Merge branch 'devlink-make-ethtool-compat-reliable'

Jakub Kicinski says:

====================
devlink: make ethtool compat reliable

This is a follow up to the series which added device flash
updates via devlink. I went with the approach of adding a
new NDO in the end. It seems to end up looking cleaner.

First patch removes the option to build devlink as a module.
Users can still decide to not build it, but the module option
ends up not being worth the maintenance cost.

Next two patches add a NDO which can be used to ask the driver
to return a devlink instance associated with a given netdev,
instead of iterating over devlink ports. Drivers which implement
this NDO must take into account the potential impact on the
visibility of the devlink instance.

With the new NDO in place we can remove NFP ethtool flash update
code.

Fifth patch makes sure we hold a reference to dev while
callbacks are active.

Last but not least the NULL-check of devlink->ops is moved
to instance allocation time.

Last but not least missing checks for devlink->ops are added.
There is currently no driver registering devlink without ops,
so can just fix this in -next.

v2 (Michal): add netdev_to_devlink() in patch 3.
v3 (Florian):
 - add missing checks for devlink->ops;
 - move locking/holding into devlink_compat_ functions.
v4 (Jiri):
 - hold devlink_mutex around callbacks (patch 2);
 - require non-NULL ops (patch 6).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/infiniband/hw/bnxt_re/Kconfig

 config INFINIBAND_BNXT_RE
     tristate "Broadcom Netxtreme HCA support"
     depends on ETHERNET && NETDEVICES && PCI && INET && DCB
-    depends on MAY_USE_DEVLINK
     select NET_VENDOR_BROADCOM
     select BNXT
     ---help---

drivers/infiniband/hw/mlx4/Kconfig

@@ -2,7 +2,6 @@ config MLX4_INFINIBAND
 	tristate "Mellanox ConnectX HCA support"
 	depends on NETDEVICES && ETHERNET && PCI && INET
 	depends on INFINIBAND_USER_ACCESS || !INFINIBAND_USER_ACCESS
-	depends on MAY_USE_DEVLINK
 	select NET_VENDOR_MELLANOX
 	select MLX4_CORE
 	---help---

drivers/net/Kconfig

@@ -505,7 +505,6 @@ source "drivers/net/hyperv/Kconfig"
 config NETDEVSIM
 	tristate "Simulated networking device"
 	depends on DEBUG_FS
-	depends on MAY_USE_DEVLINK
 	help
 	  This driver is a developer testing tool and software model that can
 	  be used to test various control path networking APIs, especially

drivers/net/ethernet/broadcom/Kconfig

@@ -194,7 +194,6 @@ config SYSTEMPORT
 config BNXT
 	tristate "Broadcom NetXtreme-C/E support"
 	depends on PCI
-	depends on MAY_USE_DEVLINK
 	select FW_LOADER
 	select LIBCRC32C
 	---help---

drivers/net/ethernet/cavium/Kconfig

@@ -64,7 +64,6 @@ config CAVIUM_PTP
 config LIQUIDIO
 	tristate "Cavium LiquidIO support"
 	depends on 64BIT && PCI
-	depends on MAY_USE_DEVLINK
 	depends on PCI
 	imply PTP_1588_CLOCK
 	select FW_LOADER

drivers/net/ethernet/mellanox/mlx4/Kconfig

@@ -4,7 +4,6 @@
 
 config MLX4_EN
 	tristate "Mellanox Technologies 1/10/40Gbit Ethernet support"
-	depends on MAY_USE_DEVLINK
 	depends on PCI && NETDEVICES && ETHERNET && INET
 	select MLX4_CORE
 	imply PTP_1588_CLOCK

drivers/net/ethernet/mellanox/mlx5/core/Kconfig

@@ -4,7 +4,6 @@
 
 config MLX5_CORE
 	tristate "Mellanox 5th generation network adapters (ConnectX series) core driver"
-	depends on MAY_USE_DEVLINK
 	depends on PCI
 	imply PTP_1588_CLOCK
 	imply VXLAN

drivers/net/ethernet/mellanox/mlxsw/Kconfig

@@ -4,7 +4,6 @@
 
 config MLXSW_CORE
 	tristate "Mellanox Technologies Switch ASICs support"
-	depends on MAY_USE_DEVLINK
 	---help---
 	  This driver supports Mellanox Technologies Switch ASICs family.
 

