[PATCH v2 0/7] network driver fixes

[PATCH v2 0/7] network driver fixes

[Arnd Bergmann]

This is an updated series of fixes for the network device drivers
that showed warnings in ARM randconfig.

Changes since v1 are:

dropped "net: macb: avoid uninitialized variables", already fixed in net-next

dropped "net: fddi/defxx: avoid warning about uninitialized variable
	use", already fixed in net-next

added missing barriers in "net: moxart: use correct accessors for
	DMA memory"

clarified "net: bgmac: clarify CONFIG_BCMA dependency" changelog


Arnd Bergmann (7):
  net: moxart: use correct accessors for DMA memory
  net: davinci_cpdma: use dma_addr_t for DMA address
  net: hp100: remove unnecessary #ifdefs
  net: bgmac: clarify CONFIG_BCMA dependency
  net: vxge: avoid unused function warnings
  net: nb8800: avoid uninitialized variable warning
  net: tg3: avoid uninitialized variable warning

 drivers/net/ethernet/aurora/nb8800.c           |  4 +--
 drivers/net/ethernet/broadcom/Kconfig          |  5 ++-
 drivers/net/ethernet/broadcom/tg3.c            |  2 +-
 drivers/net/ethernet/hp/hp100.c                | 18 ----------
 drivers/net/ethernet/moxa/moxart_ether.c       | 46 +++++++++++++++++---------
 drivers/net/ethernet/moxa/moxart_ether.h       |  4 +--
 drivers/net/ethernet/neterion/vxge/vxge-main.c | 31 +++++++----------
 drivers/net/ethernet/ti/davinci_cpdma.c        | 12 +++----
 8 files changed, 57 insertions(+), 65 deletions(-)

-- 
2.7.0

[PATCH v2 1/7] net: moxart: use correct accessors for DMA memory

[Arnd Bergmann]

The moxart ethernet driver confuses coherent DMA buffers with
MMIO registers.

moxart_ether.c: In function 'moxart_mac_setup_desc_ring':
moxart_ether.c:146:428: error: passing argument 1 of '__fswab32' makes integer from pointer without a cast [-Werror=int-conversion]
moxart_ether.c:74:39: warning: incorrect type in argument 3 (different address spaces)
moxart_ether.c:74:39:    expected void *cpu_addr
moxart_ether.c:74:39:    got void [noderef] <asn:2>*tx_desc_base

This leaves the basic logic alone and uses normal pointers for
the virtual address of the descriptor. As we cannot use readl/writel
to access them, we also introduce our own moxart_desc_read
moxart_desc_write helpers that perform the same endianess swap
as the original code, but without the address space conversion.

The barriers are made explicit here where needed: Even in the worst-case
scenario, we just have to use a rmb() after checking ownership so
we don't read any input data before we are sure it is value, and we
use wmb() before transferring ownership back to the device.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/ethernet/moxa/moxart_ether.c | 46 +++++++++++++++++++++-----------
 drivers/net/ethernet/moxa/moxart_ether.h |  4 +--
 2 files changed, 32 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/moxa/moxart_ether.c b/drivers/net/ethernet/moxa/moxart_ether.c
index a10c928bbd6b..00cfd95ca59d 100644
--- a/drivers/net/ethernet/moxa/moxart_ether.c
+++ b/drivers/net/ethernet/moxa/moxart_ether.c
@@ -28,6 +28,16 @@
 
 #include "moxart_ether.h"
 
+static inline void moxart_desc_write(u32 data, u32 *desc)
+{
+	*desc = cpu_to_le32(data);
+}
+
+static inline u32 moxart_desc_read(u32 *desc)
+{
+	return le32_to_cpu(*desc);
+}
+
 static inline void moxart_emac_write(struct net_device *ndev,
 				     unsigned int reg, unsigned long value)
 {
@@ -112,7 +122,7 @@ static void moxart_mac_enable(struct net_device *ndev)
 static void moxart_mac_setup_desc_ring(struct net_device *ndev)
 {
 	struct moxart_mac_priv_t *priv = netdev_priv(ndev);
-	void __iomem *desc;
+	void *desc;
 	int i;
 
 	for (i = 0; i < TX_DESC_NUM; i++) {
@@ -121,7 +131,7 @@ static void moxart_mac_setup_desc_ring(struct net_device *ndev)
 
