The bpf selftest tc_bpf failed with latest bpf-next. The following is
the command to run and the result:
$ ./test_progs -n 132
[ 40.947571] bpf_testmod: loading out-of-tree module taints kernel.
test_tc_bpf:PASS:test_tc_bpf__open_and_load 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create(BPF_TC_INGRESS) 0 nsec
test_tc_bpf:PASS:bpf_tc_hook_create invalid hook.attach_point 0 nsec
test_tc_bpf_basic:PASS:bpf_obj_get_info_by_fd 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_attach replace mode 0 nsec
test_tc_bpf_basic:PASS:bpf_tc_query 0 nsec
test_tc_bpf_basic:PASS:handle set 0 nsec
test_tc_bpf_basic:PASS:priority set 0 nsec
test_tc_bpf_basic:PASS:prog_id set 0 nsec
libbpf: Kernel error message: Failed to send filter delete notification
test_tc_bpf_basic:FAIL:bpf_tc_detach unexpected error: -3 (errno 3)
test_tc_bpf:FAIL:test_tc_internal ingress unexpected error: -3 (errno 3)
#132 tc_bpf:FAIL
The failure seems due to the commit
cfdf0d9ae75b ("rtnetlink: use nlmsg_notify() in rtnetlink_send()")
Without the above commit, rtnetlink_send() will return 0 even if
netlink_broadcast() (called by rtnetlink_send())
returns an error. The above commit makes it return
an error code if netlink_broadcast() failed.
Such a rtnetlink_send() return value change impacted the return value
for tfilter_del_notify(), in sched/cls_api.c, in the above test.
Previously return 0, now return -3 (-ESRCH), causing the test failure.
I am not sure what is the proper solution to address this.
Should we just adjust test, or kernel change is also needed?
Kumar, Yajun, could you take a look?
