On Tue, Apr 25, 2017 at 03:59:17PM -0400, Willem de Bruijn wrote:
> From: Willem de Bruijn <will...@google.com>
>
> As of tx napi, device down (`ip link set dev $dev down`) hangs unless
> tx napi is enabled. Else napi_enable is not called, so napi_disable
> will spin on test_and_set_bit NAPI_STATE_SCHED.
>
> Only call napi_disable if tx napi is enabled.
>
> Fixes: 5a719c2552ca ("virtio-net: transmit napi")
> Reported-by: Jason Wang <jasow...@redhat.com>
> Signed-off-by: Willem de Bruijn <will...@google.com>
Acked-by: Michael S. Tsirkin <m...@redhat.com>
> ---
> drivers/net/virtio_net.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 003143835766..82f1c3a73345 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -997,6 +997,12 @@ static void virtnet_napi_tx_enable(struct virtnet_info
> *vi,
> return virtnet_napi_enable(vq, napi);
> }
>
> +static void virtnet_napi_tx_disable(struct napi_struct *napi)
> +{
> + if (napi->weight)
> + napi_disable(napi);
> +}
> +
> static void refill_work(struct work_struct *work)
> {
> struct virtnet_info *vi =
> @@ -1445,7 +1451,7 @@ static int virtnet_close(struct net_device *dev)
>
> for (i = 0; i < vi->max_queue_pairs; i++) {
> napi_disable(&vi->rq[i].napi);
> - napi_disable(&vi->sq[i].napi);
> + virtnet_napi_tx_disable(&vi->sq[i].napi);
> }
>
> return 0;
> @@ -1803,7 +1809,7 @@ static void virtnet_freeze_down(struct virtio_device
> *vdev)
> if (netif_running(vi->dev)) {
> for (i = 0; i < vi->max_queue_pairs; i++) {
> napi_disable(&vi->rq[i].napi);
> - napi_disable(&vi->sq[i].napi);
> + virtnet_napi_tx_disable(&vi->sq[i].napi);
> }
> }
> }
> --
> 2.13.0.rc0.306.g87b477812d-goog
