From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 11FD9C5B578 for ; Mon, 1 Jul 2019 03:54:13 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D3216208CA for ; Mon, 1 Jul 2019 03:54:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D3216208CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:47528 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hhnON-0005dF-O4 for qemu-devel@archiver.kernel.org; Sun, 30 Jun 2019 23:54:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51829) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hhnNr-000587-Pc for qemu-devel@nongnu.org; Sun, 30 Jun 2019 23:53:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hhnNq-0007JG-D1 for qemu-devel@nongnu.org; Sun, 30 Jun 2019 23:53:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34868) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hhnNq-000772-44 for qemu-devel@nongnu.org; Sun, 30 Jun 2019 23:53:38 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F2DFA308339E; Mon, 1 Jul 2019 03:53:06 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0C7157A4A7; Mon, 1 Jul 2019 03:53:06 +0000 (UTC) Received: from zmail21.collab.prod.int.phx2.redhat.com (zmail21.collab.prod.int.phx2.redhat.com [10.5.83.24]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id E6771206D1; Mon, 1 Jul 2019 03:53:04 +0000 (UTC) Date: Sun, 30 Jun 2019 23:53:03 -0400 (EDT) From: Pankaj Gupta To: qemu-devel@nongnu.org Message-ID: <678909315.38216446.1561953183580.JavaMail.zimbra@redhat.com> In-Reply-To: <20190619094907.10131-1-pagupta@redhat.com> References: <20190619094907.10131-1-pagupta@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.116.128, 10.4.195.19] Thread-Topic: Qemu virtio pmem device Thread-Index: 2xx2Y+youX9y9dYx9hligXxaIAYzfw== X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.44]); Mon, 01 Jul 2019 03:53:07 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v2 0/7] Qemu virtio pmem device X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, aarcange@redhat.com, xiaoguangrong eric , riel@surriel.com, rth@twiddle.net, cohuck@redhat.com, david@redhat.com, armbru@redhat.com, lcapitulino@redhat.com, mst@redhat.com, stefanha@redhat.com, imammedo@redhat.com, pbonzini@redhat.com, dan j williams , nilal@redhat.com, dgilbert@redhat.com, ehabkost@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Ping. > > This patch series has implementation for "virtio pmem" > device. "virtio pmem" is persistent memory(nvdimm) device in > guest which allows to bypass the guest page cache. This > also implements a VIRTIO based asynchronous flush mechanism. > Details of project idea for 'virtio pmem' flushing interface > is shared [2] & [3]. > > Sharing Qemu device emulation in this patchset. Tested with > guest kernel driver [1]. This series is based on David's > memory device refactoring [5] work with modified version of > my initial virtio pmem [4] series. > > Usage: > ./qemu -name test -machine pc -m 8G,slots=240,maxmem=20G > -object memory-backend-file,id=mem1,share,mem-path=test.img, > size=4G,share > -device virtio-pmem-pci,memdev=mem1,id=nv1 > > (qemu) info memory-devices > Memory device [virtio-pmem]: "nv1" > memaddr: 0x240000000 > size: 4294967296 > memdev: /objects/mem1 > > Implementation is divided into two parts: > New virtio pmem guest driver and qemu code changes for new > virtio pmem paravirtualized device. In this series we are > sharing Qemu device emulation. > > 1. Guest virtio-pmem kernel driver > --------------------------------- > - Reads persistent memory range from paravirt device and > registers with 'nvdimm_bus'. > - 'nvdimm/pmem' driver uses this information to allocate > persistent memory region and setup filesystem operations > to the allocated memory. > - virtio pmem driver implements asynchronous flushing > interface to flush from guest to host. > > 2. Qemu virtio-pmem device > --------------------------------- > - Creates virtio pmem device and exposes a memory range to > KVM guest. > - At host side this is file backed memory which acts as > persistent memory. > - Qemu side flush uses aio thread pool API's and virtio > for asynchronous guest multi request handling. > > Virtio-pmem security implications and suggested countermeasures: > --------------------------------------------------------------- > > In previous posting of kernel driver, there was discussion [7] > on possible implications of page cache side channel attacks with > virtio pmem. After thorough analysis of details of known side > channel attacks, below are the suggestions: > > - Depends entirely on how host backing image file is mapped > into guest address space. > > - virtio-pmem device emulation, by default shared mapping is used > to map host backing file. It is recommended to use separate > backing file at host side for every guest. This will prevent > any possibility of executing common code from multiple guests > and any chance of inferring guest local data based based on > execution time. > > - If backing file is required to be shared among multiple guests > it is recommended to don't support host page cache eviction > commands from the guest driver. This will avoid any possibility > of inferring guest local data or host data from another guest. > > - Proposed device specification [6] for virtio-pmem device with > details of possible security implications and suggested > countermeasures for device emulation. > > Changes from PATCH v1: > - Change proposed version from qemu 4.0 to 4.1 - Eric > - Remove virtio queue_add from unrealize function - Cornelia > > [1] https://lkml.org/lkml/2019/6/12/624 > [2] https://www.spinics.net/lists/kvm/msg149761.html > [3] https://www.spinics.net/lists/kvm/msg153095.html > [4] https://marc.info/?l=linux-kernel&m=153572228719237&w=2 > [5] https://marc.info/?l=qemu-devel&m=153555721901824&w=2 > [6] https://lists.oasis-open.org/archives/virtio-dev/201903/msg00083.html > [7] https://lkml.org/lkml/2019/1/9/1191 > > Pankaj Gupta (3): > virtio-pmem: add virtio device > virtio-pmem: sync linux headers > virtio-pci: proxy for virtio-pmem > > David Hildenbrand (4): > virtio-pci: Allow to specify additional interfaces for the base type > hmp: Handle virtio-pmem when printing memory device infos > numa: Handle virtio-pmem in NUMA stats > pc: Support for virtio-pmem-pci > > hmp.c | 27 ++- > hw/i386/Kconfig | 1 > hw/i386/pc.c | 72 ++++++++++ > hw/virtio/Kconfig | 10 + > hw/virtio/Makefile.objs | 2 > hw/virtio/virtio-pci.c | 1 > hw/virtio/virtio-pci.h | 1 > hw/virtio/virtio-pmem-pci.c | 131 ++++++++++++++++++ > hw/virtio/virtio-pmem-pci.h | 34 ++++ > hw/virtio/virtio-pmem.c | 189 > +++++++++++++++++++++++++++ > include/hw/pci/pci.h | 1 > include/hw/virtio/virtio-pmem.h | 49 +++++++ > include/standard-headers/linux/virtio_ids.h | 1 > include/standard-headers/linux/virtio_pmem.h | 35 +++++ > numa.c | 24 +-- > qapi/misc.json | 28 +++- > 16 files changed, 580 insertions(+), 26 deletions(-) > ---- > >