 		priv->tx_buf[i] = priv->tx_buf_base + priv->tx_buf_size * i;
 	}
-	writel(TX_DESC1_END, desc + TX_REG_OFFSET_DESC1);
+	moxart_desc_write(TX_DESC1_END, desc + TX_REG_OFFSET_DESC1);
 
 	priv->tx_head = 0;
 	priv->tx_tail = 0;
@@ -129,8 +139,8 @@ static void moxart_mac_setup_desc_ring(struct net_device *ndev)
 	for (i = 0; i < RX_DESC_NUM; i++) {
 		desc = priv->rx_desc_base + i * RX_REG_DESC_SIZE;
 		memset(desc, 0, RX_REG_DESC_SIZE);
-		writel(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
-		writel(RX_BUF_SIZE & RX_DESC1_BUF_SIZE_MASK,
+		moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
+		moxart_desc_write(RX_BUF_SIZE & RX_DESC1_BUF_SIZE_MASK,
 		       desc + RX_REG_OFFSET_DESC1);
 
 		priv->rx_buf[i] = priv->rx_buf_base + priv->rx_buf_size * i;
@@ -141,12 +151,12 @@ static void moxart_mac_setup_desc_ring(struct net_device *ndev)
 		if (dma_mapping_error(&ndev->dev, priv->rx_mapping[i]))
 			netdev_err(ndev, "DMA mapping error\n");
 
-		writel(priv->rx_mapping[i],
+		moxart_desc_write(priv->rx_mapping[i],
 		       desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_PHYS);
-		writel(priv->rx_buf[i],
+		moxart_desc_write((uintptr_t)priv->rx_buf[i],
 		       desc + RX_REG_OFFSET_DESC2 + RX_DESC2_ADDRESS_VIRT);
 	}
-	writel(RX_DESC1_END, desc + RX_REG_OFFSET_DESC1);
+	moxart_desc_write(RX_DESC1_END, desc + RX_REG_OFFSET_DESC1);
 
 	priv->rx_head = 0;
 
@@ -201,14 +211,15 @@ static int moxart_rx_poll(struct napi_struct *napi, int budget)
 						      napi);
 	struct net_device *ndev = priv->ndev;
 	struct sk_buff *skb;
-	void __iomem *desc;
+	void *desc;
 	unsigned int desc0, len;
 	int rx_head = priv->rx_head;
 	int rx = 0;
 
 	while (rx < budget) {
 		desc = priv->rx_desc_base + (RX_REG_DESC_SIZE * rx_head);
-		desc0 = readl(desc + RX_REG_OFFSET_DESC0);
+		desc0 = moxart_desc_read(desc + RX_REG_OFFSET_DESC0);
+		rmb(); /* ensure desc0 is up to date */
 
 		if (desc0 & RX_DESC0_DMA_OWN)
 			break;
@@ -250,7 +261,8 @@ static int moxart_rx_poll(struct napi_struct *napi, int budget)
 			priv->stats.multicast++;
 
 rx_next:
-		writel(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
+		wmb(); /* prevent setting ownership back too early */
+		moxart_desc_write(RX_DESC0_DMA_OWN, desc + RX_REG_OFFSET_DESC0);
 
 		rx_head = RX_NEXT(rx_head);
 		priv->rx_head = rx_head;
@@ -310,7 +322,7 @@ static irqreturn_t moxart_mac_interrupt(int irq, void *dev_id)
 static int moxart_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 {
 	struct moxart_mac_priv_t *priv = netdev_priv(ndev);
-	void __iomem *desc;
+	void *desc;
 	unsigned int len;
 	unsigned int tx_head = priv->tx_head;
 	u32 txdes1;
@@ -319,11 +331,12 @@ static int moxart_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 	desc = priv->tx_desc_base + (TX_REG_DESC_SIZE * tx_head);
 
 	spin_lock_irq(&priv->txlock);
-	if (readl(desc + TX_REG_OFFSET_DESC0) & TX_DESC0_DMA_OWN) {
+	if (moxart_desc_read(desc + TX_REG_OFFSET_DESC0) & TX_DESC0_DMA_OWN) {
 		net_dbg_ratelimited("no TX space for packet\n");
 		priv->stats.tx_dropped++;
 		goto out_unlock;
 	}
+	rmb(); /* ensure data is only read that had TX_DESC0_DMA_OWN cleared */
 
 	len = skb->len > TX_BUF_SIZE ? TX_BUF_SIZE : skb->len;
 
