forcedeth: napi schedule lock fix

This patch fixes a potential race condition between scheduling napi and
completing napi poll. The call to netif_rx_schedule should be under
protection of the lock (as is the completion), otherwise, interrupts
could be masked off.

Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c
index e06782a..5b910cf 100644 (file)
--- a/drivers/net/forcedeth.c
+++ b/drivers/net/forcedeth.c
@@ -3405,10 +3405,10 @@ static irqreturn_t nv_nic_irq(int foo, void *data)
 
 #ifdef CONFIG_FORCEDETH_NAPI
                if (events & NVREG_IRQ_RX_ALL) {
+                       spin_lock(&np->lock);
                        netif_rx_schedule(&np->napi);
 
                        /* Disable furthur receive irq's */
-                       spin_lock(&np->lock);
                        np->irqmask &= ~NVREG_IRQ_RX_ALL;
 
                        if (np->msi_flags & NV_MSI_X_ENABLED)
@@ -3522,10 +3522,10 @@ static irqreturn_t nv_nic_irq_optimized(int foo, void *data)
 
 #ifdef CONFIG_FORCEDETH_NAPI
                if (events & NVREG_IRQ_RX_ALL) {
+                       spin_lock(&np->lock);
                        netif_rx_schedule(&np->napi);
 
                        /* Disable furthur receive irq's */
-                       spin_lock(&np->lock);
                        np->irqmask &= ~NVREG_IRQ_RX_ALL;
 
                        if (np->msi_flags & NV_MSI_X_ENABLED)