On Fri, 2017-05-12 at 13:03 -0700, Stephen Hemminger wrote:
> The ndo_poll_controller function needs to schedule NAPI to pick
> up arriving packets and send completions. Otherwise no data
> will ever be received.
>
> Signed-off-by: Stephen Hemminger <sthem...@microsoft.com>
> ---
> drivers/net/hyperv/netvsc_drv.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
> index 4421a6d00375..e487ccea251c 100644
> --- a/drivers/net/hyperv/netvsc_drv.c
> +++ b/drivers/net/hyperv/netvsc_drv.c
> @@ -1158,11 +1158,20 @@ netvsc_get_rxnfc(struct net_device *dev, struct
> ethtool_rxnfc *info,
> }
>
> #ifdef CONFIG_NET_POLL_CONTROLLER
> -static void netvsc_poll_controller(struct net_device *net)
> +static void netvsc_poll_controller(struct net_device *dev)
> {
> - /* As netvsc_start_xmit() works synchronous we don't have to
> - * trigger anything here.
> - */
> + struct net_device_context *ndc = netdev_priv(dev);
> + struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
rtnl_dereference() can not possibly be used in an ndo_poll_controller()
You would certainly trigger a lockdep issue here if you compile a kernel
with enough debugging support.
CONFIG_PROVE_RCU=y
CONFIG_PROVE_RCU_REPEATEDLY=y
CONFIG_SPARSE_RCU_POINTER=y
