[PATCH net v2] 8139too: fix system hang when there is a tx timeout event.

[PATCH net v2] 8139too: fix system hang when there is a tx timeout event.

[Chunhao Lin]

If tx timeout event occur, kernel will call rtl8139_tx_timeout_task() to reset
hardware. But in this function, driver does not stop tx and rx function before
reset hardware, that will cause system hang.

In this patch, add stop tx and rx function before reset hardware.

Signed-off-by: Chunhao Lin <hau@realtek.com>
---
 drivers/net/ethernet/realtek/8139too.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/realtek/8139too.c b/drivers/net/ethernet/realtek/8139too.c
index ef668d3..da4c2d8 100644
--- a/drivers/net/ethernet/realtek/8139too.c
+++ b/drivers/net/ethernet/realtek/8139too.c
@@ -1667,6 +1667,10 @@ static void rtl8139_tx_timeout_task (struct work_struct *work)
 	int i;
 	u8 tmp8;
 
+	napi_disable(&tp->napi);
+	netif_stop_queue(dev);
+	synchronize_sched();
+
 	netdev_dbg(dev, "Transmit timeout, status %02x %04x %04x media %02x\n",
 		   RTL_R8(ChipCmd), RTL_R16(IntrStatus),
 		   RTL_R16(IntrMask), RTL_R8(MediaStatus));
@@ -1696,10 +1700,10 @@ static void rtl8139_tx_timeout_task (struct work_struct *work)
 	spin_unlock_irq(&tp->lock);
 
 	/* ...and finally, reset everything */
-	if (netif_running(dev)) {
-		rtl8139_hw_start (dev);
-		netif_wake_queue (dev);
-	}
+	napi_enable(&tp->napi);
+	rtl8139_hw_start(dev);
+	netif_wake_queue(dev);
+
 	spin_unlock_bh(&tp->rx_lock);
 }
 
-- 
1.9.1

Re: [PATCH net v2] 8139too: fix system hang when there is a tx timeout event.

[David Miller]

From: Chunhao Lin <hau@realtek.com>
Date: Mon, 1 Aug 2016 13:45:30 +0800

> If tx timeout event occur, kernel will call rtl8139_tx_timeout_task() to reset
> hardware. But in this function, driver does not stop tx and rx function before
> reset hardware, that will cause system hang.
> 
> In this patch, add stop tx and rx function before reset hardware.
> 
> Signed-off-by: Chunhao Lin <hau@realtek.com>

Applied, thanks.