Re: [Qemu-devel] [PATCH v5 3/4] vhost: fix memslot limit check

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 10 Jan 2018 00:40:12 +0800
Jay Zhou <jianjay.zhou@huawei.com> wrote:

> Since used_memslots will be updated to the actual value after
> registering memory listener for the first time, move the
> memslots limit checking to the right place.
> 
> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  hw/virtio/vhost.c | 19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index e4290ce..69b3599 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -1251,13 +1251,6 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>          goto fail;
>      }
>  
> -    if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) {
> -        error_report("vhost backend memory slots limit is less"
> -                " than current number of present memory slots");
> -        r = -1;
> -        goto fail;
> -    }
> -
>      r = hdev->vhost_ops->vhost_set_owner(hdev);
>      if (r < 0) {
>          VHOST_OPS_DEBUG("vhost_set_owner failed");
> @@ -1339,6 +1332,18 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>      hdev->memory_changed = false;
>      memory_listener_register(&hdev->memory_listener, &address_space_memory);
>      QLIST_INSERT_HEAD(&vhost_devices, hdev, entry);
> +
> +    if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) {
> +        error_report("vhost backend memory slots limit is less"
> +                " than current number of present memory slots");
> +        r = -1;
> +        if (busyloop_timeout) {
> +            goto fail_busyloop;
> +        } else {
> +            goto fail;
> +        }
> +    }
> +
>      return 0;
>  
>  fail_busyloop: