Re: [libvirt] [PATCH] network: disallow <bandwidth>/<mac> for bridged/macvtap networks

On 24.01.2014 13:18, Laine Stump wrote: > https://bugzilla.redhat.com/show_bug.cgi?id=1057321 pointed out that > we weren't honoring the <bandwidth> element in libvirt networks using > <forward mode='bridge'/>. In fact, these networks are just a method of > giving a libvirt network name to an existing Linux host bridge on the > system, and even if it were technically possible for us to set > network-wide bandwidth limits for all the taps on a bridge, it's > probably not a polite thing to do since libvirt is just using a bridge > that was created by someone else for other purposes. So the proper > thing is to just log an error when someone tries to put a <bandwidth> > element in that type of network. > > While looking through the network XML documentation and comparing it > to the networkValidate function, I noticed that we also ignore the > presence of a mac address in the config, even though we do nothing > with it in this case either. > > This patch updates networkValidate() (which is called any time a > persistent network is defined, or a transient network created) to log > an error and fail if it finds either a <bandwidth> or <mac> element > and the network forward mode is anything except 'route'. 'nat', or > nothing. (Yes, neither of those elements is acceptable for any macvtap > mode, nor for a hostdev network). > > NB: This does *not* cause failure to start any existing network that > contains one of those elements, so someone might have erroneously > defined such a network in the past, and that network will continue to > function unmodified. I considered it too disruptive to suddenly break > working configs on the next reboot after a libvirt upgrade. > --- > src/network/bridge_driver.c | 19 ++++++++++++++++++- > 1 file changed, 18 insertions(+), 1 deletion(-) > > diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c > index 0b43a67..3b9b58d 100644 > --- a/src/network/bridge_driver.c > +++ b/src/network/bridge_driver.c > @@ -2407,8 +2407,17 @@ networkValidate(virNetworkDriverStatePtr driver, > virNetworkSetBridgeMacAddr(def); > } else { > /* They are also the only types that currently support setting > - * an IP address for the host-side device (bridge) > + * a MAC or IP address for the host-side device (bridge), DNS > + * configuration, or network-wide bandwidth limits. > */ > + if (def->mac_specified) { > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, > + _("Unsupported <mac> element in network %s " > + "with forward mode='%s'"), > + def->name, > + > virNetworkForwardTypeToString(def->forward.type)); > + return -1; > + } > if (virNetworkDefGetIpByIndex(def, AF_UNSPEC, 0)) { > virReportError(VIR_ERR_CONFIG_UNSUPPORTED, > _("Unsupported <ip> element in network %s " > @@ -2433,6 +2442,14 @@ networkValidate(virNetworkDriverStatePtr driver, > > virNetworkForwardTypeToString(def->forward.type)); > return -1; > } > + if (def->bandwidth) { > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, > + _("Unsupported network-wide <bandwidth> > element " > + "in network %s with forward mode='%s'"), > + def->name, > + > virNetworkForwardTypeToString(def->forward.type)); > + return -1; > + } > } > > /* We only support dhcp on one IPv4 address and > I think think this is exactly the opposite of what I've just pushed :)

I mean: commit 2996e6be19a13199ded7c2aa21039cca97318e01 Author: Michal Privoznik <mprivozn(a)redhat.com&gt; AuthorDate: Wed Jan 22 18:58:33 2014 +0100 Commit: Michal Privoznik <mprivozn(a)redhat.com&gt; CommitDate: Mon Jan 27 12:11:27 2014 +0100 networkAllocateActualDevice: Set QoS for bridgeless networks too https://bugzilla.redhat.com/show_bug.cgi?id=1055484 In the commit I'm trying to inherit network QoS to the interface that is just being created. Yes, it involves some magic but it works. I guess we need to agree if we want this approach or mine as they seem to be contradictionary.