From patchwork Sun Nov 6 00:38:21 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [net, v5, 2/5] forcedeth: Acknowledge only interrupts that are being processed From: david decotigny X-Patchwork-Id: 123903 Message-Id: <15bc4a8d132782a42602cac8e77e8c10b6b450f9.1320539724.git.david.decotigny@google.com> To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "David S. Miller" , Ian Campbell , Eric Dumazet , Jeff Kirsher , Jiri Pirko , Joe Perches , Szymon Janc , Mike Ditto , David Decotigny Date: Sat, 5 Nov 2011 17:38:21 -0700 From: Mike Ditto 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 --- drivers/net/ethernet/nvidia/forcedeth.c | 13 ++++++++----- 1 files changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c index 344cb5f..b7cf4b6 100644 --- a/drivers/net/ethernet/nvidia/forcedeth.c +++ b/drivers/net/ethernet/nvidia/forcedeth.c @@ -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))