[PATCH net v2 08/12] net: au1000: restore receive filtering before enabling RX

[Florian Fainelli]

MAC initialization overwrites the receive mode, dropping promiscuous and
multicast settings after a watchdog reset without notifying the network
stack. Restore the requested filtering before the control write that
enables RX, avoiding a window with the wrong filter.

Factor receive-mode programming into a helper shared by initialization
and the receive-mode callback. Hold the address-list lock before the
device lock through initialization so the filter snapshot stays current.
Protect callback control-register updates with the device lock as well.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
 drivers/net/ethernet/amd/au1000_eth.c | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/amd/au1000_eth.c b/drivers/net/ethernet/amd/au1000_eth.c
index f127c0184036..67f4899c34a6 100644
--- a/drivers/net/ethernet/amd/au1000_eth.c
+++ b/drivers/net/ethernet/amd/au1000_eth.c
@@ -683,6 +683,8 @@ static const struct ethtool_ops au1000_ethtool_ops = {
 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
 };
 
+static u32 au1000_rx_mode(struct net_device *dev, u32 reg);
+
 /*
  * Initialize the interface.
  *
@@ -704,6 +706,7 @@ static int au1000_init(struct net_device *dev)
 	/* bring the device out of reset */
 	au1000_enable_mac(dev, 1);
 
+	netif_addr_lock_bh(dev);
 	spin_lock_irqsave(&aup->lock, flags);
 
 	writel(0, &aup->mac->control);
@@ -736,11 +739,14 @@ static int au1000_init(struct net_device *dev)
 		control |= MAC_FULL_DUPLEX;
 	}
 
+	control = au1000_rx_mode(dev, control);
+
 	writel(control, &aup->mac->control);
 	writel(0x8100, &aup->mac->vlan1_tag); /* activate vlan support */
 	wmb(); /* drain writebuffer */
 
 	spin_unlock_irqrestore(&aup->lock, flags);
+	netif_addr_unlock_bh(dev);
 	return 0;
 }
 
@@ -1034,13 +1040,12 @@ static void au1000_tx_timeout(struct net_device *dev, unsigned int txqueue)
 	netif_wake_queue(dev);
 }
 
-static void au1000_multicast_list(struct net_device *dev)
+/* Caller holds the address-list lock and aup->lock. */
+static u32 au1000_rx_mode(struct net_device *dev, u32 reg)
 {
 	struct au1000_private *aup = netdev_priv(dev);
-	u32 reg;
 
 	netif_dbg(aup, drv, dev, "%s: flags=%x\n", __func__, dev->flags);
-	reg = readl(&aup->mac->control);
 	if (dev->flags & IFF_PROMISC) {			/* Set promiscuous. */
 		reg |= MAC_PROMISCUOUS;
 	} else if ((dev->flags & IFF_ALLMULTI)  ||
@@ -1061,7 +1066,19 @@ static void au1000_multicast_list(struct net_device *dev)
 		reg &= ~(MAC_PROMISCUOUS | MAC_PASS_ALL_MULTI);
 		reg |= MAC_HASH_MODE;
 	}
+	return reg;
+}
+
+static void au1000_multicast_list(struct net_device *dev)
+{
+	struct au1000_private *aup = netdev_priv(dev);
+	unsigned long flags;
+	u32 reg;
+
+	spin_lock_irqsave(&aup->lock, flags);
+	reg = au1000_rx_mode(dev, readl(&aup->mac->control));
 	writel(reg, &aup->mac->control);
+	spin_unlock_irqrestore(&aup->lock, flags);
 }
 
 static const struct net_device_ops au1000_netdev_ops = {
-- 
2.53.0