No reason to rollback setting up busyloop timeout on failure.
We don't do such rollback for other things we setup in backend.
Also, look at vhost_net_init() in hw/net/vhost_net.c: we may fail
after successfully called vhost_dev_init(), and in this case we'll
just call vhost_dev_cleanup(), which doesn't rollback busyloop
timeout.

So, let's keep it simple.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Acked-by: Raphael Norwitz <raphael.s.norwitz@gmail.com>
Reviewed-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
---
 hw/virtio/vhost.c | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 8c5e434b89..2dba7d53c9 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -1621,7 +1621,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
                                                      busyloop_timeout);
             if (r < 0) {
                 error_setg_errno(errp, -r, "Failed to set busyloop timeout");
-                goto fail_busyloop;
+                goto fail;
             }
         }
     }
@@ -1661,7 +1661,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
     if (hdev->migration_blocker != NULL) {
         r = migrate_add_blocker_normal(&hdev->migration_blocker, errp);
         if (r < 0) {
-            goto fail_busyloop;
+            goto fail;
         }
     }
 
@@ -1693,17 +1693,11 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
                    " than current number of used (%d) and reserved (%d)"
                    " memory slots for memory devices.", limit, used, reserved);
         r = -EINVAL;
-        goto fail_busyloop;
+        goto fail;
     }
 
     return 0;
 
-fail_busyloop:
-    if (busyloop_timeout) {
-        while (--i >= 0) {
-            vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0);
-        }
-    }
 fail:
     hdev->nvqs = n_initialized_vqs;
     vhost_dev_cleanup(hdev);
-- 
2.48.1