From: Matteo Croce <mcroce@xxxxxxxxxx> [ Upstream commit 230bd958c2c846ee292aa38bc6b006296c24ca01 ] The MTU change code can call napi_disable() with the device already down, leading to a deadlock. Also, lot of code is duplicated unnecessarily. Rework mvpp2_change_mtu() to avoid the deadlock and remove duplicated code. Fixes: 3f518509dedc ("ethernet: Add new driver for Marvell Armada 375 network unit") Signed-off-by: Matteo Croce <mcroce@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 41 +++++++----------------- 1 file changed, 13 insertions(+), 28 deletions(-) --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c @@ -3609,6 +3609,7 @@ static int mvpp2_set_mac_address(struct static int mvpp2_change_mtu(struct net_device *dev, int mtu) { struct mvpp2_port *port = netdev_priv(dev); + bool running = netif_running(dev); int err; if (!IS_ALIGNED(MVPP2_RX_PKT_SIZE(mtu), 8)) { @@ -3617,40 +3618,24 @@ static int mvpp2_change_mtu(struct net_d mtu = ALIGN(MVPP2_RX_PKT_SIZE(mtu), 8); } - if (!netif_running(dev)) { - err = mvpp2_bm_update_mtu(dev, mtu); - if (!err) { - port->pkt_size = MVPP2_RX_PKT_SIZE(mtu); - return 0; - } + if (running) + mvpp2_stop_dev(port); + err = mvpp2_bm_update_mtu(dev, mtu); + if (err) { + netdev_err(dev, "failed to change MTU\n"); /* Reconfigure BM to the original MTU */ - err = mvpp2_bm_update_mtu(dev, dev->mtu); - if (err) - goto log_error; + mvpp2_bm_update_mtu(dev, dev->mtu); + } else { + port->pkt_size = MVPP2_RX_PKT_SIZE(mtu); } - mvpp2_stop_dev(port); - - err = mvpp2_bm_update_mtu(dev, mtu); - if (!err) { - port->pkt_size = MVPP2_RX_PKT_SIZE(mtu); - goto out_start; + if (running) { + mvpp2_start_dev(port); + mvpp2_egress_enable(port); + mvpp2_ingress_enable(port); } - /* Reconfigure BM to the original MTU */ - err = mvpp2_bm_update_mtu(dev, dev->mtu); - if (err) - goto log_error; - -out_start: - mvpp2_start_dev(port); - mvpp2_egress_enable(port); - mvpp2_ingress_enable(port); - - return 0; -log_error: - netdev_err(dev, "failed to change MTU\n"); return err; }