drivers/net/ethernet/netronome/Kconfig

@@ -19,7 +19,6 @@ config NFP
 	tristate "Netronome(R) NFP4000/NFP6000 NIC driver"
 	depends on PCI && PCI_MSI
 	depends on VXLAN || VXLAN=n
-	depends on MAY_USE_DEVLINK
 	---help---
 	  This driver supports the Netronome(R) NFP4000/NFP6000 based
 	  cards working as a advanced Ethernet NIC.  It works with both

drivers/net/ethernet/netronome/nfp/nfp_app.h

@@ -433,4 +433,6 @@ int nfp_app_nic_vnic_alloc(struct nfp_app *app, struct nfp_net *nn,
 int nfp_app_nic_vnic_init_phy_port(struct nfp_pf *pf, struct nfp_app *app,
 				   struct nfp_net *nn, unsigned int id);
 
+struct devlink *nfp_devlink_get_devlink(struct net_device *netdev);
+
 #endif

drivers/net/ethernet/netronome/nfp/nfp_devlink.c

@@ -376,3 +376,14 @@ void nfp_devlink_port_unregister(struct nfp_port *port)
 {
 	devlink_port_unregister(&port->dl_port);
 }
+
+struct devlink *nfp_devlink_get_devlink(struct net_device *netdev)
+{
+	struct nfp_app *app;
+
+	app = nfp_app_from_netdev(netdev);
+	if (!app)
+		return NULL;
+
+	return priv_to_devlink(app->pf);
+}

drivers/net/ethernet/netronome/nfp/nfp_net_common.c

@@ -3531,6 +3531,7 @@ const struct net_device_ops nfp_net_netdev_ops = {
 	.ndo_udp_tunnel_del	= nfp_net_del_vxlan_port,
 	.ndo_bpf		= nfp_net_xdp,
 	.ndo_get_port_parent_id	= nfp_port_get_port_parent_id,
+	.ndo_get_devlink	= nfp_devlink_get_devlink,
 };
 
 /**

drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c

@@ -1234,28 +1234,6 @@ static int nfp_net_set_channels(struct net_device *netdev,
 	return nfp_net_set_num_rings(nn, total_rx, total_tx);
 }
 
-static int
-nfp_net_flash_device(struct net_device *netdev, struct ethtool_flash *flash)
-{
-	struct nfp_app *app;
-	int ret;
-
-	if (flash->region != ETHTOOL_FLASH_ALL_REGIONS)
-		return -EOPNOTSUPP;
-
-	app = nfp_app_from_netdev(netdev);
-	if (!app)
-		return -EOPNOTSUPP;
-
-	dev_hold(netdev);
-	rtnl_unlock();
-	ret = nfp_flash_update_common(app->pf, flash->data, NULL);
-	rtnl_lock();
-	dev_put(netdev);
-
-	return ret;
-}
-
 static const struct ethtool_ops nfp_net_ethtool_ops = {
 	.get_drvinfo		= nfp_net_get_drvinfo,
 	.get_link		= ethtool_op_get_link,
@@ -1266,7 +1244,6 @@ static const struct ethtool_ops nfp_net_ethtool_ops = {
 	.get_sset_count		= nfp_net_get_sset_count,
 	.get_rxnfc		= nfp_net_get_rxnfc,
 	.set_rxnfc		= nfp_net_set_rxnfc,
-	.flash_device		= nfp_net_flash_device,
 	.get_rxfh_indir_size	= nfp_net_get_rxfh_indir_size,
 	.get_rxfh_key_size	= nfp_net_get_rxfh_key_size,
 	.get_rxfh		= nfp_net_get_rxfh,
@@ -1292,7 +1269,6 @@ const struct ethtool_ops nfp_port_ethtool_ops = {
 	.get_strings		= nfp_port_get_strings,
 	.get_ethtool_stats	= nfp_port_get_stats,
 	.get_sset_count		= nfp_port_get_sset_count,
-	.flash_device		= nfp_net_flash_device,
 	.set_dump		= nfp_app_set_dump,
 	.get_dump_flag		= nfp_app_get_dump_flag,
 	.get_dump_data		= nfp_app_get_dump_data,

drivers/net/ethernet/netronome/nfp/nfp_net_repr.c

@@ -273,6 +273,7 @@ const struct net_device_ops nfp_repr_netdev_ops = {
 	.ndo_set_features	= nfp_port_set_features,
 	.ndo_set_mac_address    = eth_mac_addr,
 	.ndo_get_port_parent_id	= nfp_port_get_port_parent_id,
+	.ndo_get_devlink	= nfp_devlink_get_devlink,
 };
 
 void

include/linux/netdevice.h

@@ -941,6 +941,8 @@ struct dev_ifalias {
 	char ifalias[];
 };
 
