From bc8acf2c8c3e43fcc192762a9f964b3e9a17748b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 2 Sep 2010 13:07:41 -0700 Subject: drivers/net: avoid some skb->ip_summed initializations fresh skbs have ip_summed set to CHECKSUM_NONE (0) We can avoid setting again skb->ip_summed to CHECKSUM_NONE in drivers. Introduce skb_checksum_none_assert() helper so that we keep this assertion documented in driver sources. Change most occurrences of : skb->ip_summed = CHECKSUM_NONE; by : skb_checksum_none_assert(skb); Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/macb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/macb.c') diff --git a/drivers/net/macb.c b/drivers/net/macb.c index ff2f158ab0b9..4297f6e8c4bc 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -407,7 +407,7 @@ static int macb_rx_frame(struct macb *bp, unsigned int first_frag, } skb_reserve(skb, RX_OFFSET); - skb->ip_summed = CHECKSUM_NONE; + skb_checksum_none_assert(skb); skb_put(skb, len); for (frag = first_frag; ; frag = NEXT_RX(frag)) { -- cgit v1.2.2 From b336369c1e1ad88495895260a9068eb18bc48b6c Mon Sep 17 00:00:00 2001 From: Joshua Hoke Date: Mon, 25 Oct 2010 01:44:22 +0000 Subject: macb: Don't re-enable interrupts while in polling mode On a busy network, the macb driver could get stuck in the interrupt handler, quickly triggering the watchdog, due to a confluence of factors: 1. macb_poll re-enables interrupts unconditionally, even when it will be called again because it exhausted its rx budget 2. macb_interrupt only disables interrupts after scheduling macb_poll, but scheduling fails when macb_poll is already scheduled because it didn't call napi_complete 3. macb_interrupt loops until the interrupt status register is clear, which will never happen in this case if the driver doesn't disable the RX interrupt Since macb_interrupt runs in interrupt context, this effectively locks up the machine, triggering the hardware watchdog. This issue was readily reproducible on a flooded network with a modified 2.6.27.48 kernel. The same problem appears to still be in the 2.6.36-rc8 driver code, so I am submitting this patch against that version. I have not tested this version of the patch except to make sure the kernel compiles. Signed-off-by: Joshua Hoke Signed-off-by: David S. Miller --- drivers/net/macb.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) (limited to 'drivers/net/macb.c') diff --git a/drivers/net/macb.c b/drivers/net/macb.c index 4297f6e8c4bc..f69e73e2191e 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -515,14 +515,15 @@ static int macb_poll(struct napi_struct *napi, int budget) (unsigned long)status, budget); work_done = macb_rx(bp, budget); - if (work_done < budget) + if (work_done < budget) { napi_complete(napi); - /* - * We've done what we can to clean the buffers. Make sure we - * get notified when new packets arrive. - */ - macb_writel(bp, IER, MACB_RX_INT_FLAGS); + /* + * We've done what we can to clean the buffers. Make sure we + * get notified when new packets arrive. + */ + macb_writel(bp, IER, MACB_RX_INT_FLAGS); + } /* TODO: Handle errors */ @@ -550,12 +551,16 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id) } if (status & MACB_RX_INT_FLAGS) { + /* + * There's no point taking any more interrupts + * until we have processed the buffers. The + * scheduling call may fail if the poll routine + * is already scheduled, so disable interrupts + * now. + */ + macb_writel(bp, IDR, MACB_RX_INT_FLAGS); + if (napi_schedule_prep(&bp->napi)) { - /* - * There's no point taking any more interrupts - * until we have processed the buffers - */ - macb_writel(bp, IDR, MACB_RX_INT_FLAGS); dev_dbg(&bp->pdev->dev, "scheduling RX softirq\n"); __napi_schedule(&bp->napi); -- cgit v1.2.2 From 915239472a5015c7667025551a73e11d6e2abee0 Mon Sep 17 00:00:00 2001 From: Jamie Iles Date: Mon, 28 Feb 2011 04:05:25 +0000 Subject: macb: don't use platform_set_drvdata() on a net_device MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 71d6429 (Driver core: convert platform_{get,set}_drvdata to static inline functions) now triggers a warning in the macb network driver: CC drivers/net/macb.o drivers/net/macb.c: In function ‘macb_mii_init’: drivers/net/macb.c:263: warning: passing argument 1 of ‘platform_set_drvdata’ from incompatible pointer type include/linux/platform_device.h:138: note: expected ‘struct platform_device *’ but argument is of type ‘struct net_device *’ Use dev_set_drvdata() on the device embedded in the net_device instead. Cc: Nicolas Ferre Signed-off-by: Jamie Iles