If error occurs while processing the virtio request we should call
'virtqueue_detach_element' to detach the element from the virtqueue
before free the elem.

Fixes: 5f503cd9f3 ("virtio-pmem: add virtio device")
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: Li Qiang <liq3ea@163.com>
---
 hw/virtio/virtio-pmem.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c
index 1e0c137497..ddb0125901 100644
--- a/hw/virtio/virtio-pmem.c
+++ b/hw/virtio/virtio-pmem.c
@@ -77,6 +77,7 @@ static void virtio_pmem_flush(VirtIODevice *vdev, VirtQueue *vq)
 
     if (req_data->elem.out_num < 1 || req_data->elem.in_num < 1) {
         virtio_error(vdev, "virtio-pmem request not proper");
+        virtqueue_detach_element(vq, (VirtQueueElement *)req_data, 0);
         g_free(req_data);
         return;
     }
-- 
2.17.1