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Date:   Fri, 14 Oct 2022 15:40:10 +0200
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Subject: Re: RFC [PATCH v4 2/7] Enable balloon drivers to report inflated
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To:     Alexander Atanasov <alexander.atanasov@virtuozzo.com>,
        Nadav Amit <nadav.amit@gmail.com>
Cc:     "Michael S. Tsirkin" <mst@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>, kernel@openvz.org,
        Linux Virtualization <virtualization@lists.linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux MM <linux-mm@kvack.org>
References: <20221005090158.2801592-1-alexander.atanasov@virtuozzo.com>
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 <88EDC41D-408F-4ADF-A933-0A6F36E5F262@gmail.com>
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 <d55338c4-d15f-14ec-c057-806a5d5aa618@virtuozzo.com>
 <71E14334-CA3B-45FB-A854-7A8D6649C798@gmail.com>
 <b7dd38ba-9ff9-6b4c-2460-d4b1ee3bb3f0@virtuozzo.com>
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 <7ba328e5-3bc8-cb22-f00c-eddb8aea9a06@virtuozzo.com>
 <063efd58-8373-90ea-7c5e-9d0e9161d2ba@redhat.com>
 <04e5a2e4-052d-0f80-d642-4e104307f38b@virtuozzo.com>
 <72e535ce-80eb-a02f-970c-6a9c80da0a24@redhat.com>
 <5b1e0a13-8018-630d-d512-c3033db2f2e3@virtuozzo.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <5b1e0a13-8018-630d-d512-c3033db2f2e3@virtuozzo.com>
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>>>
>>> Other problem is that there are drivers that do not use
>>> adjust_managed_page_count().
>>
>> Which ones? Do we care?
> 
> VMWare and Virtio balloon drivers. I recently proposed to unify them and
> the objection was that it would break existing users - which is valid so
> we must care i guess.

I'm confused, I think we care about actual adjustment of the total pages 
available here, that we want to notify the system about. These 
approaches (vmware, virtio-balloon with deflate-on-oom) don't adjust 
totalpages, because the assumption is that we can get back the inflated 
memory any time we really need it automatically.

-- 
Thanks,

David / dhildenb