On Mon, Jan 12, 2026 at 02:01:33AM -0800, Aditya Garg wrote:
> RSS configuration requires a valid RX indirection table. When the device
> reports a single receive queue, rndis_filter_device_add() does not
> allocate an indirection table, accepting RSS hash key updates in this
> state leads to a hang.
>
> Fix this by gating netvsc_set_rxfh() on ndc->rx_table_sz and return
> -EOPNOTSUPP when the table is absent. This aligns set_rxfh with the device
> capabilities and prevents incorrect behavior.
>
> Fixes: 962f3fee83a4 ("netvsc: add ethtool ops to get/set RSS key")
> Signed-off-by: Aditya Garg <[email protected]>
> Reviewed-by: Dipayaan Roy <[email protected]>
> ---
> drivers/net/hyperv/netvsc_drv.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
> index 3d47d749ef9f..cbd52cb79268 100644
> --- a/drivers/net/hyperv/netvsc_drv.c
> +++ b/drivers/net/hyperv/netvsc_drv.c
> @@ -1750,6 +1750,9 @@ static int netvsc_set_rxfh(struct net_device *dev,
> rxfh->hfunc != ETH_RSS_HASH_TOP)
> return -EOPNOTSUPP;
>
> + if (!ndc->rx_table_sz)
> + return -EOPNOTSUPP;
> +
> rndis_dev = ndev->extension;
> if (rxfh->indir) {
> for (i = 0; i < ndc->rx_table_sz; i++)
> --
> 2.43.0
>
LGTM.
Reviewed-by: Dipayaan Roy <[email protected]>
