[libvirt] [PATCH 0/6] handle NIC_RX_FILTER_CHANGED events from qemu

[Amos Kong]

On Wed, Sep 24, 2014 at 05:50:50AM -0400, Laine Stump wrote:
> These patches set up an event handler for qemu's NIC_RX_FILTER_CHANGED
> event, which is sent whenever a guest makes a change to a network
> device's unicast/multicast filter, vlan table, or MAC address.

Not 'whenever', if first event isn't processed by querying rx-filter
of that interface, then qemu won't emit NIC_RX_FILTER_CHANGED event
for upcoming change of that interface.

First NIC_RX_FILTER_CHANGED event of each interfaces can be emitted
unconditionally.
 
> The handler checks if it is appropriate to respond to the
> NIC_RX_FILTER_CHANGED event (based on device type and configuration)
> and takes appropriate action. Currently it checks if the guest
> interface has been configured with trustGuestRxFilters='yes' (defaults
> to 'no' for security reasons), and if the host side device is
> macvtap. If so, and the MAC address on the guest has changed, the MAC
> address of the macvtap device is changed to match.
> 
> The result of this is that networking from the guest will continue to
> work if the mac address of a macvtap-connected network device is
> changed from within the guest, as long as trustGuestRxFilters='yes'
> (previously changing the MAC address in the guest would break
> networking).
> 
> I still need to add code to compare the old and new unicast and
> multicast lists and program the filters in the macvtap to match the
> guest, and to check for a non-empty vlan table and handle that
> (currently that means just setting promiscuous mode on the macvtap),
> but that can come in a followup series.
> 
> Laine Stump (6):
>   conf: add trustGuestRxFilters attribute to network and domain
>     interface
>   network: set interface actual trustGuestRxFilters from
>     network/portgroup
>   util: define virNetDevRxFilter and basic utility functions
>   qemu: qemuMonitorQueryRxFilter - retrieve guest netdev rx-filter
>   qemu: setup infrastructure to handle NIC_RX_FILTER_CHANGED event
>   qemu: change macvtap device MAC address in response to
>     NIC_RX_FILTER_CHANGED
> 
>  docs/formatdomain.html.in                          |  38 +++-
>  docs/formatnetwork.html.in                         |  28 ++-
>  docs/schemas/domaincommon.rng                      |   5 +
>  docs/schemas/network.rng                           |  10 +
>  src/conf/domain_conf.c                             |  42 ++++
>  src/conf/domain_conf.h                             |   3 +
>  src/conf/network_conf.c                            |  35 ++++
>  src/conf/network_conf.h                            |   2 +
>  src/libvirt_private.syms                           |   9 +
>  src/network/bridge_driver.c                        |  11 +
>  src/qemu/qemu_domain.h                             |   1 +
>  src/qemu/qemu_driver.c                             | 105 ++++++++++
>  src/qemu/qemu_monitor.c                            |  39 ++++
>  src/qemu/qemu_monitor.h                            |  11 +
>  src/qemu/qemu_monitor_json.c                       | 232 +++++++++++++++++++++
>  src/qemu/qemu_monitor_json.h                       |   3 +
>  src/qemu/qemu_process.c                            |  42 ++++
>  src/util/virnetdev.c                               |  40 ++++
>  src/util/virnetdev.h                               |  57 ++++-
>  tests/Makefile.am                                  |   3 +
>  tests/networkxml2xmlin/vepa-net.xml                |   4 +-
>  tests/networkxml2xmlout/vepa-net.xml               |   4 +-
>  .../qemuxml2argv-net-virtio-network-portgroup.xml  |   4 +-
>  23 files changed, 711 insertions(+), 17 deletions(-)
> 
> -- 
> 1.9.3

-- 
			Amos.