> selftests/bpf: Cover link info metadata on ENOSPC
>
> Add a perf event tracepoint link info check with a one-byte tp_name
> buffer. The query is expected to return -ENOSPC because the nested name
> buffer is too small, but it should still report the top-level link type,
> perf event type, cookie, and real tp_name length.
>
> Before the fix, bpf_link_get_info_by_fd() returned -ENOSPC but did not
> copy the top-level bpf_link_info back to userspace, leaving info.type as
> zero.
>
> Signed-off-by: Sun Jian <[email protected]>
The commit message refers to "the fix" that changed bpf_link_get_info_by_fd()
behavior, but there is no Fixes: tag. Should this carry a Fixes: tag for
the commit that first returned -ENOSPC without copying the top-level
bpf_link_info?
Fixes: f2e10bff16a0 ("bpf: Add support for BPF_OBJ_GET_INFO_BY_FD for
bpf_link")
Since the test exercises the perf-event nested fill path specifically, a
second tag for the perf_event fill_link_info support may also apply:
Fixes: 1b715e1b0ec5 ("bpf: Support ->fill_link_info for perf_event")
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/28095789600
