From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37681) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZAbB8-0005NZ-Cq for qemu-devel@nongnu.org; Thu, 02 Jul 2015 05:53:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZAbB3-0001EU-61 for qemu-devel@nongnu.org; Thu, 02 Jul 2015 05:53:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41166) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZAbB3-0001EO-0x for qemu-devel@nongnu.org; Thu, 02 Jul 2015 05:53:05 -0400 References: <1435762232-15543-1-git-send-email-guangrong.xiao@linux.intel.com> <20150702092044.GB20198@stefanha-thinkpad.redhat.com> From: Paolo Bonzini Message-ID: <559509FA.20509@redhat.com> Date: Thu, 2 Jul 2015 11:52:58 +0200 MIME-Version: 1.0 In-Reply-To: <20150702092044.GB20198@stefanha-thinkpad.redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 00/16] implement vNVDIMM List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi , Xiao Guangrong Cc: ehabkost@redhat.com, kvm@vger.kernel.org, mst@redhat.com, gleb@kernel.org, mtosatti@redhat.com, qemu-devel@nongnu.org, =?UTF-8?Q?Marc-Andr=c3=a9_Lureau?= , stefanha@redhat.com, imammedo@redhat.com, rth@twiddle.net On 02/07/2015 11:20, Stefan Hajnoczi wrote: > > Currently, the NVDIMM driver has been merged into upstream Linux Kern= el and > > this patchset tries to enable it in virtualization field >=20 > From a device model perspective, have you checked whether it makes sens= e > to integrate nvdimms into the pc-dimm and hostmem code that is used for > memory hotplug and NUMA? >=20 > The NVDIMM device in your patches is a completely new TYPE_DEVICE so it > doesn't share any interfaces or code with existing memory devices. > Maybe that is the right solution here because NVDIMMs have different > characteristics, but I'm not sure. The hostmem code should definitely be shared, e.g. by adding a new "file" property to the memory-backend-file class. ivshmem can also use it---CCing Marc-Andr=E9. I don't know about the pc-dimm devices. If the NVDIMM devices can do _OST and can be hotplugged, then the answer is probably yes. Paolo