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Date:   Tue, 13 Apr 2021 12:16:30 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Mel Gorman <mgorman@techsingularity.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Oscar Salvador <osalvador@suse.de>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Alexander Duyck <alexanderduyck@fb.com>,
        Minchan Kim <minchan@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 resend] mm/memory_hotplug: Make unpopulated zones PCP
 structures unreachable during hot remove
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References: <20210412120842.GY3697@techsingularity.net>
 <d4e4c3e4-7d47-d634-4374-4cf1e55c7895@suse.cz>
 <20210412140852.GZ3697@techsingularity.net>
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On Tue 13-04-21 11:36:08, Vlastimil Babka wrote:
[...]
> AFAIK even Oscar's work on using the node to self-contain its own structures is
> only applicable to struct pages, not percpu allocations?

Correct. Teaching pcp storage on movable zone sounds like a large
undertaking to me. Not sure this is worth it TBH. Even an idea of any
pcp access synchronization with memory hotplug makes for a decent headache.

-- 
Michal Hocko
SUSE Labs