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Date:   Wed, 6 Jan 2021 19:09:25 +0000 (UTC)
From:   Christoph Lameter <cl@linux.com>
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To:     Vlastimil Babka <vbabka@suse.cz>
cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Qian Cai <cai@redhat.com>,
        David Hildenbrand <david@redhat.com>,
        Michal Hocko <mhocko@kernel.org>
Subject: Re: [RFC 0/3] mm, slab, slub: remove cpu and memory hotplug locks
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On Wed, 6 Jan 2021, Vlastimil Babka wrote:

> rather accept some wasted memory in scenarios that should be rare anyway (full
> memory hot remove), as we do the same in other contexts already. It's all RFC
> for now, as I might have missed some reason why it's not safe.

Looks good to me. My only concern is the kernel that has hotplug disabled.
Current code allows the online/offline checks to be optimized away.

Can this patch be enhanced to do the same?