From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Graf Subject: Re: [Qemu-devel] [PATCH] Inter-VM shared memory PCI device Date: Mon, 08 Mar 2010 11:57:18 +0100 Message-ID: <4B94D80E.1060800@suse.de> References: <1267833161-25267-1-git-send-email-cam@cs.ualberta.ca> <1267833161-25267-2-git-send-email-cam@cs.ualberta.ca> <201003072254.00040.paul@codesourcery.com> <20100308014537.GA24024@shareable.org> <852A0015-DEAB-4FEF-862B-FDE35AEC9820@suse.de> <20100308095456.GC2869@shareable.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Paul Brook , "qemu-devel@nongnu.org" , Cam Macdonell , "kvm@vger.kernel.org" To: Jamie Lokier Return-path: Received: from cantor.suse.de ([195.135.220.2]:47146 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754037Ab0CHK5U (ORCPT ); Mon, 8 Mar 2010 05:57:20 -0500 In-Reply-To: <20100308095456.GC2869@shareable.org> Sender: kvm-owner@vger.kernel.org List-ID: Jamie Lokier wrote: > Alexander Graf wrote: > >> Or we could put in some code that tells the guest the host shm >> architecture and only accept x86 on x86 for now. If anyone cares for >> other combinations, they're free to implement them. >> >> Seriously, we're looking at an interface designed for kvm here. Let's >> please keep it as simple and fast as possible for the actual use case, >> not some theoretically possible ones. >> > > The concern is that a perfectly working guest image running on kvm, > the guest being some OS or app that uses this facility (_not_ a > kvm-only guest driver), is later run on qemu on a different host, and > then mostly works except for some silent data corruption. > > That is not a theoretical scenario. > > Well, the bit with this driver is theoretical, obviously :-) > But not the bit about moving to a different host. > I agree. Hence there should be a safety check so people can't corrupt their data silently. Alex