+struct devlink;
+
 /*
  * This structure defines the management hooks for network devices.
  * The following hooks can be defined; unless noted otherwise, they are
@@ -1249,6 +1251,10 @@ struct dev_ifalias {
  *	that got dropped are freed/returned via xdp_return_frame().
  *	Returns negative number, means general error invoking ndo, meaning
  *	no frames were xmit'ed and core-caller will free all frames.
+ * struct devlink *(*ndo_get_devlink)(struct net_device *dev);
+ *	Get devlink instance associated with a given netdev.
+ *	Called with a reference on the netdevice and devlink locks only,
+ *	rtnl_lock is not held.
  */
 struct net_device_ops {
 	int			(*ndo_init)(struct net_device *dev);
@@ -1447,6 +1453,7 @@ struct net_device_ops {
 						u32 flags);
 	int			(*ndo_xsk_async_xmit)(struct net_device *dev,
 						      u32 queue_id);
+	struct devlink *	(*ndo_get_devlink)(struct net_device *dev);
 };
 
 /**

include/net/devlink.h

@@ -538,6 +538,15 @@ static inline struct devlink *priv_to_devlink(void *priv)
 	return container_of(priv, struct devlink, priv);
 }
 
+static inline struct devlink *netdev_to_devlink(struct net_device *dev)
+{
+#if IS_ENABLED(CONFIG_NET_DEVLINK)
+	if (dev->netdev_ops->ndo_get_devlink)
+		return dev->netdev_ops->ndo_get_devlink(dev);
+#endif
+	return NULL;
+}
+
 struct ib_device;
 
 #if IS_ENABLED(CONFIG_NET_DEVLINK)
@@ -707,6 +716,10 @@ devlink_health_reporter_priv(struct devlink_health_reporter *reporter);
 int devlink_health_report(struct devlink_health_reporter *reporter,
 			  const char *msg, void *priv_ctx);
 
+void devlink_compat_running_version(struct net_device *dev,
+				    char *buf, size_t len);
+int devlink_compat_flash_update(struct net_device *dev, const char *file_name);
+
 #else
 
 static inline struct devlink *devlink_alloc(const struct devlink_ops *ops,
@@ -1190,13 +1203,7 @@ devlink_health_report(struct devlink_health_reporter *reporter,
 {
 	return 0;
 }
-#endif
 
-#if IS_REACHABLE(CONFIG_NET_DEVLINK)
-void devlink_compat_running_version(struct net_device *dev,
-				    char *buf, size_t len);
-int devlink_compat_flash_update(struct net_device *dev, const char *file_name);
-#else
 static inline void
 devlink_compat_running_version(struct net_device *dev, char *buf, size_t len)
 {

net/Kconfig

@@ -429,21 +429,12 @@ config NET_SOCK_MSG
 	  with the help of BPF programs.
 
 config NET_DEVLINK
-	tristate "Network physical/parent device Netlink interface"
+	bool "Network physical/parent device Netlink interface"
 	help
 	  Network physical/parent device Netlink interface provides
 	  infrastructure to support access to physical chip-wide config and
 	  monitoring.
 
-config MAY_USE_DEVLINK
-	tristate
-	default m if NET_DEVLINK=m
-	default y if NET_DEVLINK=y || NET_DEVLINK=n
-	help
-	  Drivers using the devlink infrastructure should have a dependency
-	  on MAY_USE_DEVLINK to ensure they do not cause link errors when
-	  devlink is a loadable module and the driver using it is built-in.
-
 config PAGE_POOL
        bool
 

net/core/devlink.c

@@ -723,7 +723,7 @@ static int devlink_port_type_set(struct devlink *devlink,
 {
 	int err;
 
-	if (devlink->ops && devlink->ops->port_type_set) {
+	if (devlink->ops->port_type_set) {
 		if (port_type == DEVLINK_PORT_TYPE_NOTSET)
 			return -EINVAL;
 		if (port_type == devlink_port->type)
@@ -760,7 +760,7 @@ static int devlink_port_split(struct devlink *devlink, u32 port_index,
 			      u32 count, struct netlink_ext_ack *extack)
 
