Unable to execute the tests on latest upstream kernel

[sidchintamaneni]

I'm experiencing issues while testing bpf_performance on the latest upstream kernel. The program fails with the following error:

./bpf_performance_runner -i tests.yml -t "Baseline"
Error: Program returned unexpected result 4294967274 in test Baseline expected 0

The test configuration shows:

=== TEST CONFIGURATION ===
Test name: Baseline
ELF file: baseline.o
Iteration count: 10000000
Batch size: 64
Pass data: 0
Pass context: 1
Expected result: 0
CPU count: 1

The program is returning -EINVAL (error code -22). After some debugging, I found that the error originates from this line: https://elixir.bootlin.com/linux/v6.18-rc5/source/net/bpf/test_run.c#L1231

The issue appears to be that bpf_performance_runner doesn't properly support the BPF_F_TEST_XDP_LIVE_FRAMES flag. I'm curious about which kernel versions are officially supported by this tool.

Since this tool supports both Windows and Linux, I'm uncertain whether BPF_F_TEST_XDP_LIVE_FRAMES and related XDP functionality are implemented on the Windows side to make changes to the tool.

Probably need similar hack like HAS_BPF_TEST_RUN_OPTS_BATCH_SIZE.
Also, I am curious why you chose xdp to run bpf_prog_test_run

Thanks in advance!

[Alan-Jowett]

Thanks for this report. Can you explain to me what this flag does? I am prohibited from inspecting GPL BPF code or I would look myself.

[sidchintamaneni]

ok I can help you out in that case.

BPF_F_TEST_XDP_LIVE_FRAMES flag enables userspace constructed test packets to flow through the kernel network stack as if it arrived on the network interface.