5 files changed, 104 insertions, 75 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 8e2be24f3fe4..832739f38db4 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1341,18 +1341,24 @@ static int bond_compute_features(struct bonding *bond)
         int i;
 
         features &= ~(NETIF_F_ALL_CSUM | BOND_VLAN_FEATURES);
-        features |= NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
-                    NETIF_F_GSO_MASK | NETIF_F_NO_CSUM;
+        features |=  NETIF_F_GSO_MASK | NETIF_F_NO_CSUM;
+
+        if (!bond->first_slave)
+                goto done;
+
+        features &= ~NETIF_F_ONE_FOR_ALL;
 
         bond_for_each_slave(bond, slave, i) {
-                features = netdev_compute_features(features,
-                                                   slave->dev->features);
+                features = netdev_increment_features(features,
+                                                     slave->dev->features,
+                                                     NETIF_F_ONE_FOR_ALL);
                 if (slave->dev->hard_header_len > max_hard_header_len)
                         max_hard_header_len = slave->dev->hard_header_len;
         }
 
+done:
         features |= (bond_dev->features & BOND_VLAN_FEATURES);
-        bond_dev->features = features;
+        bond_dev->features = netdev_fix_features(features, NULL);
         bond_dev->hard_header_len = max_hard_header_len;
 
         return 0;
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 64875859d654..c8bcb59adfdf 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -541,6 +541,14 @@ struct net_device
 #define NETIF_F_V6_CSUM         (NETIF_F_GEN_CSUM | NETIF_F_IPV6_CSUM)
 #define NETIF_F_ALL_CSUM        (NETIF_F_V4_CSUM | NETIF_F_V6_CSUM)
 
+        /*
+         * If one device supports one of these features, then enable them
+         * for all in netdev_increment_features.
+         */
+#define NETIF_F_ONE_FOR_ALL     (NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ROBUST | \
+                                 NETIF_F_SG | NETIF_F_HIGHDMA | \
+                                 NETIF_F_FRAGLIST)
+
         /* Interface index. Unique device identifier    */
         int                     ifindex;
         int                     iflink;
@@ -1698,7 +1706,9 @@ extern char *netdev_drivername(const struct net_device *dev, char *buffer, int l
 
 extern void linkwatch_run_queue(void);
 
-extern int netdev_compute_features(unsigned long all, unsigned long one);
+unsigned long netdev_increment_features(unsigned long all, unsigned long one,
+                                        unsigned long mask);
+unsigned long netdev_fix_features(unsigned long features, const char *name);
 
 static inline int net_gso_ok(int features, int gso_type)
 {
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 22ba8632196f..6c023f0f8252 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -179,5 +179,5 @@ void br_dev_setup(struct net_device *dev)
 
         dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
                         NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX |
-                        NETIF_F_NETNS_LOCAL;
+                        NETIF_F_NETNS_LOCAL | NETIF_F_GSO;
 }
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index 573e20f7dba4..0a09ccf68c1c 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -347,15 +347,21 @@ int br_min_mtu(const struct net_bridge *br)
 void br_features_recompute(struct net_bridge *br)
 {
         struct net_bridge_port *p;
-        unsigned long features;
+        unsigned long features, mask;
 
-        features = br->feature_mask;
+        features = mask = br->feature_mask;
+        if (list_empty(&br->port_list))
+                goto done;
+
+        features &= ~NETIF_F_ONE_FOR_ALL;
 
         list_for_each_entry(p, &br->port_list, list) {
-                features = netdev_compute_features(features, p->dev->features);
+                features = netdev_increment_features(features,
+                                                     p->dev->features, mask);
         }
 
-        br->dev->features = features;
+done:
+        br->dev->features = netdev_fix_features(features, NULL);
 }
 
 /* called with RTNL */
diff --git a/net/core/dev.c b/net/core/dev.c
index b8a4fd0806af..d9038e328cc1 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3947,6 +3947,46 @@ static void netdev_init_queue_locks(struct net_device *dev)
         __netdev_init_queue_locks_one(dev, &dev->rx_queue, NULL);
 }
 
+unsigned long netdev_fix_features(unsigned long features, const char *name)
+{
+        /* Fix illegal SG+CSUM combinations. */
+        if ((features & NETIF_F_SG) &&
+            !(features & NETIF_F_ALL_CSUM)) {
+                if (name)
+                        printk(KERN_NOTICE "%s: Dropping NETIF_F_SG since no "
+                               "checksum feature.\n", name);
+                features &= ~NETIF_F_SG;
+        }
+
+        /* TSO requires that SG is present as well. */
+        if ((features & NETIF_F_TSO) && !(features & NETIF_F_SG)) {
+                if (name)
+                        printk(KERN_NOTICE "%s: Dropping NETIF_F_TSO since no "
+                               "SG feature.\n", name);
+                features &= ~NETIF_F_TSO;
+        }
+
+        if (features & NETIF_F_UFO) {
+                if (!(features & NETIF_F_GEN_CSUM)) {
+                        if (name)
+                                printk(KERN_ERR "%s: Dropping NETIF_F_UFO "
+                                       "since no NETIF_F_HW_CSUM feature.\n",
+                                       name);
+                        features &= ~NETIF_F_UFO;
+                }
+
+                if (!(features & NETIF_F_SG)) {
+                        if (name)
+                                printk(KERN_ERR "%s: Dropping NETIF_F_UFO "
+                                       "since no NETIF_F_SG feature.\n", name);
+                        features &= ~NETIF_F_UFO;
+                }
+        }
+
+        return features;
+}
+EXPORT_SYMBOL(netdev_fix_features);
+
 /**
  *      register_netdevice      - register a network device
  *      @dev: device to register
@@ -4032,36 +4072,7 @@ int register_netdevice(struct net_device *dev)
                 dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM);
         }
 