 {
-	if (devlink->ops && devlink->ops->port_split)
+	if (devlink->ops->port_split)
 		return devlink->ops->port_split(devlink, port_index, count,
 						extack);
 	return -EOPNOTSUPP;
@@ -786,7 +786,7 @@ static int devlink_port_unsplit(struct devlink *devlink, u32 port_index,
 				struct netlink_ext_ack *extack)
 
 {
-	if (devlink->ops && devlink->ops->port_unsplit)
+	if (devlink->ops->port_unsplit)
 		return devlink->ops->port_unsplit(devlink, port_index, extack);
 	return -EOPNOTSUPP;
 }
@@ -961,7 +961,7 @@ static int devlink_nl_cmd_sb_pool_get_doit(struct sk_buff *skb,
 	if (err)
 		return err;
 
-	if (!devlink->ops || !devlink->ops->sb_pool_get)
+	if (!devlink->ops->sb_pool_get)
 		return -EOPNOTSUPP;
 
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
@@ -1017,7 +1017,7 @@ static int devlink_nl_cmd_sb_pool_get_dumpit(struct sk_buff *msg,
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
 		if (!net_eq(devlink_net(devlink), sock_net(msg->sk)) ||
-		    !devlink->ops || !devlink->ops->sb_pool_get)
+		    !devlink->ops->sb_pool_get)
 			continue;
 		mutex_lock(&devlink->lock);
 		list_for_each_entry(devlink_sb, &devlink->sb_list, list) {
@@ -1046,7 +1046,7 @@ static int devlink_sb_pool_set(struct devlink *devlink, unsigned int sb_index,
 {
 	const struct devlink_ops *ops = devlink->ops;
 
-	if (ops && ops->sb_pool_set)
+	if (ops->sb_pool_set)
 		return ops->sb_pool_set(devlink, sb_index, pool_index,
 					size, threshold_type);
 	return -EOPNOTSUPP;
@@ -1151,7 +1151,7 @@ static int devlink_nl_cmd_sb_port_pool_get_doit(struct sk_buff *skb,
 	if (err)
 		return err;
 
-	if (!devlink->ops || !devlink->ops->sb_port_pool_get)
+	if (!devlink->ops->sb_port_pool_get)
 		return -EOPNOTSUPP;
 
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
@@ -1213,7 +1213,7 @@ static int devlink_nl_cmd_sb_port_pool_get_dumpit(struct sk_buff *msg,
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
 		if (!net_eq(devlink_net(devlink), sock_net(msg->sk)) ||
-		    !devlink->ops || !devlink->ops->sb_port_pool_get)
+		    !devlink->ops->sb_port_pool_get)
 			continue;
 		mutex_lock(&devlink->lock);
 		list_for_each_entry(devlink_sb, &devlink->sb_list, list) {
@@ -1242,7 +1242,7 @@ static int devlink_sb_port_pool_set(struct devlink_port *devlink_port,
 {
 	const struct devlink_ops *ops = devlink_port->devlink->ops;
 
-	if (ops && ops->sb_port_pool_set)
+	if (ops->sb_port_pool_set)
 		return ops->sb_port_pool_set(devlink_port, sb_index,
 					     pool_index, threshold);
 	return -EOPNOTSUPP;
@@ -1355,7 +1355,7 @@ static int devlink_nl_cmd_sb_tc_pool_bind_get_doit(struct sk_buff *skb,
 	if (err)
 		return err;
 
-	if (!devlink->ops || !devlink->ops->sb_tc_pool_bind_get)
+	if (!devlink->ops->sb_tc_pool_bind_get)
 		return -EOPNOTSUPP;
 
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
@@ -1439,7 +1439,7 @@ devlink_nl_cmd_sb_tc_pool_bind_get_dumpit(struct sk_buff *msg,
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
 		if (!net_eq(devlink_net(devlink), sock_net(msg->sk)) ||
-		    !devlink->ops || !devlink->ops->sb_tc_pool_bind_get)
+		    !devlink->ops->sb_tc_pool_bind_get)
 			continue;
 
 		mutex_lock(&devlink->lock);
@@ -1471,7 +1471,7 @@ static int devlink_sb_tc_pool_bind_set(struct devlink_port *devlink_port,
 {
 	const struct devlink_ops *ops = devlink_port->devlink->ops;
 
-	if (ops && ops->sb_tc_pool_bind_set)
+	if (ops->sb_tc_pool_bind_set)
 		return ops->sb_tc_pool_bind_set(devlink_port, sb_index,
 						tc_index, pool_type,
 						pool_index, threshold);
@@ -1519,7 +1519,7 @@ static int devlink_nl_cmd_sb_occ_snapshot_doit(struct sk_buff *skb,
 	struct devlink_sb *devlink_sb = info->user_ptr[1];
 	const struct devlink_ops *ops = devlink->ops;
 