@@ -337,9 +350,9 @@ static int moxart_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 	priv->tx_len[tx_head] = len;
 	priv->tx_skb[tx_head] = skb;
 
-	writel(priv->tx_mapping[tx_head],
+	moxart_desc_write(priv->tx_mapping[tx_head],
 	       desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_PHYS);
-	writel(skb->data,
+	moxart_desc_write((uintptr_t)skb->data,
 	       desc + TX_REG_OFFSET_DESC2 + TX_DESC2_ADDRESS_VIRT);
 
 	if (skb->len < ETH_ZLEN) {
@@ -354,8 +367,9 @@ static int moxart_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 	txdes1 = TX_DESC1_LTS | TX_DESC1_FTS | (len & TX_DESC1_BUF_SIZE_MASK);
 	if (tx_head == TX_DESC_NUM_MASK)
 		txdes1 |= TX_DESC1_END;
-	writel(txdes1, desc + TX_REG_OFFSET_DESC1);
-	writel(TX_DESC0_DMA_OWN, desc + TX_REG_OFFSET_DESC0);
+	moxart_desc_write(txdes1, desc + TX_REG_OFFSET_DESC1);
+	wmb(); /* flush descriptor before transferring ownership */
+	moxart_desc_write(TX_DESC0_DMA_OWN, desc + TX_REG_OFFSET_DESC0);
 
 	/* start to send packet */
 	writel(0xffffffff, priv->base + REG_TX_POLL_DEMAND);
diff --git a/drivers/net/ethernet/moxa/moxart_ether.h b/drivers/net/ethernet/moxa/moxart_ether.h
index 2be9280d608c..93a9563ac7c6 100644
--- a/drivers/net/ethernet/moxa/moxart_ether.h
+++ b/drivers/net/ethernet/moxa/moxart_ether.h
@@ -300,7 +300,7 @@ struct moxart_mac_priv_t {
 
 	dma_addr_t rx_base;
 	dma_addr_t rx_mapping[RX_DESC_NUM];
-	void __iomem *rx_desc_base;
+	void *rx_desc_base;
 	unsigned char *rx_buf_base;
 	unsigned char *rx_buf[RX_DESC_NUM];
 	unsigned int rx_head;
@@ -308,7 +308,7 @@ struct moxart_mac_priv_t {
 
 	dma_addr_t tx_base;
 	dma_addr_t tx_mapping[TX_DESC_NUM];
-	void __iomem *tx_desc_base;
+	void *tx_desc_base;
 	unsigned char *tx_buf_base;
 	unsigned char *tx_buf[RX_DESC_NUM];
 	unsigned int tx_head;
-- 
2.7.0

[PATCH v2 2/7] net: davinci_cpdma: use dma_addr_t for DMA address

[Arnd Bergmann]

The davinci_cpdma mixes up physical addresses as seen from the CPU
and DMA addresses as seen from a DMA master, since it can operate
on both normal memory or an on-chip buffer. If dma_addr_t is
different from phys_addr_t, this means we get a compile-time warning
about the type mismatch:

ethernet/ti/davinci_cpdma.c: In function 'cpdma_desc_pool_create':
ethernet/ti/davinci_cpdma.c:182:48: error: passing argument 3 of 'dma_alloc_coherent' from incompatible pointer type [-Werror=incompatible-pointer-types]
   pool->cpumap = dma_alloc_coherent(dev, size, &pool->phys,
In file included from ethernet/ti/davinci_cpdma.c:21:0:
dma-mapping.h:398:21: note: expected 'dma_addr_t * {aka long long unsigned int *}' but argument is of type 'phys_addr_t * {aka unsigned int *}'
 static inline void *dma_alloc_coherent(struct device *dev, size_t size,

This slightly restructures the code so the address we use for
mapping RAM into a DMA address is always a dma_addr_t, avoiding
the warning. The code is correct even if both types are 32-bit
because the DMA master in this device only supports 32-bit addressing
anyway, independent of the types that are used.

