[dpdk-dev] [PATCH] vhost: zero_copy incompatible with client mode

[Xuan Ding <xuan.ding@intel.com>]

In server mode, virtio-user inits under the assumption that vhost-user
supports a list of features. However, this could be problematic when
in_order feature is negotiated but not supported by vhost-user when
enables dequeue_zero_copy later.

Add handling when vhost-user enables dequeue_zero_copy as client.

Signed-off-by: Xuan Ding <xuan.ding@intel.com>
---
 lib/librte_vhost/socket.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c
index 7c8012179..bb8d0d780 100644
--- a/lib/librte_vhost/socket.c
+++ b/lib/librte_vhost/socket.c
@@ -926,6 +926,12 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
 			ret = -1;
 			goto out_mutex;
 		}
+		if (!vsocket->is_server) {
+			VHOST_LOG_CONFIG(ERR,
+			"error: zero copy is incompatible with vhost client mode\n");
+			ret = -1;
+			goto out_mutex;
+		}
 		vsocket->supported_features &= ~(1ULL << VIRTIO_F_IN_ORDER);
 		vsocket->features &= ~(1ULL << VIRTIO_F_IN_ORDER);
 
-- 
2.17.1