Re: [PATCH 5/6] mm/page_alloc.c: avoid accessing uninitialized pcp page migratetype

From: Mel Gorman
Date: Tue Aug 31 2021 - 09:43:23 EST


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@xxxxxxxxxx>

Acked-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>

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.


--
Mel Gorman
SUSE Labs