-
-        /* Fix illegal SG+CSUM combinations. */
-        if ((dev->features & NETIF_F_SG) &&
-            !(dev->features & NETIF_F_ALL_CSUM)) {
-                printk(KERN_NOTICE "%s: Dropping NETIF_F_SG since no checksum feature.\n",
-                       dev->name);
-                dev->features &= ~NETIF_F_SG;
-        }
-
-        /* TSO requires that SG is present as well. */
-        if ((dev->features & NETIF_F_TSO) &&
-            !(dev->features & NETIF_F_SG)) {
-                printk(KERN_NOTICE "%s: Dropping NETIF_F_TSO since no SG feature.\n",
-                       dev->name);
-                dev->features &= ~NETIF_F_TSO;
-        }
-        if (dev->features & NETIF_F_UFO) {
-                if (!(dev->features & NETIF_F_HW_CSUM)) {
-                        printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no "
-                                        "NETIF_F_HW_CSUM feature.\n",
-                                                        dev->name);
-                        dev->features &= ~NETIF_F_UFO;
-                }
-                if (!(dev->features & NETIF_F_SG)) {
-                        printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no "
-                                        "NETIF_F_SG feature.\n",
-                                        dev->name);
-                        dev->features &= ~NETIF_F_UFO;
-                }
-        }
+        dev->features = netdev_fix_features(dev->features, dev->name);
 
         /* Enable software GSO if SG is supported. */
         if (dev->features & NETIF_F_SG)
@@ -4700,49 +4711,45 @@ static int __init netdev_dma_register(void) { return -ENODEV; }
 #endif /* CONFIG_NET_DMA */
 
 /**
- *      netdev_compute_feature - compute conjunction of two feature sets
- *      @all: first feature set
- *      @one: second feature set
+ *      netdev_increment_features - increment feature set by one
+ *      @all: current feature set
+ *      @one: new feature set
+ *      @mask: mask feature set
  *
  *      Computes a new feature set after adding a device with feature set
- *      @one to the master device with current feature set @all.  Returns
- *      the new feature set.
+ *      @one to the master device with current feature set @all.  Will not
+ *      enable anything that is off in @mask. Returns the new feature set.
  */
-int netdev_compute_features(unsigned long all, unsigned long one)
-{
-        /* if device needs checksumming, downgrade to hw checksumming */
-        if (all & NETIF_F_NO_CSUM && !(one & NETIF_F_NO_CSUM))
-                all ^= NETIF_F_NO_CSUM | NETIF_F_HW_CSUM;
-
-        /* if device can't do all checksum, downgrade to ipv4/ipv6 */
-        if (all & NETIF_F_HW_CSUM && !(one & NETIF_F_HW_CSUM))
-                all ^= NETIF_F_HW_CSUM
-                        | NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
-
-        if (one & NETIF_F_GSO)
-                one |= NETIF_F_GSO_SOFTWARE;
-        one |= NETIF_F_GSO;
-
-        /*
-         * If even one device supports a GSO protocol with software fallback,
-         * enable it for all.
-         */
-        all |= one & NETIF_F_GSO_SOFTWARE;
+unsigned long netdev_increment_features(unsigned long all, unsigned long one,
+                                        unsigned long mask)
+{
+        /* If device needs checksumming, downgrade to it. */
+        if (all & NETIF_F_NO_CSUM && !(one & NETIF_F_NO_CSUM))
+                all ^= NETIF_F_NO_CSUM | (one & NETIF_F_ALL_CSUM);
+        else if (mask & NETIF_F_ALL_CSUM) {
+                /* If one device supports v4/v6 checksumming, set for all. */
+                if (one & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM) &&
+                    !(all & NETIF_F_GEN_CSUM)) {
+                        all &= ~NETIF_F_ALL_CSUM;
+                        all |= one & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM);
+                }
 
-        /* If even one device supports robust GSO, enable it for all. */
-        if (one & NETIF_F_GSO_ROBUST)
-                all |= NETIF_F_GSO_ROBUST;
+                /* If one device supports hw checksumming, set for all. */
+                if (one & NETIF_F_GEN_CSUM && !(all & NETIF_F_GEN_CSUM)) {
+                        all &= ~NETIF_F_ALL_CSUM;
+                        all |= NETIF_F_HW_CSUM;
+                }
+        }
 
-        all &= one | NETIF_F_LLTX;
+        one |= NETIF_F_ALL_CSUM;
 
-        if (!(all & NETIF_F_ALL_CSUM))
-                all &= ~NETIF_F_SG;
-        if (!(all & NETIF_F_SG))
-                all &= ~NETIF_F_GSO_MASK;
+        one |= all & NETIF_F_ONE_FOR_ALL;
+        all &= one | NETIF_F_LLTX | NETIF_F_GSO;
+        all |= one & mask & NETIF_F_ONE_FOR_ALL;
 
         return all;
 }
-EXPORT_SYMBOL(netdev_compute_features);
+EXPORT_SYMBOL(netdev_increment_features);
 
 static struct hlist_head *netdev_create_hash(void)
 {