[libvirt] [PATCHv3 0/2] Added waiting for DAD to finish for bridge address.

Maxim Perevedentsev mperevedentsev at virtuozzo.com
Tue Sep 29 10:16:08 UTC 2015

This is a fix for commit db488c79173b240459c7754f38c3c6af9b432970
dnsmasq main process which is relied on when waiting for DAD to complete
exits without actually waiting for DAD. This is dnsmasq daemon's task.

It seems to be a race that DAD finished before dnsmasq main process exited.
The above commit needs the execution to block until DAD finishes
for bridge IPv6 address because then it closes dummy tap device.
Thus we need to ensure this ourselves.

So we periodically poll the kernel using netlink and
check whether there are any IPv6 addresses assigned to bridge
which have 'tentative' state. After DAD is finished, execution continues.
I guess that is what dnsmasq was assumed to do.

We use netlink to dump information about existing IPv6 addresses. Netlink's
response is a multi-part message. Unfortunately, the current implementation
of virNetlink treats such messages as faulty and throws an error. So the patch 2/2
adds multi-part nelink response support.

Update v2: fixed syntax.
Update v3: moved to virnetdev.
Resend: These patches were ignored and buried long ago :-(

Maxim Perevedentsev (2):
  network: added waiting for DAD to finish for bridge address.
  netlink: add support for multi-part netlink messages.

 src/libvirt_private.syms    |   1 +
 src/network/bridge_driver.c |  35 +++++++++-
 src/util/virnetdev.c        | 160 ++++++++++++++++++++++++++++++++++++++++++++
 src/util/virnetdev.h        |   2 +
 src/util/virnetlink.c       |   4 +-
 5 files changed, 200 insertions(+), 2 deletions(-)


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