[dpdk-stable] [PATCH 4/4] net/virtio-user: fix used ring update in cvq handling

[Tiwei Bie]

When updating used ring, the id in used element should be the
index of the first desc in the desc chain.

Fixes: f9b9d1a55775 ("net/virtio-user: add multiple queues in device emulation")
Cc: stable at dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie at intel.com>
---
 drivers/net/virtio/virtio_user/virtio_user_dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
index 89d287a74..d1157378d 100644
--- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
+++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
@@ -722,7 +722,7 @@ virtio_user_handle_cq(struct virtio_user_dev *dev, uint16_t queue_idx)
 
 		/* Update used ring */
 		uep = &vring->used->ring[avail_idx];
-		uep->id = avail_idx;
+		uep->id = desc_idx;
 		uep->len = n_descs;
 
 		vring->used->idx++;
-- 
2.17.1