From: Eugenio Pérez <eperezma@xxxxxxxxxx> commit 242436973831aa97e8ce19533c6c912ea8def31b upstream. Code must be resilient to enable a queue many times. At the moment the queue is resetting so it's definitely not the expected behavior. v2: set vq->ready = 0 at disable. Fixes: 2c53d0f64c06 ("vdpasim: vDPA device simulator") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx> Message-Id: <20220519145919.772896-1-eperezma@xxxxxxxxxx> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/vdpa/vdpa_sim/vdpa_sim.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -473,11 +473,14 @@ static void vdpasim_set_vq_ready(struct { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; + bool old_ready; spin_lock(&vdpasim->lock); + old_ready = vq->ready; vq->ready = ready; - if (vq->ready) + if (vq->ready && !old_ready) { vdpasim_queue_ready(vdpasim, idx); + } spin_unlock(&vdpasim->lock); }