From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753076AbcLMDPQ (ORCPT ); Mon, 12 Dec 2016 22:15:16 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51604 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752173AbcLMDPO (ORCPT ); Mon, 12 Dec 2016 22:15:14 -0500 Date: Tue, 13 Dec 2016 05:15:13 +0200 From: "Michael S. Tsirkin" To: Alex Williamson Cc: Cao jin , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, izumi.taku@jp.fujitsu.com Subject: Re: [PATCH] vfio/pci: Support error recovery Message-ID: <20161213050950-mutt-send-email-mst@kernel.org> References: <1480246457-10368-1-git-send-email-caoj.fnst@cn.fujitsu.com> <584EAACD.9070800@cn.fujitsu.com> <20161212121216.1c385d65@t450s.home> <20161213002810-mutt-send-email-mst@kernel.org> <20161212154313.2ffdf4ab@t450s.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161212154313.2ffdf4ab@t450s.home> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 13 Dec 2016 03:15:14 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 12, 2016 at 03:43:13PM -0700, Alex Williamson wrote: > > So just don't do it then. Topology must match between host and guest, > > except maybe for the case of devices with host driver (e.g. PF) > > which we might be able to synchronize against. > > We're talking about host kernel level handling here. The host kernel > cannot defer the link reset to the user under the assumption that the > user is handling the devices in a very specific way. The moment we do > that, we've lost. The way is same as baremetal though, so why not? And if user doesn't do what's expected, we can do the full link reset on close. -- MST