From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:41474 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757279AbbJVNBF (ORCPT ); Thu, 22 Oct 2015 09:01:05 -0400 Message-ID: <1445518861.4059.869.camel@redhat.com> Subject: Re: [Qemu-devel] [RFC Patch 00/12] IXGBE: Add live migration support for SRIOV NIC From: Alex Williamson To: "Michael S. Tsirkin" Cc: Or Gerlitz , emil.s.tantilov@intel.com, kvm@vger.kernel.org, linux-pci@vger.kernel.org, qemu-devel@nongnu.org, Jesse Brandeburg , carolyn.wyborny@intel.com, "Skidmore, Donald C" , agraf@suse.de, matthew.vick@intel.com, intel-wired-lan@lists.osuosl.org, Jeff Kirsher , yang.z.zhang@intel.com, Mitch Williams , nrupal.jani@intel.com, bhelgaas@google.com, Lan Tianyu , Linux Netdev List , Shannon Nelson , eddie.dong@intel.com, Linux Kernel , john.ronciak@intel.com, Paolo Bonzini Date: Thu, 22 Oct 2015 07:01:01 -0600 In-Reply-To: <20151022123252.GA19940@redhat.com> References: <1445445464-5056-1-git-send-email-tianyu.lan@intel.com> <1445455227.4059.867.camel@redhat.com> <20151022123252.GA19940@redhat.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org List-ID: On Thu, 2015-10-22 at 15:32 +0300, Michael S. Tsirkin wrote: > On Wed, Oct 21, 2015 at 01:20:27PM -0600, Alex Williamson wrote: > > The trouble here is that the VF needs to be unplugged prior to the start > > of migration because we can't do effective dirty page tracking while the > > device is connected and doing DMA. > > That's exactly what patch 12/12 is trying to accomplish. > > I do see some problems with it, but I also suggested some solutions. I was replying to: > So... what would you expect service down wise for the following > solution which is zero touch and I think should work for any VF > driver: And then later note: "Here it's done via an enlightened guest driver."