net: korina: Fix NAPI versus resources freeing
authorFlorian Fainelli <f.fainelli@gmail.com>
Sat, 24 Dec 2016 03:56:56 +0000 (19:56 -0800)
committerDavid S. Miller <davem@davemloft.net>
Mon, 26 Dec 2016 16:26:16 +0000 (11:26 -0500)
Commit beb0babfb77e ("korina: disable napi on close and restart")
introduced calls to napi_disable() that were missing before,
unfortunately this leaves a small window during which NAPI has a chance
to run, yet we just freed resources since korina_free_ring() has been
called:

Fix this by disabling NAPI first then freeing resource, and make sure
that we also cancel the restart task before doing the resource freeing.

Fixes: beb0babfb77e ("korina: disable napi on close and restart")
Reported-by: Alexandros C. Couloumbis <alex@ozo.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/korina.c

index cbeea915f02699696072d1da77c724588e5c3b0e..8037426ec50fa4337cd4e0cc40dabb71082fb487 100644 (file)
@@ -900,10 +900,10 @@ static void korina_restart_task(struct work_struct *work)
                                DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR,
                                &lp->rx_dma_regs->dmasm);
 
-       korina_free_ring(dev);
-
        napi_disable(&lp->napi);
 
+       korina_free_ring(dev);
+
        if (korina_init(dev) < 0) {
                printk(KERN_ERR "%s: cannot restart device\n", dev->name);
                return;
@@ -1064,12 +1064,12 @@ static int korina_close(struct net_device *dev)
        tmp = tmp | DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR;
        writel(tmp, &lp->rx_dma_regs->dmasm);
 
-       korina_free_ring(dev);
-
        napi_disable(&lp->napi);
 
        cancel_work_sync(&lp->restart_task);
 
+       korina_free_ring(dev);
+
        free_irq(lp->rx_irq, dev);
        free_irq(lp->tx_irq, dev);
        free_irq(lp->ovr_irq, dev);