From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sheng Yang Subject: Re: [RFC PATCH] PCI pass-through fixups Date: Tue, 7 Apr 2009 14:25:22 +0800 Message-ID: <200904071425.23098.sheng@linux.intel.com> References: <1238789816.15558.399.camel@lappy> <20090407000210.GL27148@sequoia.sous-sol.org> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Chris Wright , kvm To: Alex Williamson Return-path: Received: from mga07.intel.com ([143.182.124.22]:37513 "EHLO azsmga101.ch.intel.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757453AbZDGGZ3 (ORCPT ); Tue, 7 Apr 2009 02:25:29 -0400 In-Reply-To: <20090407000210.GL27148@sequoia.sous-sol.org> Content-Disposition: inline Sender: kvm-owner@vger.kernel.org List-ID: On Tuesday 07 April 2009 08:02:10 Chris Wright wrote: > * Alex Williamson (alex.williamson@hp.com) wrote: > > I'm wondering if we need a spot for device specific fixups for PCI > > pass-through. In the example below, I want to expose a single port of > > an Intel 82571EB quad port copper NIC to a guest. It works great until > > I shutdown the guest, at which point the guest e1000e driver knows by > > the device ID that the NIC is a quad port, and blindly attempts to > > twiddle some bits on the bridge above it (that doesn't exist). > > And what happens? And the output of DEVICE_ASSIGNMENT_DEBUG=1 may help. And I don't have trouble here with another dual/quad port card by Intel, but not 82571EB. > > > Obviously some robustness could be added to the driver, but would it > > make sense to do something like below and automatically remap these > > devices to identical single port device IDs? Thanks, > > Sounds quite fragile to me. Same here... We'd better to know what's happened. (wow, you even know the single port ones' device ID... :) ) -- regards Yang, Sheng