From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:58358) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1THB1o-0001mU-Oo for qemu-devel@nongnu.org; Thu, 27 Sep 2012 06:09:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1THB1i-0001sG-O1 for qemu-devel@nongnu.org; Thu, 27 Sep 2012 06:09:08 -0400 Received: from mx1.redhat.com ([209.132.183.28]:10285) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1THB1i-0001sC-Fm for qemu-devel@nongnu.org; Thu, 27 Sep 2012 06:09:02 -0400 Message-ID: <506425B8.1040706@redhat.com> Date: Thu, 27 Sep 2012 12:08:56 +0200 From: Avi Kivity MIME-Version: 1.0 References: <50597D1F.3070607@redhat.com> <505991A2.6090709@siemens.com> <5059954A.50408@redhat.com> <50600F7B.5080106@redhat.com> <50602B0A.1020403@redhat.com> <50641976.3020405@redhat.com> <50641C5F.2030202@redhat.com> <50641DB8.9090903@redhat.com> <50641E08.4040602@redhat.com> In-Reply-To: <50641E08.4040602@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [big lock] Discussion about the convention of device's DMA each other after breaking down biglock List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Jan Kiszka , Marcelo Tosatti , liu ping fan , Anthony Liguori , "qemu-devel@nongnu.org" On 09/27/2012 11:36 AM, Paolo Bonzini wrote: > Il 27/09/2012 11:34, Avi Kivity ha scritto: >>> > virtio-net is per-spec not going through the iommu. >> What's that smell? A feature bit? > > Why is it a bad thing that it does not go through the iommu? You can't assign the device to nested guests or to guest userspace via vfio. Some guests may want to use the iommu even in the guest kernel context. -- error compiling committee.c: too many arguments to function