forcedeth: Acknowledge only interrupts that are being processed
Mike Ditto [Sat, 5 Nov 2011 14:38:21 +0000 (14:38 +0000)]
This is to avoid a race, accidentally acknowledging an interrupt that
we didn't notice and won't immediately process.  This is based solely
on code inspection; it is not known if there was an actual bug here.

Signed-off-by: David Decotigny <david.decotigny@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/nvidia/forcedeth.c

index 344cb5f..b7cf4b6 100644 (file)
@@ -3398,7 +3398,8 @@ static irqreturn_t nv_nic_irq_tx(int foo, void *data)
 
        for (i = 0;; i++) {
                events = readl(base + NvRegMSIXIrqStatus) & NVREG_IRQ_TX_ALL;
-               writel(NVREG_IRQ_TX_ALL, base + NvRegMSIXIrqStatus);
+               writel(events, base + NvRegMSIXIrqStatus);
+               netdev_dbg(dev, "tx irq events: %08x\n", events);
                if (!(events & np->irqmask))
                        break;
 
@@ -3509,7 +3510,8 @@ static irqreturn_t nv_nic_irq_rx(int foo, void *data)
 
        for (i = 0;; i++) {
                events = readl(base + NvRegMSIXIrqStatus) & NVREG_IRQ_RX_ALL;
-               writel(NVREG_IRQ_RX_ALL, base + NvRegMSIXIrqStatus);
+               writel(events, base + NvRegMSIXIrqStatus);
+               netdev_dbg(dev, "rx irq events: %08x\n", events);
                if (!(events & np->irqmask))
                        break;
 
@@ -3553,7 +3555,8 @@ static irqreturn_t nv_nic_irq_other(int foo, void *data)
 
        for (i = 0;; i++) {
                events = readl(base + NvRegMSIXIrqStatus) & NVREG_IRQ_OTHER;
-               writel(NVREG_IRQ_OTHER, base + NvRegMSIXIrqStatus);
+               writel(events, base + NvRegMSIXIrqStatus);
+               netdev_dbg(dev, "irq events: %08x\n", events);
                if (!(events & np->irqmask))
                        break;
 
@@ -3617,10 +3620,10 @@ static irqreturn_t nv_nic_irq_test(int foo, void *data)
 
        if (!(np->msi_flags & NV_MSI_X_ENABLED)) {
                events = readl(base + NvRegIrqStatus) & NVREG_IRQSTAT_MASK;
-               writel(NVREG_IRQ_TIMER, base + NvRegIrqStatus);
+               writel(events & NVREG_IRQ_TIMER, base + NvRegIrqStatus);
        } else {
                events = readl(base + NvRegMSIXIrqStatus) & NVREG_IRQSTAT_MASK;
-               writel(NVREG_IRQ_TIMER, base + NvRegMSIXIrqStatus);
+               writel(events & NVREG_IRQ_TIMER, base + NvRegMSIXIrqStatus);
        }
        pci_push(base);
        if (!(events & NVREG_IRQ_TIMER))