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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 B6646C3A5A5 for ; Thu, 5 Sep 2019 10:11:21 +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 842C021743 for ; Thu, 5 Sep 2019 10:11:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 842C021743 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]:44034 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i5ojY-0007D7-MX for qemu-devel@archiver.kernel.org; Thu, 05 Sep 2019 06:11:20 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53500) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i5ois-0006mF-8N for qemu-devel@nongnu.org; Thu, 05 Sep 2019 06:10:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i5oip-0001SQ-VC for qemu-devel@nongnu.org; Thu, 05 Sep 2019 06:10:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60196) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i5oip-0001Rg-PM for qemu-devel@nongnu.org; Thu, 05 Sep 2019 06:10:35 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7267A46673; Thu, 5 Sep 2019 10:10:34 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-117-72.ams2.redhat.com [10.36.117.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id DF55260CDA; Thu, 5 Sep 2019 10:10:07 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id 17F7F784F; Thu, 5 Sep 2019 12:10:07 +0200 (CEST) Date: Thu, 5 Sep 2019 12:10:07 +0200 From: Gerd Hoffmann To: Jagannathan Raman Message-ID: <20190905101007.s4elgn3jjjhypcmf@sirius.home.kraxel.org> References: <59cb496983f03b05f6da87af73bc2a2ac0bb7f81.1567534653.git.jag.raman@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <59cb496983f03b05f6da87af73bc2a2ac0bb7f81.1567534653.git.jag.raman@oracle.com> User-Agent: NeoMutt/20180716 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 05 Sep 2019 10:10:34 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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] [RFC v3 PATCH 44/45] multi-process: add the concept description to docs/devel/qemu-multiprocess 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: elena.ufimtseva@oracle.com, fam@euphon.net, john.g.johnson@oracle.com, mst@redhat.com, qemu-devel@nongnu.org, quintela@redhat.com, armbru@redhat.com, kanth.ghatraju@oracle.com, thuth@redhat.com, ehabkost@redhat.com, konrad.wilk@oracle.com, dgilbert@redhat.com, liran.alon@oracle.com, stefanha@redhat.com, rth@twiddle.net, kwolf@redhat.com, berrange@redhat.com, mreitz@redhat.com, ross.lagerwall@citrix.com, marcandre.lureau@gmail.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi, > +Current separation models > + > +In order to separate the device emulation code from the CPU emulation > +code, the device object code must run in a different process. There ar= e > +a couple of existing QEMU features that can run emulation code > +separately from the main QEMU process. These are examined below. There also is vfio+mdev. Right now a kernel interface, so (hardware-assisted) device emulation runs in the linux kernel. IIRC someone suggested to build a process->process interface based on the vfio api. What happened to that idea? > +If these devices are emulated by remote process =E2=80=9Cdisk-proc,=E2= =80=9D as > +described in the previous section, the QEMU command line would be: > + > + -device lsi53c895a,id=3Dscsi0,remote=3Ddisk-proc > + -device scsi-hd,drive=3Ddrive0,bus=3Dscsi0.0,scsi-id=3D0,remote=3D= disk-proc Does that work with the patch series? Why does qemu need to know about scsi-hd? cheers, Gerd