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From:   Liang Li <liliang324@gmail.com>
Date:   Tue, 22 Dec 2020 20:13:12 +0800
Message-ID: <CA+2MQi8kupPHetMhH97fn+toFk9HUYeVPnwdzrpyiS6Necn0CA@mail.gmail.com>
Subject: Re: [RFC PATCH 3/3] mm: support free hugepage pre zero out
To:     David Hildenbrand <david@redhat.com>
Cc:     Alexander Duyck <alexander.h.duyck@linux.intel.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Dan Williams <dan.j.williams@intel.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Michal Hocko <mhocko@suse.com>,
        Liang Li <liliangleo@didiglobal.com>,
        Mike Kravetz <mike.kravetz@oracle.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, qemu-devel@nongnu.org
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> > Free page reporting in virtio-balloon doesn't give you any guarantees
> > regarding zeroing of pages. Take a look at the QEMU implementation -
> > e.g., with vfio all reports are simply ignored.
> >
> > Also, I am not sure if mangling such details ("zeroing of pages") into
> > the page reporting infrastructure is a good idea.
> >
>
> Oh, now I get what you are doing here, you rely on zero_free_pages of
> your other patch series and are not relying on virtio-balloon free page
> reporting to do the zeroing.
>
> You really should have mentioned that this patch series relies on the
> other one and in which way.

I am sorry for that. After I sent out the patch, I realized I should
mention that, so I sent out an updated version which added the
information you mentioned :)

Thanks !
Liang