-	if (ops && ops->sb_occ_snapshot)
+	if (ops->sb_occ_snapshot)
 		return ops->sb_occ_snapshot(devlink, devlink_sb->index);
 	return -EOPNOTSUPP;
 }
@@ -1531,7 +1531,7 @@ static int devlink_nl_cmd_sb_occ_max_clear_doit(struct sk_buff *skb,
 	struct devlink_sb *devlink_sb = info->user_ptr[1];
 	const struct devlink_ops *ops = devlink->ops;
 
-	if (ops && ops->sb_occ_max_clear)
+	if (ops->sb_occ_max_clear)
 		return ops->sb_occ_max_clear(devlink, devlink_sb->index);
 	return -EOPNOTSUPP;
 }
@@ -1594,13 +1594,9 @@ static int devlink_nl_cmd_eswitch_get_doit(struct sk_buff *skb,
 					   struct genl_info *info)
 {
 	struct devlink *devlink = info->user_ptr[0];
-	const struct devlink_ops *ops = devlink->ops;
 	struct sk_buff *msg;
 	int err;
 
-	if (!ops)
-		return -EOPNOTSUPP;
-
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 	if (!msg)
 		return -ENOMEM;
@@ -1625,9 +1621,6 @@ static int devlink_nl_cmd_eswitch_set_doit(struct sk_buff *skb,
 	int err = 0;
 	u16 mode;
 
-	if (!ops)
-		return -EOPNOTSUPP;
-
 	if (info->attrs[DEVLINK_ATTR_ESWITCH_MODE]) {
 		if (!ops->eswitch_mode_set)
 			return -EOPNOTSUPP;
@@ -3869,7 +3862,7 @@ static int devlink_nl_cmd_info_get_doit(struct sk_buff *skb,
 	struct sk_buff *msg;
 	int err;
 
-	if (!devlink->ops || !devlink->ops->info_get)
+	if (!devlink->ops->info_get)
 		return -EOPNOTSUPP;
 
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
@@ -5232,6 +5225,9 @@ struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size)
 {
 	struct devlink *devlink;
 
+	if (WARN_ON(!ops))
+		return NULL;
+
 	devlink = kzalloc(sizeof(*devlink) + priv_size, GFP_KERNEL);
 	if (!devlink)
 		return NULL;
@@ -6091,7 +6087,7 @@ __devlink_param_driverinit_value_set(struct devlink *devlink,
 int devlink_param_driverinit_value_get(struct devlink *devlink, u32 param_id,
 				       union devlink_param_value *init_val)
 {
-	if (!devlink->ops || !devlink->ops->reload)
+	if (!devlink->ops->reload)
 		return -EOPNOTSUPP;
 
 	return __devlink_param_driverinit_value_get(&devlink->param_list,
@@ -6138,7 +6134,7 @@ int devlink_port_param_driverinit_value_get(struct devlink_port *devlink_port,
 {
 	struct devlink *devlink = devlink_port->devlink;
 
-	if (!devlink->ops || !devlink->ops->reload)
+	if (!devlink->ops->reload)
 		return -EOPNOTSUPP;
 
 	return __devlink_param_driverinit_value_get(&devlink_port->param_list,
@@ -6397,9 +6393,6 @@ static void __devlink_compat_running_version(struct devlink *devlink,
 	struct sk_buff *msg;
 	int rem, err;
 
-	if (!devlink->ops->info_get)
-		return;
-
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 	if (!msg)
 		return;
@@ -6431,71 +6424,54 @@ static void __devlink_compat_running_version(struct devlink *devlink,
 void devlink_compat_running_version(struct net_device *dev,
 				    char *buf, size_t len)
 {
-	struct devlink_port *devlink_port;
 	struct devlink *devlink;
 
