On Thu, Sep 24, 2020 at 10:34 AM Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> wrote: > > 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 Thanks! > > Looks like libbpf CI needs to add a few old kernels. Yeah. We have 4.9 which is very old and only a few selftests can even succeed there. Then we jump to 5.5, which is too recent to detect this issue. This issue happened on 4.15, would that be a good version to stick to? Any opinions?