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 <Frank.Li@freescale.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 @@
#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 @@
/* 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 @@
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 @@
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 @@
/* 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 @@
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 @@
{
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 @@
}
}
-spin_unlock:
- spin_unlock_irqrestore(&fep->hw_lock, flags);
-
if (status_change)
phy_print_status(phy_dev);
}
@@ -1732,7 +1753,6 @@
return -ENOMEM;
memset(cbd_base, 0, PAGE_SIZE);
- spin_lock_init(&fep->hw_lock);
fep->netdev = ndev;
@@ -1952,6 +1972,7 @@
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 @@
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);