Commit 5b1d9c17 authored by Hayes Wang's avatar Hayes Wang Committed by David S. Miller
Browse files

r8152: avoid to call napi_disable twice 



Call napi_disable() twice would cause dead lock. There are three situations
may result in the issue.

1. rtl8152_pre_reset() and set_carrier() are run at the same time.
2. Call rtl8152_set_tunable() after rtl8152_close().
3. Call rtl8152_set_ringparam() after rtl8152_close().

For #1, use the same solution as commit 84811412 ("r8152: Re-order
napi_disable in rtl8152_close"). For #2 and #3, add checking the flag
of IFF_UP and using napi_disable/napi_enable during mutex.

Signed-off-by: default avatarHayes Wang <hayeswang@realtek.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 06829937

drivers/net/usb/r8152.c

+20 −8
Original line number Diff line number Diff line
@@ -4552,10 +4552,10 @@ static int rtl8152_pre_reset(struct usb_interface *intf) 


	netif_stop_queue(netdev);

	tasklet_disable(&tp->tx_tl);

	napi_disable(&tp->napi);

	clear_bit(WORK_ENABLE, &tp->flags);

	usb_kill_urb(tp->intr_urb);

	cancel_delayed_work_sync(&tp->schedule);

	napi_disable(&tp->napi);

	if (netif_carrier_ok(netdev)) {

		mutex_lock(&tp->control);

		tp->rtl_ops.disable(tp);
@@ -4673,7 +4673,7 @@ static int rtl8152_system_resume(struct r8152 *tp) 


	netif_device_attach(netdev);



	if (netif_running(netdev) && netdev->flags & IFF_UP) {

	if (netif_running(netdev) && (netdev->flags & IFF_UP)) {

		tp->rtl_ops.up(tp);

		netif_carrier_off(netdev);

		set_bit(WORK_ENABLE, &tp->flags);
@@ -5244,9 +5244,15 @@ static int rtl8152_set_tunable(struct net_device *netdev, 
		}



		if (tp->rx_copybreak != val) {

			if (netdev->flags & IFF_UP) {

				mutex_lock(&tp->control);

				napi_disable(&tp->napi);

				tp->rx_copybreak = val;

				napi_enable(&tp->napi);

				mutex_unlock(&tp->control);

			} else {

				tp->rx_copybreak = val;

			}

		}

		break;

	default:
@@ -5274,9 +5280,15 @@ static int rtl8152_set_ringparam(struct net_device *netdev, 
		return -EINVAL;



	if (tp->rx_pending != ring->rx_pending) {

		if (netdev->flags & IFF_UP) {

			mutex_lock(&tp->control);

			napi_disable(&tp->napi);

			tp->rx_pending = ring->rx_pending;

			napi_enable(&tp->napi);

			mutex_unlock(&tp->control);

		} else {

			tp->rx_pending = ring->rx_pending;

		}

	}



	return 0;

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