On Thu, Sep 24, 2020 at 10:18 AM Andrii Nakryiko <andriin@xxxxxx> wrote:
>
> Fix regression in libbpf, introduced by XDP link change, which causes XDP
> programs to fail to be loaded into kernel due to specified BPF_XDP
> expected_attach_type. While kernel doesn't enforce expected_attach_type for
> BPF_PROG_TYPE_XDP, some old kernels already support XDP program, but they
> don't yet recognize expected_attach_type field in bpf_attr, so setting it to
> non-zero value causes program load to fail.
>
> Luckily, libbpf already has a mechanism to deal with such cases, so just make
> expected_attach_type optional for XDP programs.
>
> Reported-by: Nikita Shirokov <tehnerd@xxxxxxxxxxx>
> Reported-by: Udip Pant <udippant@xxxxxx>
> Fixes: dc8698cac7aa ("libbpf: Add support for BPF XDP link")
> Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
Applied. Thanks
Looks like libbpf CI needs to add a few old kernels.
