kernel/linux.git/tools/testing/selftests/drivers/net/gro.py, branch linux-7.1.y

selftests: drv-net: gro: add a test for bad IPv4 csum

2026-04-03T22:05:45+00:00

We have a test for coalescing with bad TCP checksum, let's also test bad IPv4 header checksum. Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260402210000.1512696-9-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests: drv-net: gro: test ip6ip6

2026-04-03T22:05:44+00:00

We explicitly test ipip encap. Let's add ip6ip6, too. Having just ipip seems like favoring IPv4 which we should not do :) Testing all combinations is left for future work, not sure it's actually worth it. Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260402210000.1512696-8-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests: drv-net: gro: add 1 byte payload test

2026-04-03T22:05:43+00:00

Small IPv4 packets get padded to 60B, this may break / confuse some buggy implementations. Add a test to coalesce a 1B payload. Keep this separate from the lrg_sml test because I suspect some implementations may not handle this case (treat padded frames as ineligible for coalescing). Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260402210000.1512696-3-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests: drv-net: gro: add data burst test case

2026-04-03T22:05:42+00:00

Add a test trying to induce a GRO context timeout followed by another sequence of packets for the same flow. The second burst arrives 100ms after the first one so any implementation (SW or HW) must time out waiting at that point. We expect both bursts to be aggregated successfully but separately. Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260402210000.1512696-2-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests: drv-net: gro: add a test for GRO depth

2026-03-19T23:57:29+00:00

Reuse the long sequence test to max out the GRO contexts. Repeat for a single queue, 8 queues, and default number of queues but flow steering to just one. The SW GRO's capacity should be around 64 per queue (8 buckets, up to 8 skbs in a chain). Link: https://patch.msgid.link/20260318033819.1469350-7-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests: net: move gro to lib for HW vs SW reuse

2026-03-19T23:57:28+00:00

The gro.c packet sender is used for SW testing but bulk of incoming new tests will be HW-specific. So it's better to put them under drivers/net/hw/, to avoid tip-toeing around netdevsim. Move gro.c to lib so we can reuse it. Reviewed-by: Petr Machata Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260318033819.1469350-2-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests/net: gro: add self-test for TCP CWR flag

2026-02-03T14:13:24+00:00

Currently, GRO does not flush packets when the CWR bit is set. A corresponding self-test is being added, in which the CWR flag is set for two consecutive packets, but the first packet with the CWR flag set will not be flushed immediately. +===================+==========+===============+===========+ | Packet id | CWR flag | Payload | Flushing? | +===================+==========+===============+===========+ | 0 | 0 | PAYLOAD_LEN | 0 | | ... | 0 | PAYLOAD_LEN | 1 | +-------------------+----------+---------------+-----------+ | NUM_PACKETS/2 - 1 | 1 | payload_len | 0 | | NUM_PACKETS/2 | 1 | payload_len | 1 | +-------------------+----------+---------------+-----------+ | ... | 0 | PAYLOAD_LEN | 0 | | NUM_PACKETS | 0 | PAYLOAD_LEN | 1 | +===================+==========+===============+===========+ Signed-off-by: Chia-Yu Chang Acked-by: Paolo Abeni Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20260131222515.8485-4-chia-yu.chang@nokia-bell-labs.com Signed-off-by: Paolo Abeni

selftests: drv-net: gro: break out all individual test cases

2026-01-14T01:54:01+00:00

GRO test groups the cases into categories, e.g. "tcp" case checks coalescing in presence of: - packets with bad csum, - sequence number mismatch, - timestamp option value mismatch, - different TCP options. Since we now have TAP support grouping the cases like that lowers our reporting granularity. This matters even more for NICs performing HW GRO and LRO since it appears that most implementation have _some_ bugs. Flagging the whole group of tests as failed prevents us from catching regressions in the things that work today. Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260113000740.255360-7-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests: drv-net: gro: run the test against HW GRO and LRO

2026-01-14T01:54:01+00:00

Run the test against HW GRO and LRO. NICs I have pass the base cases. Interestingly all are happy to build GROs larger than 64k. Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260113000740.255360-6-kuba@kernel.org Signed-off-by: Jakub Kicinski

selftests: drv-net: gro: improve feature config

2026-01-14T01:54:01+00:00

We'll need to do a lot more feature handling to test HW-GRO and LRO. Clean up the feature handling for SW GRO a bit to let the next commit focus on the new test cases, only. Make sure HW GRO-like features are not enabled for the SW tests. Be more careful about changing features as "nothing changed" situations may result in non-zero error code from ethtool. Don't disable TSO on the local interface (receiver) when running over netdevsim, we just want GSO to break up the segments on the sender. Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260113000740.255360-5-kuba@kernel.org Signed-off-by: Jakub Kicinski