From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: pci passthrough - VF reset at boot is dropping assigned MAC Date: Mon, 25 Apr 2011 14:29:29 -0600 Message-ID: <4DB5D9A9.4040503@gmail.com> References: <4DB5A13B.4050804@gmail.com> <1303749455.3431.21.camel@x201> <4DB5A44F.6040304@gmail.com> <1303752659.3431.31.camel@x201> <4DB5B7AE.8010900@gmail.com> <1303756594.3431.55.camel@x201> <4DB5C78A.1030505@gmail.com> <1303759116.3431.59.camel@x201> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: KVM mailing list To: Alex Williamson Return-path: Received: from mail-pw0-f46.google.com ([209.85.160.46]:55417 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932552Ab1DYU3c (ORCPT ); Mon, 25 Apr 2011 16:29:32 -0400 Received: by pwi15 with SMTP id 15so5547pwi.19 for ; Mon, 25 Apr 2011 13:29:32 -0700 (PDT) In-Reply-To: <1303759116.3431.59.camel@x201> Sender: kvm-owner@vger.kernel.org List-ID: On 04/25/11 13:18, Alex Williamson wrote: >>> I don't see this happening on my system, once manually set the mac never >>> changes. I can restart and reset the VM and the host and guest both >>> continue seeing the set mac address. I tested it with both a recent >>> rhel6.1 host kernel as well as upstream 2.6.39-rc4. If I switch to a VF >>> with an unset mac, those will change on each VM reset or restart. >> >> Blacklist igbvf in the host and you will. That must be the difference: I >> was preventing the vf driver from loading in the host -- it's not needed >> there, so why load it? > > I already have it blacklisted. It's not needed if you're using the VFs > they way we are, but there are other uses. > >> I rebooted for a fresh run. Loaded the igbvf driver before starting the >> VM using my tools. With the igbvf driver loaded in the host the MAC >> address for the VF was not reset. >> >> As for why I blacklisted it -- udev. What a PITA with VFs. I saw the >> feature for Fedora 15 which should address this. > > Yes, my VM is up to renaming the VFs eth1340 since the mac changes every > boot. I'm still confused though as I did a whole round of testing after > a reboot where igbvf was never loaded and the set mac address stuck > across VM restarts and resets. > > Alex > The resetting of the VM MAC address is fixed in 2.6.39-rc4, so it's a Fedora 14, 2.6.35.12 problem. David