1 files changed, 46 insertions, 28 deletions

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index a09d507c5b03..af238026ac3c 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -34,10 +34,10 @@ static const char fmt_dec[] = "%d\n";
 static const char fmt_ulong[] = "%lu\n";
 static const char fmt_u64[] = "%llu\n";
 
-/* Caller holds RTNL or dev_base_lock */
+/* Caller holds RTNL or RCU */
 static inline int dev_isalive(const struct net_device *dev)
 {
-	return dev->reg_state <= NETREG_REGISTERED;
+	return READ_ONCE(dev->reg_state) <= NETREG_REGISTERED;
 }
 
 /* use same locking rules as GIF* ioctl's */
@@ -48,10 +48,10 @@ static ssize_t netdev_show(const struct device *dev,
 	struct net_device *ndev = to_net_dev(dev);
 	ssize_t ret = -EINVAL;
 
-	read_lock(&dev_base_lock);
+	rcu_read_lock();
 	if (dev_isalive(ndev))
 		ret = (*format)(ndev, buf);
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
 
 	return ret;
 }
@@ -60,7 +60,7 @@ static ssize_t netdev_show(const struct device *dev,
 #define NETDEVICE_SHOW(field, format_string)				\
 static ssize_t format_##field(const struct net_device *dev, char *buf)	\
 {									\
-	return sysfs_emit(buf, format_string, dev->field);		\
+	return sysfs_emit(buf, format_string, READ_ONCE(dev->field));		\
 }									\
 static ssize_t field##_show(struct device *dev,				\
 			    struct device_attribute *attr, char *buf)	\
@@ -125,7 +125,7 @@ static DEVICE_ATTR_RO(iflink);
 
 static ssize_t format_name_assign_type(const struct net_device *dev, char *buf)
 {
-	return sysfs_emit(buf, fmt_dec, dev->name_assign_type);
+	return sysfs_emit(buf, fmt_dec, READ_ONCE(dev->name_assign_type));
 }
 
 static ssize_t name_assign_type_show(struct device *dev,
@@ -135,24 +135,28 @@ static ssize_t name_assign_type_show(struct device *dev,
 	struct net_device *ndev = to_net_dev(dev);
 	ssize_t ret = -EINVAL;
 
-	if (ndev->name_assign_type != NET_NAME_UNKNOWN)
+	if (READ_ONCE(ndev->name_assign_type) != NET_NAME_UNKNOWN)
 		ret = netdev_show(dev, attr, buf, format_name_assign_type);
 
 	return ret;
 }
 static DEVICE_ATTR_RO(name_assign_type);
 
-/* use same locking rules as GIFHWADDR ioctl's */
+/* use same locking rules as GIFHWADDR ioctl's (dev_get_mac_address()) */
 static ssize_t address_show(struct device *dev, struct device_attribute *attr,
 			    char *buf)
 {
 	struct net_device *ndev = to_net_dev(dev);
 	ssize_t ret = -EINVAL;
 
-	read_lock(&dev_base_lock);
+	down_read(&dev_addr_sem);
+
+	rcu_read_lock();
 	if (dev_isalive(ndev))
 		ret = sysfs_format_mac(buf, ndev->dev_addr, ndev->addr_len);
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
+
+	up_read(&dev_addr_sem);
 	return ret;
 }
 static DEVICE_ATTR_RO(address);
@@ -161,10 +165,13 @@ static ssize_t broadcast_show(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
 	struct net_device *ndev = to_net_dev(dev);
+	int ret = -EINVAL;
 
+	rcu_read_lock();
 	if (dev_isalive(ndev))
-		return sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
-	return -EINVAL;
+		ret = sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
+	rcu_read_unlock();
+	return ret;
 }
 static DEVICE_ATTR_RO(broadcast);
 
@@ -318,11 +325,9 @@ static ssize_t operstate_show(struct device *dev,
 	const struct net_device *netdev = to_net_dev(dev);
 	unsigned char operstate;
 
-	read_lock(&dev_base_lock);
-	operstate = netdev->operstate;
+	operstate = READ_ONCE(netdev->operstate);
 	if (!netif_running(netdev))
 		operstate = IF_OPER_DOWN;
-	read_unlock(&dev_base_lock);
 
 	if (operstate >= ARRAY_SIZE(operstates))
 		return -EINVAL; /* should not happen */
@@ -680,14 +685,14 @@ static ssize_t netstat_show(const struct device *d,
 	WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
 		offset % sizeof(u64) != 0);
 
-	read_lock(&dev_base_lock);
+	rcu_read_lock();
 	if (dev_isalive(dev)) {
 		struct rtnl_link_stats64 temp;
 		const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
 
 		ret = sysfs_emit(buf, fmt_u64, *(u64 *)(((u8 *)stats) + offset));
 	}
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
 	return ret;
 }
 
@@ -1454,6 +1459,9 @@ static const struct attribute_group dql_group = {
 	.name  = "byte_queue_limits",
 	.attrs  = dql_attrs,
 };
+#else
+/* Fake declaration, all the code using it should be dead */
+extern const struct attribute_group dql_group;
 #endif /* CONFIG_BQL */
 
 #ifdef CONFIG_XPS
@@ -1691,6 +1699,15 @@ static const struct kobj_type netdev_queue_ktype = {
 	.get_ownership = netdev_queue_get_ownership,
 };
 
+static bool netdev_uses_bql(const struct net_device *dev)
+{
+	if (dev->features & NETIF_F_LLTX ||
+	    dev->priv_flags & IFF_NO_QUEUE)
+		return false;
+
+	return IS_ENABLED(CONFIG_BQL);
+}
+
 static int netdev_queue_add_kobject(struct net_device *dev, int index)
 {
 	struct netdev_queue *queue = dev->_tx + index;
@@ -1708,11 +1725,11 @@ static int netdev_queue_add_kobject(struct net_device *dev, int index)
 	if (error)
 		goto err;
 
-#ifdef CONFIG_BQL
-	error = sysfs_create_group(kobj, &dql_group);
-	if (error)
-		goto err;
-#endif
+	if (netdev_uses_bql(dev)) {
+		error = sysfs_create_group(kobj, &dql_group);
+		if (error)
+			goto err;
+	}
 
 	kobject_uevent(kobj, KOBJ_ADD);
 	return 0;
@@ -1733,9 +1750,9 @@ static int tx_queue_change_owner(struct net_device *ndev, int index,
 	if (error)
 		return error;
 
-#ifdef CONFIG_BQL
-	error = sysfs_group_change_owner(kobj, &dql_group, kuid, kgid);
-#endif
+	if (netdev_uses_bql(ndev))
+		error = sysfs_group_change_owner(kobj, &dql_group, kuid, kgid);
+
 	return error;
 }
 #endif /* CONFIG_SYSFS */
@@ -1767,9 +1784,10 @@ netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
 
 		if (!refcount_read(&dev_net(dev)->ns.count))
 			queue->kobj.uevent_suppress = 1;
-#ifdef CONFIG_BQL
-		sysfs_remove_group(&queue->kobj, &dql_group);
-#endif
+
+		if (netdev_uses_bql(dev))
+			sysfs_remove_group(&queue->kobj, &dql_group);
+
 		kobject_put(&queue->kobj);
 	}