Re: [RFC bpf-next] selftests/bpf: Test XDP LRU hash rolling-window map updates

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] bpf: unnecessary FD validation for skeleton-generated fields
--

commit 382196b03e5bc2ae66b47677cc5a9357a9560542
Author: Anil Kaushik <anilkaushikwireless@gmail.com>

selftests/bpf: Test XDP LRU hash rolling-window map updates

This commit adds a small XDP program that writes packet lengths into
BPF_MAP_TYPE_LRU_HASH at seq % AGGREGATION_WINDOW. It also adds a test_progs
case using bpf_prog_test_run to check wrap, parse-fail isolation, and 5-tuple
isolation.

> diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_lru_window.c b/tools/testing/selftests/bpf/prog_tests/xdp_lru_window.c
> new file mode 100644
> index 0000000000000..fffbb4a0418ef
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/xdp_lru_window.c
[ ... ]
> +void test_xdp_lru_window(void)
> +{
> +	skel = xdp_lru_window__open_and_load();
> +	if (!ASSERT_OK_PTR(skel, "open_and_load"))
> +		return;
> +
> +	prog_fd = bpf_program__fd(skel->progs.xdp_lru_window);
> +	map_fd = bpf_map__fd(skel->maps.flow_table);
> +	if (!ASSERT_GE(prog_fd, 0, "prog_fd") ||
> +	    !ASSERT_GE(map_fd, 0, "map_fd"))
> +		goto out;

[Severity: Low]
Are these ASSERT_GE() checks necessary in test_xdp_lru_window()?

Since the skeleton is successfully initialized with
xdp_lru_window__open_and_load(), the BPF selftest skeleton framework
guarantees that all generated map and program fields contain valid file
descriptors.

Validating prog_fd and map_fd manually here appears redundant and contrary
to the established skeleton API contract. Could we remove this check?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260917135433.2260048-1-anilkaushikwireless@gmail.com?part=1