We still assign this value to pool->phys, and that is wrong if
the driver is ever used with an IOMMU, but that value appears to
be never used, so there is no problem really. I've added a couple
of comments about where we do things that are slightly violating
the API.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/ethernet/ti/davinci_cpdma.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/ti/davinci_cpdma.c b/drivers/net/ethernet/ti/davinci_cpdma.c
index 657b65bf5cac..18bf3a8fdc50 100644
--- a/drivers/net/ethernet/ti/davinci_cpdma.c
+++ b/drivers/net/ethernet/ti/davinci_cpdma.c
@@ -82,7 +82,7 @@ struct cpdma_desc {
 
 struct cpdma_desc_pool {
 	phys_addr_t		phys;
-	u32			hw_addr;
+	dma_addr_t		hw_addr;
 	void __iomem		*iomap;		/* ioremap map */
 	void			*cpumap;	/* dma_alloc map */
 	int			desc_size, mem_size;
@@ -152,7 +152,7 @@ struct cpdma_chan {
  * abstract out these details
  */
 static struct cpdma_desc_pool *
-cpdma_desc_pool_create(struct device *dev, u32 phys, u32 hw_addr,
+cpdma_desc_pool_create(struct device *dev, u32 phys, dma_addr_t hw_addr,
 				int size, int align)
 {
 	int bitmap_size;
@@ -176,13 +176,13 @@ cpdma_desc_pool_create(struct device *dev, u32 phys, u32 hw_addr,
 
 	if (phys) {
 		pool->phys  = phys;
-		pool->iomap = ioremap(phys, size);
+		pool->iomap = ioremap(phys, size); /* should be memremap? */
 		pool->hw_addr = hw_addr;
 	} else {
-		pool->cpumap = dma_alloc_coherent(dev, size, &pool->phys,
+		pool->cpumap = dma_alloc_coherent(dev, size, &pool->hw_addr,
 						  GFP_KERNEL);
-		pool->iomap = pool->cpumap;
-		pool->hw_addr = pool->phys;
+		pool->iomap = (void __iomem __force *)pool->cpumap;
+		pool->phys = pool->hw_addr; /* assumes no IOMMU, don't use this value */
 	}
 
 	if (pool->iomap)
-- 
2.7.0

[PATCH v2 3/7] net: hp100: remove unnecessary #ifdefs

[Arnd Bergmann]

Building the hp100 ethernet driver causes warnings when both the PCI
and EISA drivers are disabled:

ethernet/hp/hp100.c: In function 'hp100_module_init':
ethernet/hp/hp100.c:3047:2: warning: label 'out3' defined but not used [-Wunused-label]
ethernet/hp/hp100.c: At top level:
ethernet/hp/hp100.c:2828:13: warning: 'cleanup_dev' defined but not used [-Wunused-function]

We can easily avoid the warnings and make the driver look slightly
nicer by removing the #ifdefs that check for the CONFIG_PCI and
CONFIG_EISA, as all the registration functions are designed to
have no effect when the buses are disabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/ethernet/hp/hp100.c | 18 ------------------
 1 file changed, 18 deletions(-)

diff --git a/drivers/net/ethernet/hp/hp100.c b/drivers/net/ethernet/hp/hp100.c
index 1d5c3e16d8f4..3daf2d4a7ca0 100644
--- a/drivers/net/ethernet/hp/hp100.c
+++ b/drivers/net/ethernet/hp/hp100.c
@@ -194,7 +194,6 @@ static const char *hp100_isa_tbl[] = {
 };
 #endif
 
-#ifdef CONFIG_EISA
 static struct eisa_device_id hp100_eisa_tbl[] = {
 	{ "HWPF180" }, /* HP J2577 rev A */
 	{ "HWP1920" }, /* HP 27248B */
@@ -205,9 +204,7 @@ static struct eisa_device_id hp100_eisa_tbl[] = {
 	{ "" }	       /* Mandatory final entry ! */
 };
 MODULE_DEVICE_TABLE(eisa, hp100_eisa_tbl);
-#endif
 
-#ifdef CONFIG_PCI
 static const struct pci_device_id hp100_pci_tbl[] = {
 	{PCI_VENDOR_ID_HP, PCI_DEVICE_ID_HP_J2585A, PCI_ANY_ID, PCI_ANY_ID,},
 	{PCI_VENDOR_ID_HP, PCI_DEVICE_ID_HP_J2585B, PCI_ANY_ID, PCI_ANY_ID,},
@@ -219,7 +216,6 @@ static const struct pci_device_id hp100_pci_tbl[] = {
 	{}			/* Terminating entry */
 };
 MODULE_DEVICE_TABLE(pci, hp100_pci_tbl);
-#endif
 
 static int hp100_rx_ratio = HP100_DEFAULT_RX_RATIO;
 static int hp100_priority_tx = HP100_DEFAULT_PRIORITY_TX;
@@ -2842,7 +2838,6 @@ static void cleanup_dev(struct net_device *d)
 	free_netdev(d);
 }
 
