From 54309fa60b5f57b90c1842176f6045e665d21142 Mon Sep 17 00:00:00 2001 From: Frank Li Date: Tue, 7 May 2013 14:08:44 +0000 Subject: [PATCH] net: fec: fix kernel oops when plug/unplug cable many times reproduce steps 1. flood ping from other machine ping -f -s 41000 IP 2. run below script while [ 1 ]; do ethtool -s eth0 autoneg off; sleep 3;ethtool -s eth0 autoneg on; sleep 4; done; You can see oops in one hour. The reason is fec_restart clear BD but NAPI may use it. The solution is disable NAPI and stop xmit when reset BD. disable NAPI may sleep, so fec_restart can't be call in atomic context. Signed-off-by: Frank Li Reviewed-by: Lucas Stach Tested-by: Lucas Stach Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec.h | 10 ++++--- drivers/net/ethernet/freescale/fec_main.c | 44 +++++++++++++++++++++++-------- 2 files changed, 39 insertions(+), 15 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h index ceb4d43..9ce5b71 100644 --- a/drivers/net/ethernet/freescale/fec.h +++ b/drivers/net/ethernet/freescale/fec.h @@ -198,6 +198,11 @@ struct bufdesc_ex { #define FLAG_RX_CSUM_ENABLED (BD_ENET_RX_ICE | BD_ENET_RX_PCR) #define FLAG_RX_CSUM_ERROR (BD_ENET_RX_ICE | BD_ENET_RX_PCR) +struct fec_enet_delayed_work { + struct delayed_work delay_work; + bool timeout; +}; + /* The FEC buffer descriptors track the ring buffers. The rx_bd_base and * tx_bd_base always point to the base of the buffer descriptors. The * cur_rx and cur_tx point to the currently available buffer. @@ -232,9 +237,6 @@ struct fec_enet_private { /* The ring entries to be free()ed */ struct bufdesc *dirty_tx; - /* hold while accessing the HW like ringbuffer for tx/rx but not MAC */ - spinlock_t hw_lock; - struct platform_device *pdev; int opened; @@ -269,7 +271,7 @@ struct fec_enet_private { int hwts_rx_en; int hwts_tx_en; struct timer_list time_keep; - + struct fec_enet_delayed_work delay_work; }; void fec_ptp_init(struct net_device *ndev, struct platform_device *pdev); diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index e25bf83..aff0310 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -445,6 +445,13 @@ fec_restart(struct net_device *ndev, int duplex) u32 rcntl = OPT_FRAME_SIZE | 0x04; u32 ecntl = 0x2; /* ETHEREN */ + if (netif_running(ndev)) { + netif_device_detach(ndev); + napi_disable(&fep->napi); + netif_stop_queue(ndev); + netif_tx_lock(ndev); + } + /* Whack a reset. We should wait for this. */ writel(1, fep->hwp + FEC_ECNTRL); udelay(10); @@ -605,6 +612,13 @@ fec_restart(struct net_device *ndev, int duplex) /* Enable interrupts we wish to service */ writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK); + + if (netif_running(ndev)) { + netif_device_attach(ndev); + napi_enable(&fep->napi); + netif_wake_queue(ndev); + netif_tx_unlock(ndev); + } } static void @@ -644,8 +658,22 @@ fec_timeout(struct net_device *ndev) ndev->stats.tx_errors++; - fec_restart(ndev, fep->full_duplex); - netif_wake_queue(ndev); + fep->delay_work.timeout = true; + schedule_delayed_work(&(fep->delay_work.delay_work), 0); +} + +static void fec_enet_work(struct work_struct *work) +{ + struct fec_enet_private *fep = + container_of(work, + struct fec_enet_private, + delay_work.delay_work.work); + + if (fep->delay_work.timeout) { + fep->delay_work.timeout = false; + fec_restart(fep->netdev, fep->full_duplex); + netif_wake_queue(fep->netdev); + } } static void @@ -1024,16 +1052,12 @@ static void fec_enet_adjust_link(struct net_device *ndev) { struct fec_enet_private *fep = netdev_priv(ndev); struct phy_device *phy_dev = fep->phy_dev; - unsigned long flags; - int status_change = 0; - spin_lock_irqsave(&fep->hw_lock, flags); - /* Prevent a state halted on mii error */ if (fep->mii_timeout && phy_dev->state == PHY_HALTED) { phy_dev->state = PHY_RESUMING; - goto spin_unlock; + return; } if (phy_dev->link) { @@ -1061,9 +1085,6 @@ static void fec_enet_adjust_link(struct net_device *ndev) } } -spin_unlock: - spin_unlock_irqrestore(&fep->hw_lock, flags); - if (status_change) phy_print_status(phy_dev); } @@ -1732,7 +1753,6 @@ static int fec_enet_init(struct net_device *ndev) return -ENOMEM; memset(cbd_base, 0, PAGE_SIZE); - spin_lock_init(&fep->hw_lock); fep->netdev = ndev; @@ -1952,6 +1972,7 @@ fec_probe(struct platform_device *pdev) if (fep->bufdesc_ex && fep->ptp_clock) netdev_info(ndev, "registered PHC device %d\n", fep->dev_id); + INIT_DELAYED_WORK(&(fep->delay_work.delay_work), fec_enet_work); return 0; failed_register: @@ -1984,6 +2005,7 @@ fec_drv_remove(struct platform_device *pdev) struct fec_enet_private *fep = netdev_priv(ndev); int i; + cancel_delayed_work_sync(&(fep->delay_work.delay_work)); unregister_netdev(ndev); fec_enet_mii_remove(fep); del_timer_sync(&fep->time_keep); -- 2.7.4