[libvirt] libvirt-tck test failure after commit b3d06987

[Mike Latimer]

Hi Vasiliy,

On Thursday, June 02, 2016 02:29:51 PM Vasiliy Tolstov wrote:
> 2016-06-02 8:13 GMT+03:00 Jim Fehlig <jfehlig at suse.com>:
> > We've noticed libvirt-tck test 100-apply-verify-host.t failing recently on
> > libvirt.git master and I finally got around to bisecting it to commit
> > b3d06987. I haven't looked at the test in detail, but it appears to
> > expect a broadcast address of 10.1.2.255, however finds an address of
> > 0.0.0.0 after commit b3d06987. I'm not terribly familiar with this code,
> > but the following hunk of b3d06987 looks suspect
> 
> Can you share me path where i can find this test?

Before you spend too much time figuring out that test, the problem can be seen 
outside the TCK framework by manually creating the network the test uses:

<network>
  <name>tck-testnet</name>
  <uuid>aadc8920-502a-4774-ac2b-cd382a204d06</uuid>
  <forward mode='nat'/>
  <bridge name='tck-testbr' stp='on' delay='0' />
  <ip address='10.1.2.1' netmask='255.255.255.0'>
    <dhcp>
      <range start='10.1.2.2' end='10.1.2.254' />
    </dhcp>
  </ip>
</network>

After creating the network, the TCK test verifies the network was setup 
properly by checking the output of iptables, ip, etc...  One of these tests 
checks the network address and broadcast address for the bridge. The expected 
values are 10.1.2.1/24 (IP address) and 10.1.2.255 (broadcast address). Under 
the current libvirt code, the broadcast address is not set, so the test fails 
to parse the output of `ip -o a` correctly, and the test fails. Checking the 
network setup manually shows the missing broadcast address:

# ip a show tck-testbr
82: tck-testbr: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue 
state DOWN group default qlen 1000
    link/ether 52:54:00:ec:41:9e brd ff:ff:ff:ff:ff:ff
    inet 10.1.2.1/24 scope global tck-testbr
       valid_lft forever preferred_lft forever

If there were a broadcast address, the inet line above should look like:
     inet 10.1.2.1/24 brd 10.1.2.255 scope global tck-testbr

ifconfig shows the broadcast address as 0.0.0.0:
#ifconfig
tck-testb Link encap:Ethernet  HWaddr 52:54:00:EC:41:9E  
          inet addr:10.1.2.1  Bcast:0.0.0.0  Mask:255.255.255.0
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

I haven't pulled any LAN traces yet, but the missing/0.0.0.0 broadcast address 
does not seem correct.

-Mike