[ovs-dev] [PATCH] connmgr: Fix vswitchd abort when a port is added and the controller is down

[Miguel Angel Ajo Pelayo]

Wow, proper TDD!

Is it possible to get this backported at least down to 2.10 ?

Acked-by: Miguel Angel Ajo <majopela at redhat.com>

More context here: https://bugzilla.redhat.com/show_bug.cgi?id=1640045


On Wed, Oct 17, 2018 at 2:59 PM Numan Siddique <nusiddiq at redhat.com> wrote:

>
>
> On Wed, Oct 17, 2018 at 6:27 PM Miguel Angel Ajo Pelayo <
> majopela at redhat.com> wrote:
>
>> Wow, that was quick Numans,
>>
>> Did you try the negative of the test? (removing your patch on the C side
>> and trying the test
>> to make sure it fails?)
>>
>
> Yes. I actually started with the test to make sure it fails before working
> on the fix :)
>
> Thanks
> Numan
>
>
>>
>>
>>
>> On Wed, Oct 17, 2018 at 2:08 PM <nusiddiq at redhat.com> wrote:
>>
>>> From: Numan Siddique <nusiddiq at redhat.com>
>>>
>>> We see the below trace when a port is added to a bridge and the
>>> configured
>>> controller is down
>>>
>>> 0x00007fb002f8b207 in raise () from /lib64/libc.so.6
>>> 0x00007fb002f8c8f8 in abort () from /lib64/libc.so.6
>>> 0x00007fb004953026 in ofputil_protocol_to_ofp_version () from /lib64/
>>> libopenvswitch-2.10.so.0
>>> 0x00007fb00494e38e in ofputil_encode_port_status () from /lib64/
>>> libopenvswitch-2.10.so.0
>>> 0x00007fb004ef1c5b in connmgr_send_port_status () from
>>> /lib64/libofproto-2.10.so.0
>>> 0x00007fb004efa9f4 in ofport_install () from /lib64/libofproto-2.10.so.0
>>> 0x00007fb004efbfb2 in update_port () from /lib64/libofproto-2.10.so.0
>>> 0x00007fb004efc7f9 in ofproto_port_add () from
>>> /lib64/libofproto-2.10.so.0
>>> 0x0000556d540a3f95 in bridge_add_ports__ ()
>>> 0x0000556d540a5a47 in bridge_reconfigure ()
>>> 0x0000556d540a9199 in bridge_run ()
>>> 0x0000556d540a02a5 in main ()
>>>
>>> When connmgr detects that the connection to the controller is down, it
>>> resets the ofconn's protocol to 'OFPUTIL_P_NONE' and that's why we
>>> see the above abort. This patch fixes the issue by also checking the
>>> connection status before sending the port status in the
>>>  connmgr_send_port_status().
>>>
>>> The issue can be reproduced by running the test added in this patch
>>> without the fix.
>>>
>>> Signed-off-by: Numan Siddique <nusiddiq at redhat.com>
>>> ---
>>>  ofproto/connmgr.c |  3 ++-
>>>  tests/bridge.at   | 21 +++++++++++++++++++++
>>>  2 files changed, 23 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/ofproto/connmgr.c b/ofproto/connmgr.c
>>> index f78b4c5ff..02ba75938 100644
>>> --- a/ofproto/connmgr.c
>>> +++ b/ofproto/connmgr.c
>>> @@ -1624,7 +1624,8 @@ connmgr_send_port_status(struct connmgr *mgr,
>>> struct ofconn *source,
>>>      ps.reason = reason;
>>>      ps.desc = *pp;
>>>      LIST_FOR_EACH (ofconn, node, &mgr->all_conns) {
>>> -        if (ofconn_receives_async_msg(ofconn, OAM_PORT_STATUS, reason))
>>> {
>>> +        if (ofconn_receives_async_msg(ofconn, OAM_PORT_STATUS, reason)
>>> &&
>>> +            rconn_is_connected(ofconn->rconn)) {
>>>              struct ofpbuf *msg;
>>>
>>>              /* Before 1.5, OpenFlow specified that OFPT_PORT_MOD should
>>> not
>>> diff --git a/tests/bridge.at b/tests/bridge.at
>>> index 1c3618563..ee398bdb1 100644
>>> --- a/tests/bridge.at
>>> +++ b/tests/bridge.at
>>> @@ -79,3 +79,24 @@ AT_CHECK([ovs-vsctl --columns=status list controller
>>> | dnl
>>>  OVS_APP_EXIT_AND_WAIT([ovs-vswitchd])
>>>  OVS_APP_EXIT_AND_WAIT([ovsdb-server])
>>>  AT_CLEANUP
>>> +
>>> +AT_SETUP([bridge - add port after stopping controller])
>>> +OVS_VSWITCHD_START
>>> +
>>> +dnl Start ovs-testcontroller
>>> +ovs-testcontroller --detach punix:controller
>>> --pidfile=ovs-testcontroller.pid
>>> +OVS_WAIT_UNTIL([test -e controller])
>>> +
>>> +AT_CHECK([ovs-vsctl set-controller br0 unix:controller])
>>> +AT_CHECK([ovs-vsctl add-port br0 p1 -- set Interface p1 type=internal],
>>> [0], [ignore])
>>> +AT_CHECK([ovs-appctl -t ovs-vswitchd version], [0], [ignore])
>>> +
>>> +# Now kill the ovs-testcontroller
>>> +kill `cat ovs-testcontroller.pid`
>>> +OVS_WAIT_UNTIL([! test -e controller])
>>> +AT_CHECK([ovs-vsctl --no-wait add-port br0 p2 -- set Interface p2
>>> type=internal], [0], [ignore])
>>> +AT_CHECK([ovs-appctl -t ovs-vswitchd version], [0], [ignore])
>>> +
>>> +OVS_APP_EXIT_AND_WAIT([ovs-vswitchd])
>>> +OVS_APP_EXIT_AND_WAIT([ovsdb-server])
>>> +AT_CLEANUP
>>> --
>>> 2.17.2
>>>
>>> _______________________________________________
>>> dev mailing list
>>> dev at openvswitch.org
>>> https://mail.openvswitch.org/mailman/listinfo/ovs-dev
>>>
>>
>>
>> --
>> Miguel Ángel Ajo
>> OSP / Networking DFG, OVN Squad Engineering
>>
>

-- 
Miguel Ángel Ajo
OSP / Networking DFG, OVN Squad Engineering