On 21 Jan 2026, at 13:58, Ilya Maximets wrote:
> On 1/21/26 10:55 AM, Eelco Chaudron wrote:
>>
>>
>> On 20 Jan 2026, at 21:55, Ilya Maximets wrote:
>>
>>> On 1/20/26 11:17 AM, Eelco Chaudron wrote:
>>>> Add the '--len' option to 'ovs-ofctl compose-packet', which
>>>> allows extension of the generated packet.
>>>>
>>>> Fixes: 90b6e83beb60 ("tests: Fix NSH decap header test for real Ethernet
>>>> devices.")
>>>> Signed-off-by: Eelco Chaudron <[email protected]>
>>>> ---
>>>> v2: Use packet_expand() so packet length and checksums get
>>>> updated.
>>>>
>>>> tests/system-traffic.at | 4 ++--
>>>> utilities/ovs-ofctl.c | 30 +++++++++++++++++++++++++++---
>>>> 2 files changed, 29 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/tests/system-traffic.at b/tests/system-traffic.at
>>>> index 8f4fdf8b1..71a8afff2 100644
>>>> --- a/tests/system-traffic.at
>>>> +++ b/tests/system-traffic.at
>>>> @@ -9996,12 +9996,12 @@ dnl Send the NSH packet with TCP SYN payload from
>>>> p0(at_ns0) interface directed
>>>> dnl to p1(at_ns1) interface.
>>>> NS_CHECK_EXEC([at_ns0], [$PYTHON3 $srcdir/sendpkt.py p0 \
>>>> "$(ovs-ofctl compose-packet --bare 'NSH_HEADER')" \
>>>> - "$(ovs-ofctl compose-packet --bare 'TCP_SYN_PKT')"],
>>>> + "$(ovs-ofctl compose-packet --len 64 --bare 'TCP_SYN_PKT')"],
>>>> [0], [ignore])
>>>>
>>>> dnl Check the expected de-capsulated TCP packet on the egress interface
>>>> OVS_WAIT_UNTIL([ovs-pcap p1.pcap | grep -q \
>>>> - "^$(ovs-ofctl compose-packet --bare 'TCP_SYN_PKT')0*\$"])
>>>> + "^$(ovs-ofctl compose-packet --len 64 --bare 'TCP_SYN_PKT')\$"])
>>>
>>> Hrm. More I look at this, more I think we don't need the new option.
>>> The 'compose-packet' already adds 64 bytes of payload to normal packets,
>>> having an extra --len option feels a little awkward. It doesn't add them
>>> here, because it's a SYN packet that is not supposed to carry extra data.
>>> The hardware returns some l2 padding, which is not part of the actual
>>> packet, so it is fine.
>>>
>>> What we can do is either:
>>>
>>> 1. Keep everything as is - maybe add a comment that there is a possibility
>>> for extra l2 padding in case of running with a real hardware.
>>>
>>> 2. Remove the SYN flag and let the TCP packet have the 64 bytes of payload
>>> this way.
>>
>> I do not really have a preference. Maybe 1 and add a comment? For two, people
>> might wonder why we do not simulate using a tcp setup packet?
>>
>> Let me know, and I’ll send a patch adding the comment (although the commit
>> message already has it).
>
> I guess, let's defer/drop this change for now. Can revisit later if this
> comes up again.
Ok, will do.
_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev
