[RFC-PATCH v1 1/2] vhost: fail device start if iotlb update fails

[Prasad Pandit <ppandit@redhat.com>]

From: Prasad Pandit <pjp@fedoraproject.org>

While starting a vhost device, updating iotlb entries
via 'vhost_device_iotlb_miss' may return an error.

  qemu-kvm: vhost_device_iotlb_miss:
    700871,700871: Fail to update device iotlb

Fail device start when such an error occurs.

Signed-off-by: Prasad Pandit <pjp@fedoraproject.org>
---
 hw/virtio/vhost.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

v0:
  -> https://lore.kernel.org/all/20240711131424.181615-3-ppandit@redhat.com/

diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 06fc71746e..a70b7422b5 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -2151,7 +2151,11 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings)
          * vhost-kernel code requires for this.*/
         for (i = 0; i < hdev->nvqs; ++i) {
             struct vhost_virtqueue *vq = hdev->vqs + i;
-            vhost_device_iotlb_miss(hdev, vq->used_phys, true);
+            r = vhost_device_iotlb_miss(hdev, vq->used_phys, true);
+            if (r) {
+                VHOST_OPS_DEBUG(r, "vhost_device_iotlb_miss failed");
+                goto fail_start;
+            }
         }
     }
     vhost_start_config_intr(hdev);
--
2.46.0