-#ifdef CONFIG_EISA
 static int hp100_eisa_probe(struct device *gendev)
 {
 	struct net_device *dev = alloc_etherdev(sizeof(struct hp100_private));
@@ -2884,9 +2879,7 @@ static struct eisa_driver hp100_eisa_driver = {
 		.remove  = hp100_eisa_remove,
         }
 };
-#endif
 
-#ifdef CONFIG_PCI
 static int hp100_pci_probe(struct pci_dev *pdev,
 			   const struct pci_device_id *ent)
 {
@@ -2955,7 +2948,6 @@ static struct pci_driver hp100_pci_driver = {
 	.probe		= hp100_pci_probe,
 	.remove		= hp100_pci_remove,
 };
-#endif
 
 /*
  *  module section
@@ -3032,23 +3024,17 @@ static int __init hp100_module_init(void)
 	err = hp100_isa_init();
 	if (err && err != -ENODEV)
 		goto out;
-#ifdef CONFIG_EISA
 	err = eisa_driver_register(&hp100_eisa_driver);
 	if (err && err != -ENODEV)
 		goto out2;
-#endif
-#ifdef CONFIG_PCI
 	err = pci_register_driver(&hp100_pci_driver);
 	if (err && err != -ENODEV)
 		goto out3;
-#endif
  out:
 	return err;
  out3:
-#ifdef CONFIG_EISA
 	eisa_driver_unregister (&hp100_eisa_driver);
  out2:
-#endif
 	hp100_isa_cleanup();
 	goto out;
 }
@@ -3057,12 +3043,8 @@ static int __init hp100_module_init(void)
 static void __exit hp100_module_exit(void)
 {
 	hp100_isa_cleanup();
-#ifdef CONFIG_EISA
 	eisa_driver_unregister (&hp100_eisa_driver);
-#endif
-#ifdef CONFIG_PCI
 	pci_unregister_driver (&hp100_pci_driver);
-#endif
 }
 
 module_init(hp100_module_init)
-- 
2.7.0

[PATCH v2 4/7] net: bgmac: clarify CONFIG_BCMA dependency

[Arnd Bergmann]

The bgmac driver depends on BCMA_HOST_SOC, which is only used
when CONFIG_BCMA is enabled. However, it is a bool option and can
be set when CONFIG_BCMA=m, and then bgmac can be built-in, leading
to an obvious link error:

drivers/built-in.o: In function `bgmac_init':
:(.init.text+0x7f2c): undefined reference to `__bcma_driver_register'
drivers/built-in.o: In function `bgmac_exit':
:(.exit.text+0x110a): undefined reference to `bcma_driver_unregister'

To avoid this case, we need to depend on both BCMA and BCMA_SOC,
as this patch does. I'm also trying to make the dependency more
readable by splitting it into three lines, and adding a COMPILE_TEST
alternative so we can test-build it in all configurations that
support BCMA.

The added dependency on FIXED_PHY addresses a related issue where
we cannot call fixed_phy_register() when CONFIG_FIXED_PHY=m and
CONFIG_BGMAC=y.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/ethernet/broadcom/Kconfig | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/Kconfig b/drivers/net/ethernet/broadcom/Kconfig
index 8550df189ceb..19f7cd02e085 100644
--- a/drivers/net/ethernet/broadcom/Kconfig
+++ b/drivers/net/ethernet/broadcom/Kconfig
@@ -151,8 +151,11 @@ config BNX2X_VXLAN
 
 config BGMAC
 	tristate "BCMA bus GBit core support"
-	depends on BCMA_HOST_SOC && HAS_DMA && (BCM47XX || ARCH_BCM_5301X)
+	depends on BCMA && BCMA_HOST_SOC
+	depends on HAS_DMA
+	depends on BCM47XX || ARCH_BCM_5301X || COMPILE_TEST
 	select PHYLIB
+	select FIXED_PHY
 	---help---
 	  This driver supports GBit MAC and BCM4706 GBit MAC cores on BCMA bus.
 	  They can be found on BCM47xx SoCs and provide gigabit ethernet.
-- 
2.7.0

