Re: [PATCH bpf-next 4/5] selftests/bpf: integrate test_tc_tunnel.sh tests into test_progs

["Alexis Lothoré" <alexis.lothore@bootlin.com>]

Hello Martin,

On Sat Oct 18, 2025 at 2:18 AM CEST, Martin KaFai Lau wrote:
> On 10/17/25 7:29 AM, Alexis Lothoré (eBPF Foundation) wrote:
>> The test_tc_tunnel.sh script checks that a large variety of tunneling
>> mechanisms handled by the kernel can be handled as well by eBPF
>> programs. While this test shares similarities with test_tunnel.c (which
>> is already integrated in test_progs), those are testing slightly
>> different things:
>> - test_tunnel.c creates a tunnel interface, and then get and set tunnel
>>    keys in packet metadata, from BPF programs.
>> - test_tc_tunnels.sh manually parses/crafts packets content
>> 
>> Bring the tests covered by test_tc_tunnel.sh into the test_progs
>> framework, by creating a dedicated test_tc_tunnel.sh. This new test
>> defines a "generic" runner which, for each test configuration:
>> - will bring the relevant veth pair, each of those isolated in a
>>    dedicated namespace
>> - will check that traffic will fail if there is only an encapsulating
>>    program attached to one veth egress
>> - will check that traffic succeed if we enable some decapsulation module
>>    on kernel side
>> - will check that traffic still succeeds if we replace the kernel
>>    decapsulation with some eBPF ingress decapsulation.
>> 
>> Example of the new test execution:
>> 
>>    # ./test_progs -a tc_tunnel
>>    #447/1   tc_tunnel/ipip_none:OK
>>    #447/2   tc_tunnel/ipip6_none:OK
>>    #447/3   tc_tunnel/ip6tnl_none:OK
>>    #447/4   tc_tunnel/sit_none:OK
>>    #447/5   tc_tunnel/vxlan_eth:OK
>>    #447/6   tc_tunnel/ip6vxlan_eth:OK
>>    #447/7   tc_tunnel/gre_none:OK
>>    #447/8   tc_tunnel/gre_eth:OK
>>    #447/9   tc_tunnel/gre_mpls:OK
>>    #447/10  tc_tunnel/ip6gre_none:OK
>>    #447/11  tc_tunnel/ip6gre_eth:OK
>>    #447/12  tc_tunnel/ip6gre_mpls:OK
>>    #447/13  tc_tunnel/udp_none:OK
>>    #447/14  tc_tunnel/udp_eth:OK
>>    #447/15  tc_tunnel/udp_mpls:OK
>>    #447/16  tc_tunnel/ip6udp_none:OK
>>    #447/17  tc_tunnel/ip6udp_eth:OK
>>    #447/18  tc_tunnel/ip6udp_mpls:OK
>>    #447     tc_tunnel:OK
>>    Summary: 1/18 PASSED, 0 SKIPPED, 0 FAILED
>
> Thanks for working on this!

Thanks for the prompt and detailed review !
>
> One high level comment is to minimize switching netns to make the test 
> easier to follow.

Yeah, all the NS switches make the overall setup a bit tedious. I'll give a
try to your suggestions and see if we can reduce the number of NS
open/close pairs.

Alexis

-- 
Alexis Lothoré, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com