bpf selftests using iproute2 fails with:
$ ip link set dev veth0 xdp object ../bpf/xdp_dummy.o section xdp_dummy
Continuing without mounted eBPF fs. Too old kernel?
mkdir (null)/globals failed: No such file or directory
Unable to load program
This happens when the /sys/fs/bpf directory exists. In this case, mkdir
in bpf_mnt_check_target() fails with errno == EEXIST, and the function
returns -1. Thus bpf_get_work_dir() does not call bpf_mnt_fs() and the
bpffs is not mounted.
Fix this in bpf_mnt_check_target(), returning 0 when the mountpoint
exists.
Fixes: d4fcdbbec9 ("lib/bpf: Fix and simplify bpf_mnt_check_target()")
Reported-by: Mingyu Shi <mshi@redhat.com>
Reported-by: Jiri Benc <jbenc@redhat.com>
Suggested-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
2f5825cb38