Re: [bug] cxgb4: vrf stopped working with cxgb4 card

[AMG Zollner Robert <robert@cloudmedia.eu>]

Yes, I was enslaving while the interface was up.

Just tested some of the builds that where not working earlier and they 
are working if I keep the interface down when enslaving as you suggested.

Is this the expected behavior?

Thank you,
Zollner Robert


On 04.06.2018 21:17, David Ahern wrote:
> On 6/4/18 8:03 AM, AMG Zollner Robert wrote:
>> I have noticed that vrf is not working with kernel v4.15.0 but was
>> working with v4.13.0 when using cxgb4 Chelsio driver (T520-cr)
>>
>> Setup:
>> Two metal servers with a T520-cr card each, directly connected without a
>> switch in between.
>>
>>         SVR1  only ipfwd                 SVR2     with vrf
>> .----------------------------. .----------------------------------.
>> |                            |         |             |
>> |    192.168.8.1 [  ens2f4]--|---------|--[ens1f4] 192.168.8.2   |
>> |    192.168.9.1 [ens2f4d1]--|---------|--<ens1f4d1> 192.168.9.2 VRF=10   |
>> `----------------------------' `----------------------------------'
>>
>> When vrf is not working there are no error messages (dmesg or iproute
>> commands), tcpdump on the interface (SVR2.ens1f4d1) enslaved in vrf 10
>> shows packets(arp req/reply) coming in and going out, but outgoing
>> packets(arp reply) do not reach the other server SVR1.ens2f4d1
>>
>>
>> Bisect:
>> Found this commit to be the problem after doing a git bisect between
>> v4.13..v4.15:
>>
>> commit ba581f77df23c8ee70b372966e69cf10bc5453d8
>> Author: Ganesh Goudar <ganeshgr@chelsio.com>
>> Date:   Sat Sep 23 16:07:28 2017 +0530
>>
>>      cxgb4: do DCB state reset in couple of places
>>
>>      reset the driver's DCB state in couple of places
>>      where it was missing.
>>
>>
>> A bisect step was considered good when:
>> - successful ping from SVR1 to SVR2.ens1f4d1 vrf interface
>> - successful ping from SVR2 global to SVR2 vrf interface trough SVR1(l3
>> forwarding) (this check was redundant,both tests fail or pass simultaneous)
>>
>> The problem is still present on recent kernels also, checked v4.16.0 and
>> v4.17.rc7
>>
>> Disabling DCB for the card support fixes the problem ( Compiling kernel
>> with "CONFIG_CHELSIO_T4_DCB=n")
>>
> Are you doing the VRF enslave while it is up?
>
> If so, does it work ok if you change the sequence:
>
> ip li set ens1f4d1 down
> ip li set ens1f4d1 master <VRF>
> ip li set ens1f4d1 up