From: Xu Kuohai xukuohai@huawei.com
commit 90f0074cd9f9a24b7b6c4d5afffa676aee48c0e9 upstream.
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@huawei.com Link: https://lore.kernel.org/r/20230804073740.194770-4-xukuohai@huaweicloud.com Signed-off-by: Martin KaFai Lau martin.lau@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/bpf/prog_tests/sockmap_listen.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c index b4f6f3a50ae5..ba35bcc66e7e 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c @@ -1432,7 +1432,7 @@ static void vsock_unix_redir_connectible(int sock_mapfd, int verd_mapfd, if (n < 1) goto out;
- n = recv(mode == REDIR_INGRESS ? u0 : u1, &b, sizeof(b), MSG_DONTWAIT); + n = xrecv_nonblock(mode == REDIR_INGRESS ? u0 : u1, &b, sizeof(b), 0); if (n < 0) FAIL("%s: recv() err, errno=%d", log_prefix, errno); if (n == 0)