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Date:   Wed, 26 May 2021 12:43:15 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     David Hildenbrand <david@redhat.com>
Cc:     Ding Hui <dinghui@sangfor.com.cn>, akpm@linux-foundation.org,
        naoya.horiguchi@nec.com, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH v3] mm/page_alloc: fix counting of free pages after take
 off from buddy
Message-ID: <20210526104315.GD1656@linux>
References: <20210526075247.11130-1-dinghui@sangfor.com.cn>
 <301ec664-f153-7ed6-0231-8bbffb630a0d@redhat.com>
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On Wed, May 26, 2021 at 09:58:15AM +0200, David Hildenbrand wrote:
> I guess if we'd actually be removing a page from the buddy while it's
> currently isolated by someone else (i.e., alloc_contig_range()), we might be
> in bigger trouble.
> 
> I think we should actually skip isolated pages completely.
> take_page_off_buddy() should not touch them.

That might be a problem indeed.
I will have a look at it.

Thanks

-- 
Oscar Salvador
SUSE L3