[PATCH for-9.0 v2] vhost-vdpa: check vhost_vdpa_set_vring_ready() return value

[Stefano Garzarella]

vhost_vdpa_set_vring_ready() could already fail, but if Linux's
patch [1] will be merged, it may fail with more chance if
userspace does not activate virtqueues before DRIVER_OK when
VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK is not negotiated.

So better check its return value anyway.

[1] 
https://lore.kernel.org/virtualization/20240206145154.118044-1-sgarzare@redhat.com/T/#u

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
---
Based-on: 20240315155949.86066-1-kwolf@redhat.com

v1: https://patchew.org/QEMU/20240207092702.25242-1-sgarzare@redhat.com/
v2:
 - added acks
 - rebased on top of 
20240315155949.86066-1-kwolf@redhat.com/">https://patchew.org/QEMU/20240315155949.86066-1-kwolf@redhat.com/
---
 net/vhost-vdpa.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 85e73dd6a7..eda714d1a4 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -399,7 +399,10 @@ static int vhost_vdpa_net_data_load(NetClientState *nc)
     }
 
     for (int i = 0; i < v->dev->nvqs; ++i) {
-        vhost_vdpa_set_vring_ready(v, i + v->dev->vq_index);
+        int ret = vhost_vdpa_set_vring_ready(v, i + v->dev->vq_index);
+        if (ret < 0) {
+            return ret;
+        }
     }
     return 0;
 }
@@ -1238,7 +1241,10 @@ static int vhost_vdpa_net_cvq_load(NetClientState *nc)
 
     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
 
-    vhost_vdpa_set_vring_ready(v, v->dev->vq_index);
+    r = vhost_vdpa_set_vring_ready(v, v->dev->vq_index);
+    if (unlikely(r < 0)) {
+        return r;
+    }
 
     if (v->shadow_vqs_enabled) {
         n = VIRTIO_NET(v->dev->vdev);
@@ -1277,7 +1283,10 @@ static int vhost_vdpa_net_cvq_load(NetClientState *nc)
     }
 
     for (int i = 0; i < v->dev->vq_index; ++i) {
-        vhost_vdpa_set_vring_ready(v, i);
+        r = vhost_vdpa_set_vring_ready(v, i);
+        if (unlikely(r < 0)) {
+            return r;
+        }
     }
 
     return 0;
-- 
2.44.0