Signed-off-by: David S. Miller --- drivers/net/macb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/macb.c') diff --git a/drivers/net/macb.c b/drivers/net/macb.c index f69e73e2191e..79ccb54ab00c 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -260,7 +260,7 @@ static int macb_mii_init(struct macb *bp) for (i = 0; i < PHY_MAX_ADDR; i++) bp->mii_bus->irq[i] = PHY_POLL; - platform_set_drvdata(bp->dev, bp->mii_bus); + dev_set_drvdata(&bp->dev->dev, bp->mii_bus); if (mdiobus_register(bp->mii_bus)) goto err_out_free_mdio_irq; -- cgit v1.2.2 From ab392d2d6d4e2e50502985eead545b44ee58802c Mon Sep 17 00:00:00 2001 From: Javier Martinez Canillas Date: Mon, 28 Mar 2011 16:27:31 +0000 Subject: drivers/net: Remove IRQF_SAMPLE_RANDOM flag from network drivers The IRQF_SAMPLE_RANDOM flag is marked as deprecated and will be removed. Every input point to the kernel's entropy pool have to better document the type of entropy source it is. drivers/char/random.c now implements a set of interfaces that can be used for devices to collect enviromental noise. IRQF_SAMPLE_RANDOM will be replaced with these add_*_randomness exported functions. Network drivers are not a good source of entropy. They use as a source of entropy essentially a remote host. Which means that the source of entropy can be potentially controlled by an attacker. Also, with heavy workloads the entropy decreases due to less hardware interrupts happening thanks to irq mitigation and NAPI. If a system relies in its network interface as a entropy source it has a false sense of security. Systems that don't have devices whose drivers are good sources of entropy, should either use a hardware random number generator or feed the kernel's entropy pool from userspace using other sources of entropy such as EGD, video_entropyd, timer_entropyd and audio-entropyd. Signed-off-by: Javier Martinez Canillas Signed-off-by: David S. Miller --- drivers/net/macb.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/net/macb.c') diff --git a/drivers/net/macb.c b/drivers/net/macb.c index 79ccb54ab00c..2cb4e792f871 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -1171,8 +1171,7 @@ static int __init macb_probe(struct platform_device *pdev) } dev->irq = platform_get_irq(pdev, 0); - err = request_irq(dev->irq, macb_interrupt, IRQF_SAMPLE_RANDOM, - dev->name, dev); + err = request_irq(dev->irq, macb_interrupt, 0, dev->name, dev); if (err) { printk(KERN_ERR "%s: Unable to request IRQ %d (error %d)\n", -- cgit v1.2.2 From b19f7f71b6fa5e0c49f65082044b8a2ff1009f00 Mon Sep 17 00:00:00 2001 From: Alexander Stein Date: Wed, 13 Apr 2011 05:03:24 +0000 Subject: macb: Add rx overrun counter Signed-off-by: Alexander Stein Signed-off-by: David S. Miller --- drivers/net/macb.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'drivers/net/macb.c') diff --git a/drivers/net/macb.c b/drivers/net/macb.c index 2cb4e792f871..629bd2649c0c 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -576,6 +576,11 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id) * add that if/when we get our hands on a full-blown MII PHY. */ + if (status & MACB_BIT(ISR_ROVR)) { + /* We missed at least one packet */ + bp->hw_stats.rx_overruns++; + } + if (status & MACB_BIT(HRESP)) { /* * TODO: Reset the hardware, and maybe move the printk @@ -1024,7 +1029,8 @@ static struct net_device_stats *macb_get_stats(struct net_device *dev) hwstat->rx_jabbers + hwstat->rx_undersize_pkts + hwstat->rx_length_mismatch); - nstat->rx_over_errors = hwstat->rx_resource_errors; + nstat->rx_over_errors = hwstat->rx_resource_errors + + hwstat->rx_overruns; nstat->rx_crc_errors = hwstat->rx_fcs_errors; nstat->rx_frame_errors = hwstat->rx_align_errors; nstat->rx_fifo_errors = hwstat->rx_overruns; -- cgit v1.2.2 From e05503ef1186ad33dfe56794407891eb1dd93ef6 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Wed, 18 May 2011 16:49:24 +0200 Subject: Haavard Skinnemoen has left Atmel Haavard's e-mail address at Atmel is no longer valid. Signed-off-by: Jean Delvare Acked-by: Havard Skinnemoen Signed-off-by: Jiri Kosina --- drivers/net/macb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/macb.c') diff --git a/drivers/net/macb.c b/drivers/net/macb.c index 79ccb54ab00c..101cf5663619 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -1351,5 +1351,5 @@ module_exit(macb_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Atmel MACB Ethernet driver"); -MODULE_AUTHOR("Haavard Skinnemoen "); +MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); MODULE_ALIAS("platform:macb"); -- cgit v1.2.2