[PATCH v2 5/7] net: vxge: avoid unused function warnings

[Arnd Bergmann]

When CONFIG_PCI_MSI is disabled, we get warnings about unused functions
in the vxge driver:

drivers/net/ethernet/neterion/vxge/vxge-main.c:2121:13: warning: 'adaptive_coalesce_tx_interrupts' defined but not used [-Wunused-function]
drivers/net/ethernet/neterion/vxge/vxge-main.c:2149:13: warning: 'adaptive_coalesce_rx_interrupts' defined but not used [-Wunused-function]

We could add another #ifdef here, but it's nicer to avoid those warnings
for good by converting the existing #ifdef to if(IS_ENABLED()), which has
the same effect but provides better compile-time coverage in general,
and lets the compiler understand better when the function is intentionally
unused.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/ethernet/neterion/vxge/vxge-main.c | 31 ++++++++++----------------
 1 file changed, 12 insertions(+), 19 deletions(-)

diff --git a/drivers/net/ethernet/neterion/vxge/vxge-main.c b/drivers/net/ethernet/neterion/vxge/vxge-main.c
index 50d5604833ed..e0993eba5df3 100644
--- a/drivers/net/ethernet/neterion/vxge/vxge-main.c
+++ b/drivers/net/ethernet/neterion/vxge/vxge-main.c
@@ -2223,8 +2223,6 @@ static irqreturn_t vxge_isr_napi(int irq, void *dev_id)
 	return IRQ_NONE;
 }
 
-#ifdef CONFIG_PCI_MSI
-
 static irqreturn_t vxge_tx_msix_handle(int irq, void *dev_id)
 {
 	struct vxge_fifo *fifo = (struct vxge_fifo *)dev_id;
@@ -2442,16 +2440,13 @@ static void vxge_rem_msix_isr(struct vxgedev *vdev)
 	if (vdev->config.intr_type == MSI_X)
 		pci_disable_msix(vdev->pdev);
 }
-#endif
 
 static void vxge_rem_isr(struct vxgedev *vdev)
 {
-#ifdef CONFIG_PCI_MSI
-	if (vdev->config.intr_type == MSI_X) {
+	if (IS_ENABLED(CONFIG_PCI_MSI) &&
+	    vdev->config.intr_type == MSI_X) {
 		vxge_rem_msix_isr(vdev);
-	} else
-#endif
-	if (vdev->config.intr_type == INTA) {
+	} else if (vdev->config.intr_type == INTA) {
 			synchronize_irq(vdev->pdev->irq);
 			free_irq(vdev->pdev->irq, vdev);
 	}
@@ -2460,11 +2455,10 @@ static void vxge_rem_isr(struct vxgedev *vdev)
 static int vxge_add_isr(struct vxgedev *vdev)
 {
 	int ret = 0;
-#ifdef CONFIG_PCI_MSI
 	int vp_idx = 0, intr_idx = 0, intr_cnt = 0, msix_idx = 0, irq_req = 0;
 	int pci_fun = PCI_FUNC(vdev->pdev->devfn);
 
-	if (vdev->config.intr_type == MSI_X)
+	if (IS_ENABLED(CONFIG_PCI_MSI) && vdev->config.intr_type == MSI_X)
 		ret = vxge_enable_msix(vdev);
 
 	if (ret) {
@@ -2475,7 +2469,7 @@ static int vxge_add_isr(struct vxgedev *vdev)
 		vdev->config.intr_type = INTA;
 	}
 
-	if (vdev->config.intr_type == MSI_X) {
+	if (IS_ENABLED(CONFIG_PCI_MSI) && vdev->config.intr_type == MSI_X) {
 		for (intr_idx = 0;
 		     intr_idx < (vdev->no_of_vpath *
 			VXGE_HW_VPATH_MSIX_ACTIVE); intr_idx++) {
@@ -2576,9 +2570,8 @@ static int vxge_add_isr(struct vxgedev *vdev)
 		vdev->vxge_entries[intr_cnt].in_use = 1;
 		vdev->vxge_entries[intr_cnt].arg = &vdev->vpaths[0];
 	}
-INTA_MODE:
-#endif
 
+INTA_MODE:
 	if (vdev->config.intr_type == INTA) {
 		snprintf(vdev->desc[0], VXGE_INTR_STRLEN,
 			"%s:vxge:INTA", vdev->ndev->name);
@@ -3889,12 +3882,12 @@ static void vxge_device_config_init(struct vxge_hw_device_config *device_config,
 	if (max_mac_vpath > VXGE_MAX_MAC_ADDR_COUNT)
 		max_mac_vpath = VXGE_MAX_MAC_ADDR_COUNT;
 
