Re: [PATCH net 2/2] vsock/test: Test setting SO_ZEROCOPY on accept()ed socket

[Stefano Garzarella]

On Tue, Dec 23, 2025 at 12:10:25PM +0100, Michal Luczaj wrote:
On 12/23/25 11:27, Stefano Garzarella wrote:
On Tue, Dec 23, 2025 at 10:15:29AM +0100, Michal Luczaj wrote:
Make sure setsockopt(SOL_SOCKET, SO_ZEROCOPY) on an accept()ed socket is
handled by vsock's implementation.
Signed-off-by: Michal Luczaj <m...@rbox.co>
---
tools/testing/vsock/vsock_test.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)

diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c
index 9e1250790f33..8ec8f0844e22 100644
--- a/tools/testing/vsock/vsock_test.c
+++ b/tools/testing/vsock/vsock_test.c
@@ -2192,6 +2192,34 @@ static void test_stream_nolinger_server(const struct 
test_opts *opts)
        close(fd);
}

+static void test_stream_accepted_setsockopt_client(const struct test_opts 
*opts)
+{
+       int fd;
+
+       fd = vsock_stream_connect(opts->peer_cid, opts->peer_port);
+       if (fd < 0) {
+               perror("connect");
+               exit(EXIT_FAILURE);
+       }
+
+       vsock_wait_remote_close(fd);
+       close(fd);
+}
+
+static void test_stream_accepted_setsockopt_server(const struct test_opts 
*opts)
+{
+       int fd;
+
+       fd = vsock_stream_accept(VMADDR_CID_ANY, opts->peer_port, NULL);
+       if (fd < 0) {
+               perror("accept");
+               exit(EXIT_FAILURE);
+       }
+
+       enable_so_zerocopy_check(fd);

This test is passing on my env also without the patch applied.

Is that expected?

Oh, no, definitely not. It fails for me:
36 - SOCK_STREAM accept()ed socket custom setsockopt()...36 - SOCK_STREAM
accept()ed socket custom setsockopt()...setsockopt err: Operation not
supported (95)
setsockopt SO_ZEROCOPY val 1

aaa, right, the server is failing, sorry ;-)

Reviewed-by: Stefano Garzarella <sgarz...@redhat.com>

I have no idea what's going on :)


In my suite, I'm checking the client, and if the last test fails only on 
the server, I'm missing it. I'd fix my suite, and maybe also vsock_test 
adding another sync point.

Thanks,
Stefano