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Subject: Re: mmotm 2020-07-27-18-18 uploaded (mm/page_alloc.c)
To:     "Michael S. Tsirkin" <mst@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     Stephen Rothwell <sfr@canb.auug.org.au>,
        Randy Dunlap <rdunlap@infradead.org>, broonie@kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, linux-next@vger.kernel.org, mhocko@suse.cz,
        mm-commits@vger.kernel.org, Jason Wang <jasowang@redhat.com>
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From:   David Hildenbrand <david@redhat.com>
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Date:   Wed, 29 Jul 2020 16:38:21 +0200
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On 29.07.20 16:18, Michael S. Tsirkin wrote:
> On Tue, Jul 28, 2020 at 03:31:43PM -0700, Andrew Morton wrote:
>> On Wed, 29 Jul 2020 08:20:53 +1000 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>>
>>> Hi Andrew,
>>>
>>> On Tue, 28 Jul 2020 14:55:53 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:
>>>> config CONTIG_ALLOC
>>>>         def_bool (MEMORY_ISOLATION && COMPACTION) || CMA
>>>>
>>>> says this is an improper combination.  And `make oldconfig' fixes it up.
>>>>
>>>> What's happening here?
>>>
>>> CONFIG_VIRTIO_MEM selects CONFIG_CONTIG_ALLOC ...
>>
>> Argh, select strikes again.
>>
>> So I guess VIRTIO_MEM should also select COMPACTION?
> 
> +Cc the maintainer.
> 

We had select CONFIG_CONTIG_ALLOC before and that seemed to be wrong. I
was told select might be the wrong approach.

We want memory isolation and contig_alloc with virtio-mem (which depends
on memory hot(un)plug). What would be the right way to achieve this?

-- 
Thanks,

David / dhildenb