-#ifndef CONFIG_PCI_MSI
-	vxge_debug_init(VXGE_ERR,
-		"%s: This Kernel does not support "
-		"MSI-X. Defaulting to INTA", VXGE_DRIVER_NAME);
-	*intr_type = INTA;
-#endif
+	if (!IS_ENABLED(CONFIG_PCI_MSI)) {
+		vxge_debug_init(VXGE_ERR,
+			"%s: This Kernel does not support "
+			"MSI-X. Defaulting to INTA", VXGE_DRIVER_NAME);
+		*intr_type = INTA;
+	}
 
 	/* Configure whether MSI-X or IRQL. */
 	switch (*intr_type) {
-- 
2.7.0

[PATCH v2 6/7] net: nb8800: avoid uninitialized variable warning

[Arnd Bergmann]

The nb8800_poll() function initializes the 'next' variable in the
loop looking for new input data. We know this will be called at
least once because 'budget' is a guaranteed to be a positive number
when we enter the function, but the compiler doesn't know that
and warns when the variable is used later:

drivers/net/ethernet/aurora/nb8800.c: In function 'nb8800_poll':
drivers/net/ethernet/aurora/nb8800.c:350:21: warning: 'next' may be used uninitialized in this function [-Wmaybe-uninitialized]

Changing the 'while() {}' loop to 'do {} while()' makes it obvious
to the compiler what is going on so it no longer warns.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mans Rullgard <mans@mansr.com>
---
 drivers/net/ethernet/aurora/nb8800.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/aurora/nb8800.c b/drivers/net/ethernet/aurora/nb8800.c
index ecc4a334c507..f71ab2647a3b 100644
--- a/drivers/net/ethernet/aurora/nb8800.c
+++ b/drivers/net/ethernet/aurora/nb8800.c
@@ -302,7 +302,7 @@ static int nb8800_poll(struct napi_struct *napi, int budget)
 	nb8800_tx_done(dev);
 
 again:
-	while (work < budget) {
+	do {
 		struct nb8800_rx_buf *rxb;
 		unsigned int len;
 
@@ -330,7 +330,7 @@ again:
 		rxd->report = 0;
 		last = next;
 		work++;
-	}
+	} while (work < budget);
 
 	if (work) {
 		priv->rx_descs[last].desc.config |= DESC_EOC;
-- 
2.7.0

[PATCH v2 7/7] net: tg3: avoid uninitialized variable warning

[Arnd Bergmann]

The tg3_set_eeprom() function correctly initializes the 'start' variable,
but gcc generates a false warning:

drivers/net/ethernet/broadcom/tg3.c: In function 'tg3_set_eeprom':
drivers/net/ethernet/broadcom/tg3.c:12057:4: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]

I have not come up with a way to restructure the code in a way that
avoids the warning without making it less readable, so this adds an
initialization for the declaration to shut up that warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/ethernet/broadcom/tg3.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 9293675df7ba..49eea8981332 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -12016,7 +12016,7 @@ static int tg3_set_eeprom(struct net_device *dev, struct ethtool_eeprom *eeprom,
 	int ret;
 	u32 offset, len, b_offset, odd_len;
 	u8 *buf;
-	__be32 start, end;
+	__be32 start = 0, end;
 
 	if (tg3_flag(tp, NO_NVRAM) ||
 	    eeprom->magic != TG3_EEPROM_MAGIC)
-- 
2.7.0

Re: [PATCH v2 0/7] network driver fixes

[David Miller]

From: Arnd Bergmann <arnd@arndb.de>
Date: Fri, 29 Jan 2016 12:39:08 +0100

> This is an updated series of fixes for the network device drivers
> that showed warnings in ARM randconfig.
> 
> Changes since v1 are:
> 
> dropped "net: macb: avoid uninitialized variables", already fixed in net-next
> 
> dropped "net: fddi/defxx: avoid warning about uninitialized variable
> 	use", already fixed in net-next
> 
> added missing barriers in "net: moxart: use correct accessors for
> 	DMA memory"
> 
> clarified "net: bgmac: clarify CONFIG_BCMA dependency" changelog

Series applied, thanks.