+	dev_hold(dev);
+	rtnl_unlock();
+
 	mutex_lock(&devlink_mutex);
-	list_for_each_entry(devlink, &devlink_list, list) {
-		mutex_lock(&devlink->lock);
-		list_for_each_entry(devlink_port, &devlink->port_list, list) {
-			if (devlink_port->type == DEVLINK_PORT_TYPE_ETH &&
-			    devlink_port->type_dev == dev) {
-				__devlink_compat_running_version(devlink,
-								 buf, len);
-				mutex_unlock(&devlink->lock);
-				goto out;
-			}
-		}
-		mutex_unlock(&devlink->lock);
-	}
-out:
+	devlink = netdev_to_devlink(dev);
+	if (!devlink || !devlink->ops->info_get)
+		goto unlock_list;
+
+	mutex_lock(&devlink->lock);
+	__devlink_compat_running_version(devlink, buf, len);
+	mutex_unlock(&devlink->lock);
+unlock_list:
 	mutex_unlock(&devlink_mutex);
+
+	rtnl_lock();
+	dev_put(dev);
 }
 
 int devlink_compat_flash_update(struct net_device *dev, const char *file_name)
 {
-	struct devlink_port *devlink_port;
 	struct devlink *devlink;
+	int ret = -EOPNOTSUPP;
 
-	mutex_lock(&devlink_mutex);
-	list_for_each_entry(devlink, &devlink_list, list) {
-		mutex_lock(&devlink->lock);
-		list_for_each_entry(devlink_port, &devlink->port_list, list) {
-			int ret = -EOPNOTSUPP;
+	dev_hold(dev);
+	rtnl_unlock();
 
-			if (devlink_port->type != DEVLINK_PORT_TYPE_ETH ||
-			    devlink_port->type_dev != dev)
-				continue;
+	mutex_lock(&devlink_mutex);
+	devlink = netdev_to_devlink(dev);
+	if (!devlink || !devlink->ops->flash_update)
+		goto unlock_list;
 
-			mutex_unlock(&devlink_mutex);
-			if (devlink->ops->flash_update)
-				ret = devlink->ops->flash_update(devlink,
-								 file_name,
-								 NULL, NULL);
-			mutex_unlock(&devlink->lock);
-			return ret;
-		}
-		mutex_unlock(&devlink->lock);
-	}
+	mutex_lock(&devlink->lock);
+	ret = devlink->ops->flash_update(devlink, file_name, NULL, NULL);
+	mutex_unlock(&devlink->lock);
+unlock_list:
 	mutex_unlock(&devlink_mutex);
 
-	return -EOPNOTSUPP;
-}
+	rtnl_lock();
+	dev_put(dev);
 
-static int __init devlink_module_init(void)
-{
-	return genl_register_family(&devlink_nl_family);
+	return ret;
 }
 
-static void __exit devlink_module_exit(void)
+static int __init devlink_init(void)
 {
-	genl_unregister_family(&devlink_nl_family);
+	return genl_register_family(&devlink_nl_family);
 }
 
-module_init(devlink_module_init);
-module_exit(devlink_module_exit);
-
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
-MODULE_DESCRIPTION("Network physical device Netlink interface");
-MODULE_ALIAS_GENL_FAMILY(DEVLINK_GENL_NAME);
+subsys_initcall(devlink_init);

net/core/ethtool.c

@@ -805,11 +805,9 @@ static noinline_for_stack int ethtool_get_drvinfo(struct net_device *dev,
 	if (ops->get_eeprom_len)
 		info.eedump_len = ops->get_eeprom_len(dev);
 
-	rtnl_unlock();
 	if (!info.fw_version[0])
 		devlink_compat_running_version(dev, info.fw_version,
 					       sizeof(info.fw_version));
-	rtnl_lock();
 
 	if (copy_to_user(useraddr, &info, sizeof(info)))
 		return -EFAULT;
@@ -2040,15 +2038,8 @@ static noinline_for_stack int ethtool_flash_device(struct net_device *dev,
 		return -EFAULT;
 	efl.data[ETHTOOL_FLASH_MAX_FILENAME - 1] = 0;
 
-	if (!dev->ethtool_ops->flash_device) {
-		int ret;
-
-		rtnl_unlock();
-		ret = devlink_compat_flash_update(dev, efl.data);
-		rtnl_lock();
-
-		return ret;
-	}
+	if (!dev->ethtool_ops->flash_device)
+		return devlink_compat_flash_update(dev, efl.data);
 
 	return dev->ethtool_ops->flash_device(dev, &efl);
 }

net/dsa/Kconfig

@@ -6,7 +6,7 @@ config HAVE_NET_DSA
 
 config NET_DSA
 	tristate "Distributed Switch Architecture"
-	depends on HAVE_NET_DSA && MAY_USE_DEVLINK
+	depends on HAVE_NET_DSA
 	depends on BRIDGE || BRIDGE=n
 	select NET_SWITCHDEV
 	select PHYLINK