From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [ANNOUNCE] Native Linux KVM tool Date: Fri, 08 Apr 2011 17:59:37 -0500 Message-ID: <4D9F9359.20708@codemonkey.ws> References: <1301592656.586.15.camel@jaguar> <4D982E89.8070502@redhat.com> <4D9847BC.9060906@redhat.com> <4D98716D.9040307@codemonkey.ws> <4D9873CD.3080207@redhat.com> <20110406093333.GB6465@elte.hu> <4D9E6F6E.9050709@codemonkey.ws> <4D9F150B.1030809@codemonkey.ws> <20110408192039.GJ29444@random.random> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Pekka Enberg , Ingo Molnar , Avi Kivity , linux-kernel@vger.kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, joro@8bytes.org, penberg@cs.helsinki.fi, asias.hejun@gmail.com, gorcunov@gmail.com To: Andrea Arcangeli Return-path: In-Reply-To: <20110408192039.GJ29444@random.random> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 04/08/2011 02:20 PM, Andrea Arcangeli wrote: > Hi Anthony, > > On Fri, Apr 08, 2011 at 09:00:43AM -0500, Anthony Liguori wrote: >> An example is ioport_ops. This maps directly to >> ioport_{read,write}_table in QEMU. Then you use ioport__register() to >> register entries in this table similar register_ioport_{read,write}() in >> QEMU. >> >> The use of a struct is a small improvement but the fundamental design is >> flawed because it models a view of hardware where all devices are >> directly connected to the CPU. This is not how hardware works at all. > Not sure if I've the whole picture on this but I see no answer to your > email and I found your remark above the most interesting. This is > because I thought the whole point of a native kvm tool was to go all > the paravirt way to provide max performance and maybe also depend on > vhost as much as possible. Yeah, if that's the goal, skip all the mini-BIOS junk and just rely on a PV kernel in the guest. I think a mini userspace that assumes that we can change the guest kernel and avoids having a ton of complexity to do things like CMOS emulation would be a really interesting thing to do. Regards, Anthony Liguori