If a tap device is not given an explicit MAC address it will generate
one randomly.
The behaviour of the Linux bridge is to pickup the lowest MAC address
of any port for use in for ARP, STP etc. If the tap device's randomly
generated MAC address happens to be the lowest then this can cause all
manner of strange networking glitches in both domain 0 and guests when
the bridge suddenly takes over from the previously used MAC address.
We choose FE:FF:FF:FF:FF:FF as it the numerically largest
non-broadcast address. This ensures that the physical NIC device's
port will have the lowest MAC address and therefore be the one picked
up by the bridge.
vif devices already have a MAC address of FE:FF:FF:FF:FF:FF set by
netback already but there is no harm in forcing it a second time in
the hotplug script.
tap devices are added by the "add" event and therefore we should call
setup_bridge_port then as well as for "online" which is caused by vif
devices.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
From: Anthony PERARD <anthony.perard@citrix.com>
This patch adds a second argument to vif-bridge script. It can be "vif"
or "tap". "vif" give the default behavior and "tap" just add the
interface to the found bridge when the action is "add".
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
tools/hotplug/Linux/vif-bridge | 20 ++++++---
tools/hotplug/Linux/vif-common.sh | 70 ++++++++++++++++++++++++---------
tools/hotplug/Linux/xen-backend.rules | 5 +-
tools/libxl/libxl.c | 6 +-
4 files changed, 70 insertions(+), 31 deletions(-)
- Have the buid system generate a file which exports the install paths
for the hotplug scripts and stubdom / stubdom-dm
- Move file generation code from tools/python/Makefile into a gmake
macro
in Config.mk to avoid maintenance of three duplicates each with its
own
tweaks and bugs
- Export gmake variables into ioemu as shell variables
for upcoming ioemu patches
- Do above as a gmake macro to avoid maintenance of several duplicates
- Adjust hotplug scripts to find the right xen binaries from the
install directory
- Adjust stubdom-dm to use the install directories
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Ian Campbell
Anthony Perard
Keir Fraser