On 8/30/2023 4:10 PM, Daniel Borkmann wrote:
Hi Xu, On 8/4/23 9:37 AM, Xu Kuohai wrote:From: Xu Kuohai <xukuohai@xxxxxxxxxx> BPF CI has reported the following failure: Error: #200/79 sockmap_listen/sockmap VSOCK test_vsock_redir Error: #200/79 sockmap_listen/sockmap VSOCK test_vsock_redir ./test_progs:vsock_unix_redir_connectible:1506: egress: write: Transport endpoint is not connected vsock_unix_redir_connectible:FAIL:1506 ./test_progs:vsock_unix_redir_connectible:1506: ingress: write: Transport endpoint is not connected vsock_unix_redir_connectible:FAIL:1506 ./test_progs:vsock_unix_redir_connectible:1506: egress: write: Transport endpoint is not connected vsock_unix_redir_connectible:FAIL:1506 ./test_progs:vsock_unix_redir_connectible:1514: ingress: recv() err, errno=11 vsock_unix_redir_connectible:FAIL:1514 ./test_progs:vsock_unix_redir_connectible:1518: ingress: vsock socket map failed, a != b vsock_unix_redir_connectible:FAIL:1518 ./test_progs:vsock_unix_redir_connectible:1525: ingress: want pass count 1, have 0 It’s because the recv(... MSG_DONTWAIT) syscall in the test case is called before the queued work sk_psock_backlog() in the kernel finishes executing. So the data to be read is still queued in psock->ingress_skb and cannot be read by the user program. Therefore, the non-blocking recv() reads nothing and reports an EAGAIN error. So replace recv(... MSG_DONTWAIT) with xrecv_nonblock(), which calls select() to wait for data to be readable or timeout before calls recv(). Fixes: d61bd8c1fd02 ("selftests/bpf: add a test case for vsock sockmap") Signed-off-by: Xu Kuohai <xukuohai@xxxxxxxxxx>This is unfortunately still flaky and showing up from time to time in BPF CI, e.g. a very recent one can be found here: https://github.com/kernel-patches/bpf/actions/runs/6021475685/job/16335248421 [...] Error: #211 sockmap_listen Error: #211/79 sockmap_listen/sockmap VSOCK test_vsock_redir Error: #211/79 sockmap_listen/sockmap VSOCK test_vsock_redir ./test_progs:vsock_unix_redir_connectible:1501: egress: write: Transport endpoint is not connected vsock_unix_redir_connectible:FAIL:1501 ./test_progs:vsock_unix_redir_connectible:1501: ingress: write: Transport endpoint is not connected vsock_unix_redir_connectible:FAIL:1501 ./test_progs:vsock_unix_redir_connectible:1501: egress: write: Transport endpoint is not connected vsock_unix_redir_connectible:FAIL:1501 Could you continue to look into it to make the test more robust?
OK, it looks like I only noticed the recv failure and ignored the write failure. I'll take it a look.
Thanks a lot, Daniel
