From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:41817) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QKphK-0007mu-Lp for qemu-devel@nongnu.org; Fri, 13 May 2011 06:34:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QKphJ-0006dK-CN for qemu-devel@nongnu.org; Fri, 13 May 2011 06:34:18 -0400 Received: from mail-gw0-f45.google.com ([74.125.83.45]:43689) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QKphJ-0006d9-8s for qemu-devel@nongnu.org; Fri, 13 May 2011 06:34:17 -0400 Received: by gwb19 with SMTP id 19so977159gwb.4 for ; Fri, 13 May 2011 03:34:16 -0700 (PDT) Message-ID: <4DCD0925.60605@landley.net> Date: Fri, 13 May 2011 05:34:13 -0500 From: Rob Landley MIME-Version: 1.0 References: <4DCB486F.70509@landley.net> <4DCC8DE7.9050502@landley.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] -net interface association behavior change in current -git. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: blauwirbel@gmail.com, vpalatin@chromium.org, qemu-devel@nongnu.org On 05/13/2011 01:54 AM, Markus Armbruster wrote: > Rob Landley writes: > >> On 05/12/2011 09:10 AM, Markus Armbruster wrote: >>> Rob Landley writes: >>> >>>> In 1.14.0, if I did this: >>>> >>>> qemu -net nic,blah -net user -net nic,blah -net tun,blah >>>> >>>> Then the first nic would be -net user, and the second nic would be -net >>>> tun. In current -git, -net user attaches to the second interface and >>>> -net tun attaches to the first, I.E. the order is reversed. >>>> >>>> Either way the first -nic becomes eth0 in Linux and the second becomes >>>> eth1 (I can manually assign mac addresses in order to confirm which is >>>> which), but eth0 used to be the -net user interface and now eth1 is the >>>> -net user interface. >>>> >>>> I bisected this to commit 60c07d933c66c4b30a83b but I don't know why it >>>> changed the behavior, and I can't find _documentation_ on having >>>> multiple interfaces transports hooked up to the same qemu instance >>>> anyway. (It used to work, but possibly that was an accident?) >>>> >>>> Any ideas? >>> >>> Does it happen with -device and -netdev as well? >>> >>> See docs/qdev-device-use.txt for how to go from -net to -device. >> >> Read read read... >> >> That seems to be micromanaging PCI bus slot assignment, which isn't >> changed by this patch. The cards don't move around, nor does the >> association between cards and Linux eth0/eth1. What changes is which >> virtual LAN each virtual ethernet card is plugged into. (The virtual >> cat5 cable coming out of the card moves to a different switch.) > > I didn't mean to tell you "try using -device to juggle PCI addresses". > I meant to steer you away from QEMU VLANs, to find out whether they're a > factor in your problem. Possible, because non-VLAN uses a few different > code paths in QEMU. Sorry if I was too terse. > > In general, my advice is stay away from QEMU VLANs. Ok, now I'm confused. Before this, I wasn't using them. Now I am. What's the reason for avoiding them? (Also, I didn't see a way in -device to specify a network transport, just cards and their properties. Quite possibly I missed it...) >> (The fix was to tag everything with vlan arguments and manually manage >> the association.) > > Glad you got your problem solved. Solved, yes. Understood... less so than I thought, apparently? Rob