drivers/net: fix tasklet misuse issue

In commit 175c0dff, drivers uses tasklet_kill to avoid put disabled tasklet
on the tasklet vec. But some of the drivers uses tasklet_init & tasklet_disable
in the driver init code, then tasklet_enable when it is opened. This makes
tasklet_enable on a killed tasklet and make ksoftirqd crazy then. Normally,
drivers should use tasklet_init/tasklet_kill on device open/remove, and use
tasklet_disable/tasklet_enable on device suspend/resume.

Reported-by: Peter Wu <lekensteyn@gmail.com>
Tested-by: Peter Wu <lekensteyn@gmail.com>
Signed-off-by: Xiaotian Feng <dannyfeng@tencent.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 6 deletions

diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index 1d04754a6637..77e6db9dcfed 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -942,6 +942,10 @@ static int axienet_open(struct net_device *ndev)
                 phy_start(lp->phy_dev);
         }
 
+        /* Enable tasklets for Axi DMA error handling */
+        tasklet_init(&lp->dma_err_tasklet, axienet_dma_err_handler,
+                     (unsigned long) lp);
+
         /* Enable interrupts for Axi DMA Tx */
         ret = request_irq(lp->tx_irq, axienet_tx_irq, 0, ndev->name, ndev);
         if (ret)
@@ -950,8 +954,7 @@ static int axienet_open(struct net_device *ndev)
         ret = request_irq(lp->rx_irq, axienet_rx_irq, 0, ndev->name, ndev);
         if (ret)
                 goto err_rx_irq;
-        /* Enable tasklets for Axi DMA error handling */
-        tasklet_enable(&lp->dma_err_tasklet);
+
         return 0;
 
 err_rx_irq:
@@ -960,6 +963,7 @@ err_tx_irq:
         if (lp->phy_dev)
                 phy_disconnect(lp->phy_dev);
         lp->phy_dev = NULL;
+        tasklet_kill(&lp->dma_err_tasklet);
         dev_err(lp->dev, "request_irq() failed\n");
         return ret;
 }
@@ -1613,10 +1617,6 @@ static int __devinit axienet_of_probe(struct platform_device *op)
                 goto err_iounmap_2;
         }
 
-        tasklet_init(&lp->dma_err_tasklet, axienet_dma_err_handler,
-                     (unsigned long) lp);
-        tasklet_disable(&lp->dma_err_tasklet);
-
         return 0;
 
 err_iounmap_2: