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From:   Dan Williams <dan.j.williams@intel.com>
Date:   Fri, 21 Sep 2018 11:17:13 -0700
Message-ID: <CAPcyv4j9K-wkq8oK-8_twWViKhyGSHD7cOE5UoRN-09xKXPq7A@mail.gmail.com>
Subject: Re: [PATCH V5 4/4] kvm: add a check if pfn is from NVDIMM pmem.
To:     David Hildenbrand <david@redhat.com>
Cc:     KVM list <kvm@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-nvdimm <linux-nvdimm@lists.01.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Dave Jiang <dave.jiang@intel.com>,
        "Zhang, Yu C" <yu.c.zhang@intel.com>,
        Pankaj Gupta <pagupta@redhat.com>, Jan Kara <jack@suse.cz>,
        Christoph Hellwig <hch@lst.de>, Linux MM <linux-mm@kvack.org>,
        rkrcmar@redhat.com,
        =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= <jglisse@redhat.com>,
        "Zhang, Yi Z" <yi.z.zhang@intel.com>
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On Fri, Sep 21, 2018 at 7:24 AM David Hildenbrand <david@redhat.com> wrote:
[..]
> > Remove the PageReserved flag sounds more reasonable.
> > And Could we still have a flag to identify it is a device private memory, or
> > where these pages coming from?
>
> We could use a page type for that or what you proposed. (as I said, we
> might have to change hibernation code to skip the pages once we drop the
> reserved flag).

I think it would be reasonable to reject all ZONE_DEVICE pages in
saveable_page().