() if pfn is aligned
>> to MAX_ORDER_NR_PAGES.
> 
> Do I read the changelog correctly and the bug causes leaking unmovable
> allocations into movable zones?

Hi Michal,

This bug will cause uninitialized migratetype, you can see from
"cat /proc/pagetypeinfo", almost half blocks are Unmovable.

Also this bug missed to free the last block pages, it cause memory leaking.

Thanks,
Xishi Qiu