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[GH-41867][Part-2][eBPF] Add BPF tests for skip_tunnel flag and subnet-based routing interaction in hybrid mode#43631

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julianwiedmann merged 3 commits intocilium:mainfrom
anubhabMajumdar:topic/anmajumdar/bpf-tests
Jan 23, 2026
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[GH-41867][Part-2][eBPF] Add BPF tests for skip_tunnel flag and subnet-based routing interaction in hybrid mode#43631
julianwiedmann merged 3 commits intocilium:mainfrom
anubhabMajumdar:topic/anmajumdar/bpf-tests

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@anubhabMajumdar anubhabMajumdar commented Jan 8, 2026 •
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Description

The motivation behind adding a new routing mode is discussed in this CFP .

Part 1 introduces the data path changes - #41868 .

Key Changes

  1. Move hybrid_routing_enabled from node.h to subnet.h
  2. Add load test for the above configuration
  3. Adds comprehensive BPF tests to validate the interaction between the skip_tunnel flag and subnet-based routing in Cilium's egress datapath.

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Fixes: #41867

@maintainer-s-little-helper maintainer-s-little-helper bot added the dont-merge/needs-release-note-label The author needs to describe the release impact of these changes. label Jan 8, 2026
@joestringer joestringer added the release-note/ci This PR makes changes to the CI. label Jan 8, 2026
@maintainer-s-little-helper maintainer-s-little-helper bot removed the dont-merge/needs-release-note-label The author needs to describe the release impact of these changes. label Jan 8, 2026
@anubhabMajumdar anubhabMajumdar force-pushed the topic/anmajumdar/bpf-tests branch from 01f797c to 4caa4fd Compare January 9, 2026 00:42
@anubhabMajumdar anubhabMajumdar changed the title Topic/anmajumdar/bpf-tests [GH-41867][Part-2][eBPF] Add BPF tests for skip_tunnel flag and subnet-based routing interaction in hybrid mode Jan 9, 2026
@anubhabMajumdar anubhabMajumdar mentioned this pull request Jan 9, 2026
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anubhabMajumdar commented Jan 9, 2026

/test

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anubhabMajumdar commented Jan 9, 2026

github.com/cilium/cilium/pkg/maps/ctmap/gc.TestGCEnableDualStack failed in the last run, but I ran it multiple times locally and it passes. Will retry once more.

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anubhabMajumdar commented Jan 9, 2026

/ci-integration

@anubhabMajumdar anubhabMajumdar marked this pull request as ready for review January 9, 2026 03:47
@anubhabMajumdar anubhabMajumdar requested review from a team as code owners January 9, 2026 03:47
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anubhabMajumdar commented Jan 9, 2026

cc @julianwiedmann

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anubhabMajumdar commented Jan 15, 2026

Hi @YutaroHayakawa , added BPF tests for this last change - #41868 . Thanks!

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anubhabMajumdar commented Jan 16, 2026

/ci-l7

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anubhabMajumdar commented Jan 20, 2026

/ci-l7

@anubhabMajumdar anubhabMajumdar force-pushed the topic/anmajumdar/bpf-tests branch from 4caa4fd to 1300171 Compare January 21, 2026 21:47
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anubhabMajumdar commented Jan 21, 2026

/test

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anubhabMajumdar commented Jan 22, 2026

  • ci-verifier is passing locally, I think this one failed intermittently
  • ci-l7 is failing on a different test, checking sysdump it seems unrelated to this change

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anubhabMajumdar commented Jan 22, 2026

/ci-verifier

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anubhabMajumdar commented Jan 22, 2026

/ci-ipsec-e2e

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anubhabMajumdar commented Jan 22, 2026

/ci-delegated-ipam

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anubhabMajumdar commented Jan 22, 2026

/ci-l7

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smagnani96 commented Jan 22, 2026

This needs to be rebased to last main for:

@smagnani96 smagnani96 added dont-merge/needs-rebase This PR needs to be rebased because it has merge conflicts. area/CI Continuous Integration testing issue or flake area/datapath Impacts bpf/ or low-level forwarding details, including map management and monitor messages. labels Jan 22, 2026
@anubhabMajumdar
Move hybrid_routing_enabled config from Node to Subnet
fc03d2b 
Relocate hybrid_routing_enabled configuration from the Node
config to subnet.h where it's used. This provides better
scoping and allows per-program control of the feature.

Signed-off-by: Anubhab Majumdar <anmajumdar@microsoft.com>
@anubhabMajumdar
datapath/loader: Add HybridRoutingEnabled to BPF load tests
a39d10a 
Extend LXC and host BPF load test permutations to include
HybridRoutingEnabled configuration option.

Signed-off-by: Anubhab Majumdar <anmajumdar@microsoft.com>
@anubhabMajumdar
bpf/tests: Add subnet-based routing tests for hybrid routing
2ab793a 
Add test cases for skip_tunnel flag interaction with
subnet-based routing.

Signed-off-by: Anubhab Majumdar <anmajumdar@microsoft.com>
@anubhabMajumdar anubhabMajumdar force-pushed the topic/anmajumdar/bpf-tests branch from 1300171 to 2ab793a Compare January 22, 2026 17:35
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anubhabMajumdar commented Jan 22, 2026

/test

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YutaroHayakawa commented Jan 22, 2026

@ysksuzuki Could you please take a look at this?

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anubhabMajumdar commented Jan 23, 2026

/ci-clustermesh

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julianwiedmann approved these changes Jan 23, 2026
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lgtm, thank you!

@julianwiedmann julianwiedmann removed the dont-merge/needs-rebase This PR needs to be rebased because it has merge conflicts. label Jan 23, 2026
@julianwiedmann julianwiedmann added this pull request to the merge queue Jan 23, 2026
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julianwiedmann reviewed Jan 23, 2026
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bpf/tests/lib/subnet.h
Comment on lines +16 to +21
struct subnet_key key = {
.lpm_key.prefixlen = SUBNET_PREFIX_LEN(mask_size),
.family = ENDPOINT_KEY_IPV4,
.ip4 = addr,
};

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Please also take a moment to wire up the map structs into bpf/bpf_alignchecker.c, and consider this in the controlplane code. To ensure that both sides operate with the same perspective wrt struct layout.

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Thanks, will do!

Merged via the queue into cilium:main with commit 8dfc5e5 Jan 23, 2026
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@anubhabMajumdar anubhabMajumdar mentioned this pull request Feb 11, 2026
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@julianwiedmann julianwiedmann julianwiedmann approved these changes

@YutaroHayakawa YutaroHayakawa YutaroHayakawa approved these changes

@rgo3 rgo3 rgo3 approved these changes

@ysksuzuki ysksuzuki Awaiting requested review from ysksuzuki ysksuzuki is a code owner automatically assigned from cilium/sig-datapath

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Add hybrid routing to Cilium

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@anubhabMajumdar @smagnani96 @YutaroHayakawa @rgo3 @julianwiedmann @joestringer