From: Xu Kuohai <xukuohai@xxxxxxxxxx>
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@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230804073740.194770-4-xukuohai@xxxxxxxxxxxxxxx
Signed-off-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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)
--
2.41.0
