From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: vbus design points: shm and shm-signals Date: Mon, 24 Aug 2009 19:10:23 -0500 Message-ID: <4A932BEF.5080603@codemonkey.ws> References: <20090814154125.26116.70709.stgit@dev.haskins.net> <20090814154308.26116.46980.stgit@dev.haskins.net> <20090815103243.GA26749@elte.hu> <4A870964.9090408@codemonkey.ws> <4A8965E0.8050608@gmail.com> <4A89FF08.30509@codemonkey.ws> <4A8AA9BD.2070909@gmail.com> <4A8AB076.6080906@redhat.com> <4A8ACE1F.6020402@gmail.com> <20090818161434.GA15884@elte.hu> <4A8B7F17.6050100@gmail.com> <4A8E7D32.8040209@gmail.com> <4A92E3B1.5080002@codemonkey.ws> <4A92F158.9050003@gmail.com> <4A9328E3.3060106@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: alacrityvm-devel@lists.sourceforge.net, Ingo Molnar , Gregory Haskins , kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: Gregory Haskins Return-path: Received: from qw-out-2122.google.com ([74.125.92.25]:26129 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753934AbZHYAKY (ORCPT ); Mon, 24 Aug 2009 20:10:24 -0400 In-Reply-To: <4A9328E3.3060106@codemonkey.ws> Sender: kvm-owner@vger.kernel.org List-ID: Anthony Liguori wrote: > IOW, I can envision a model that looked like PCI -> virtio-pci -> > virtio-shm -> virtio-ring -> virtio-net Let me stress that what's important here is that devices target either virtio-ring or virtio-shm. If we had another transport, those drivers would be agnostic toward it. We really want to preserve the ability to use all devices over a PCI transport. That's a critical requirement for us. The problem with vbus as it stands today, is that it presents vbus -> virtio-ring -> virtio-net and allows drivers to target either virtio-ring or vbus directly. If a driver targets vbus directly, then the driver is no longer transport agnostic and we could not support that driver over PCI. Regards, Anthony Liguori