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Date: Mon, 23 Apr 2018 00:58:56 -0400 (EDT)
From: Pankaj Gupta <pagupta@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v3 0/3] pc-dimm: factor out MemoryDevice
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To: David Hildenbrand <david@redhat.com>
Cc: qemu-devel@nongnu.org, Eduardo Habkost <ehabkost@redhat.com>, "Michael S . Tsirkin" <mst@redhat.com>, Markus Armbruster <armbru@redhat.com>, qemu-s390x@nongnu.org, qemu-ppc@nongnu.org, Paolo Bonzini <pbonzini@redhat.com>, Marcel Apfelbaum <marcel@redhat.com>, Igor Mammedov <imammedo@redhat.com>, David Gibson <david@gibson.dropbear.id.au>, Richard Henderson <rth@twiddle.net>


> > 
> > Hello,
> > 
> > This is good re-factoring and needed for 'virtio-pmem' as well to
> > reserve memory region in system address space.
> > 
> > I have tested this code with virtio-pmem and its working fine. Thank you
> > for the work.
> > 
> > I just have a small suggestion : when functions like(get_addr(),
> > get_plugged_size etc)
> > in the interface are not provided by derived class, Qemu crashes.
> > 
> > I think having a contract for must override functions with NULL check and
> > error
> > at the calling sites would be better?
> 
> I expect that all of these functions are implemented. It's a contract
> for devices that are mapped into address space. We might later have
> additional functions that might not be required to be provided and will
> be checked for NULL.
> 
> So for the current set of functions, I don't think it makes sense to
> make them optional.

o.k. that's reasonable.

Thanks,
Pankaj
> 
> Thanks!
> 
> > 
> > Thanks,
> > Pankaj
> 
> 
> --
> 
> Thanks,
> 
> David / dhildenb
>