Re: [PATCHv2 bpf-next 3/6] libbpf: Add path_fd to struct bpf_link_create_opts

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Compilation fails due to missing `path_fd` in the `uprobe_multi` UAPI struct.
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commit c73ec6f8d6c5a6bb4c8a75f70c333cac0d6d30d4
Author: Jiri Olsa <jolsa@kernel.org>

libbpf: Add path_fd to struct bpf_link_create_opts

This commit adds the path_fd field to struct bpf_link_create_opts for
uprobe_multi. It passes this new field through the kernel attribute interface.

> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> index f37e3416f61a5..96819c082c772 100644
> --- a/tools/lib/bpf/bpf.c
> +++ b/tools/lib/bpf/bpf.c
> @@ -842,6 +842,7 @@ int bpf_link_create(int prog_fd, int target_fd,
>  		attr.link_create.uprobe_multi.ref_ctr_offsets = ptr_to_u64(OPTS_GET(opts, uprobe_multi.ref_ctr_offsets, 0));
>  		attr.link_create.uprobe_multi.cookies = ptr_to_u64(OPTS_GET(opts, uprobe_multi.cookies, 0));
>  		attr.link_create.uprobe_multi.pid = OPTS_GET(opts, uprobe_multi.pid, 0);
> +		attr.link_create.uprobe_multi.path_fd = OPTS_GET(opts, uprobe_multi.path_fd, 0);

[Severity: Low]
Will this assignment cause a build failure?

Looking at the UAPI header in tools/include/uapi/linux/bpf.h, the
uprobe_multi struct inside union bpf_attr doesn't appear to have a path_fd
member:

	struct {
		__aligned_u64	path;
		__aligned_u64	offsets;
		__aligned_u64	ref_ctr_offsets;
		__aligned_u64	cookies;
		__u32		cnt;
		__u32		flags;
		__u32		pid;
	} uprobe_multi;

Should the path_fd member be added to the UAPI bpf_attr union as well?

>  		if (!OPTS_ZEROED(opts, uprobe_multi))
>  			return libbpf_err(-EINVAL);
>  		break;

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Sashiko AI review · https://sashiko.dev/#/patchset/20260610143627.804790-4-jolsa@kernel.org?part=1