Commit 79a58c06 authored by Shannon Nelson's avatar Shannon Nelson Committed by David S. Miller
Browse files

ionic: fix double use of queue-lock 



Deadlock seen in an instance where the hwstamp configuration
is changed while the driver is running:

[ 3988.736671]  schedule_preempt_disabled+0xe/0x10
[ 3988.736676]  __mutex_lock.isra.5+0x276/0x4e0
[ 3988.736683]  __mutex_lock_slowpath+0x13/0x20
[ 3988.736687]  ? __mutex_lock_slowpath+0x13/0x20
[ 3988.736692]  mutex_lock+0x2f/0x40
[ 3988.736711]  ionic_stop_queues_reconfig+0x16/0x40 [ionic]
[ 3988.736726]  ionic_reconfigure_queues+0x43e/0xc90 [ionic]
[ 3988.736738]  ionic_lif_config_hwstamp_rxq_all+0x85/0x90 [ionic]
[ 3988.736751]  ionic_lif_hwstamp_set_ts_config+0x29c/0x360 [ionic]
[ 3988.736763]  ionic_lif_hwstamp_set+0x76/0xf0 [ionic]
[ 3988.736776]  ionic_eth_ioctl+0x33/0x40 [ionic]
[ 3988.736781]  dev_ifsioc+0x12c/0x420
[ 3988.736785]  dev_ioctl+0x316/0x720

This can be demonstrated with "ptp4l -m -i <intf>"

To fix this, we pull the use of the queue_lock further up above the
callers of ionic_reconfigure_queues() and ionic_stop_queues_reconfig().

Fixes: 7ee99fc5 ("ionic: pull hwstamp queue_lock up a level")
Signed-off-by: default avatarShannon Nelson <snelson@pensando.io>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d12e1c46

drivers/net/ethernet/pensando/ionic/ionic_ethtool.c

+5 −0
Original line number Diff line number Diff line
@@ -582,7 +582,10 @@ static int ionic_set_ringparam(struct net_device *netdev, 


	qparam.ntxq_descs = ring->tx_pending;

	qparam.nrxq_descs = ring->rx_pending;



	mutex_lock(&lif->queue_lock);

	err = ionic_reconfigure_queues(lif, &qparam);

	mutex_unlock(&lif->queue_lock);

	if (err)

		netdev_info(netdev, "Ring reconfiguration failed, changes canceled: %d\n", err);
@@ -679,7 +682,9 @@ static int ionic_set_channels(struct net_device *netdev, 
		return 0;

	}



	mutex_lock(&lif->queue_lock);

	err = ionic_reconfigure_queues(lif, &qparam);

	mutex_unlock(&lif->queue_lock);

	if (err)

		netdev_info(netdev, "Queue reconfiguration failed, changes canceled: %d\n", err);

drivers/net/ethernet/pensando/ionic/ionic_lif.c

+8 −4
Original line number Diff line number Diff line
@@ -1715,7 +1715,6 @@ static int ionic_set_mac_address(struct net_device *netdev, void *sa) 
static void ionic_stop_queues_reconfig(struct ionic_lif *lif)

{

	/* Stop and clean the queues before reconfiguration */

	mutex_lock(&lif->queue_lock);

	netif_device_detach(lif->netdev);

	ionic_stop_queues(lif);

	ionic_txrx_deinit(lif);
@@ -1734,8 +1733,7 @@ static int ionic_start_queues_reconfig(struct ionic_lif *lif) 
	 * DOWN and UP to try to reset and clear the issue.

	 */

	err = ionic_txrx_init(lif);

	mutex_unlock(&lif->queue_lock);

	ionic_link_status_check_request(lif, CAN_SLEEP);

	ionic_link_status_check_request(lif, CAN_NOT_SLEEP);

	netif_device_attach(lif->netdev);



	return err;
@@ -1765,9 +1763,13 @@ static int ionic_change_mtu(struct net_device *netdev, int new_mtu) 
		return 0;

	}



	mutex_lock(&lif->queue_lock);

	ionic_stop_queues_reconfig(lif);

	netdev->mtu = new_mtu;

	return ionic_start_queues_reconfig(lif);

	err = ionic_start_queues_reconfig(lif);

	mutex_unlock(&lif->queue_lock);



	return err;

}



static void ionic_tx_timeout_work(struct work_struct *ws)
@@ -1783,8 +1785,10 @@ static void ionic_tx_timeout_work(struct work_struct *ws) 
	if (!netif_running(lif->netdev))

		return;



	mutex_lock(&lif->queue_lock);

	ionic_stop_queues_reconfig(lif);

	ionic_start_queues_reconfig(lif);

	mutex_unlock(&lif->queue_lock);

}



static void ionic_tx_timeout(struct net_device *netdev, unsigned int txqueue)