From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:58871) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TIHXg-0007Bm-UF for qemu-devel@nongnu.org; Sun, 30 Sep 2012 07:18:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TIHXf-00029u-Uk for qemu-devel@nongnu.org; Sun, 30 Sep 2012 07:18:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:13509) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TIHXf-00029q-L7 for qemu-devel@nongnu.org; Sun, 30 Sep 2012 07:18:35 -0400 Message-ID: <50682A86.2040909@redhat.com> Date: Sun, 30 Sep 2012 13:18:30 +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> <5067FF3E.7040003@redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 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: liu ping fan Cc: Jan Kiszka , Marcelo Tosatti , "qemu-devel@nongnu.org" , Anthony Liguori , Paolo Bonzini On 09/30/2012 10:48 AM, liu ping fan wrote: > On Sun, Sep 30, 2012 at 4:13 PM, Avi Kivity wrote: >> On 09/29/2012 11:20 AM, liu ping fan wrote: >>> >>> Do we have iommus in qemu now, >> >> We do, but they're hacked into the scsi layer, see hw/sun4m_iommu.c. I >> don't know if it's a standalone iommu on real hardware or whether it is >> part of the HBA. >> >>> since there are no separate phys_maps >>> for real address and dev's virt address, and I think the iommu is only >>> needed by host, not guest, so need not emulated by qemu. >> >> Eventually we will emulate iommus for x86 too, so we need to consider them. >> > For nested guest? The address translation is like nested mmu? Yes. -- error compiling committee.c: too many arguments to function