4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jason Wang <jasowang@xxxxxxxxxx> [ Upstream commit 2d66f997f0545c8f7fc5cf0b49af1decb35170e7 ] We don't wakeup the virtqueue if the first byte of pending iova range is the last byte of the range we just got updated. This will lead a virtqueue to wait for IOTLB updating forever. Fixing by correct the check and wake up the virtqueue in this case. Fixes: 6b1e6cc7855b ("vhost: new device IOTLB API") Reported-by: Peter Xu <peterx@xxxxxxxxxx> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> Reviewed-by: Peter Xu <peterx@xxxxxxxxxx> Tested-by: Peter Xu <peterx@xxxxxxxxxx> Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/vhost/vhost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -905,7 +905,7 @@ static void vhost_iotlb_notify_vq(struct list_for_each_entry_safe(node, n, &d->pending_list, node) { struct vhost_iotlb_msg *vq_msg = &node->msg.iotlb; if (msg->iova <= vq_msg->iova && - msg->iova + msg->size - 1 > vq_msg->iova && + msg->iova + msg->size - 1 >= vq_msg->iova && vq_msg->type == VHOST_IOTLB_MISS) { vhost_poll_queue(&node->vq->poll); list_del(&node->node);