From mboxrd@z Thu Jan  1 00:00:00 1970
From: Barret Rhoden <brho-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCH V5 4/4] kvm: add a check if pfn is from NVDIMM pmem.
Date: Fri, 19 Oct 2018 12:33:48 -0400
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Cc: KVM list <kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, "Zhang, Yu C" <yu.c.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
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 rkrcmar-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Linux Kernel Mailing List <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
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 Paolo Bonzini <pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Christoph Hellwig <hch-jcswGhMUV9g@public.gmane.org>, "Zhang,
 Yi Z" <yi.z.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
To: David Hildenbrand <david-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Dan Williams
 <dan.j.williams-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
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On 2018-09-21 at 21:29 David Hildenbrand <david-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> On 21/09/2018 20:17, Dan Williams wrote:
> > On Fri, Sep 21, 2018 at 7:24 AM David Hildenbrand <david-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 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().
> >   
> 
> Indeed, that sounds like the easiest solution - guess that answer was
> too easy for me to figure out :) .
> 

Just to follow-up, is the plan to clear PageReserved for nvdimm pages
instead of the approach taken in this patch set?  Or should we special
case nvdimm/dax pages in kvm_is_reserved_pfn()?

Thanks,

Barret