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Date:   Tue, 31 Aug 2021 18:34:26 +0200
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Subject: Re: [PATCH 5/6] mm/page_alloc.c: avoid accessing uninitialized pcp
 page migratetype
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To:     Mel Gorman <mgorman@techsingularity.net>,
        Miaohe Lin <linmiaohe@huawei.com>
Cc:     akpm@linux-foundation.org, sfr@canb.auug.org.au,
        peterz@infradead.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
References: <20210830141051.64090-1-linmiaohe@huawei.com>
 <20210830141051.64090-6-linmiaohe@huawei.com>
 <20210831134311.GG4128@techsingularity.net>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20210831134311.GG4128@techsingularity.net>
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On 8/31/21 15:43, Mel Gorman wrote:
> On Mon, Aug 30, 2021 at 10:10:50PM +0800, Miaohe Lin wrote:
>> If it's not prepared to free unref page, the pcp page migratetype is
>> unset. Thus We will get rubbish from get_pcppage_migratetype() and
>> might list_del &page->lru again after it's already deleted from the
>> list leading to grumble about data corruption.
>> 
>> Fixes: 3dcbe270d8ec ("mm/page_alloc: avoid conflating IRQs disabled with zone->lock")
>> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> 
> Acked-by: Mel Gorman <mgorman@techsingularity.net>
> 
> This fix is fairly important. Take this patch out and send it on its own
> so it gets picked up relatively quickly. It does not belong in a series
> that is mostly cosmetic cleanups.

Also Cc: stable, please.