Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 548 insertions, 0 deletions

diff --git a/net/mctp/device.c b/net/mctp/device.c
new file mode 100644
index 000000000..acb97b257
--- /dev/null
+++ b/net/mctp/device.c
@@ -0,0 +1,548 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Management Component Transport Protocol (MCTP) - device implementation.
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#include <linux/if_arp.h>
+#include <linux/if_link.h>
+#include <linux/mctp.h>
+#include <linux/netdevice.h>
+#include <linux/rcupdate.h>
+#include <linux/rtnetlink.h>
+
+#include <net/addrconf.h>
+#include <net/netlink.h>
+#include <net/mctp.h>
+#include <net/mctpdevice.h>
+#include <net/sock.h>
+
+struct mctp_dump_cb {
+	int h;
+	int idx;
+	size_t a_idx;
+};
+
+/* unlocked: caller must hold rcu_read_lock.
+ * Returned mctp_dev has its refcount incremented, or NULL if unset.
+ */
+struct mctp_dev *__mctp_dev_get(const struct net_device *dev)
+{
+	struct mctp_dev *mdev = rcu_dereference(dev->mctp_ptr);
+
+	/* RCU guarantees that any mdev is still live.
+	 * Zero refcount implies a pending free, return NULL.
+	 */
+	if (mdev)
+		if (!refcount_inc_not_zero(&mdev->refs))
+			return NULL;
+	return mdev;
+}
+
+/* Returned mctp_dev does not have refcount incremented. The returned pointer
+ * remains live while rtnl_lock is held, as that prevents mctp_unregister()
+ */
+struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev)
+{
+	return rtnl_dereference(dev->mctp_ptr);
+}
+
+static int mctp_addrinfo_size(void)
+{
+	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
+		+ nla_total_size(1) // IFA_LOCAL
+		+ nla_total_size(1) // IFA_ADDRESS
+		;
+}
+
+/* flag should be NLM_F_MULTI for dump calls */
+static int mctp_fill_addrinfo(struct sk_buff *skb,
+			      struct mctp_dev *mdev, mctp_eid_t eid,
+			      int msg_type, u32 portid, u32 seq, int flag)
+{
+	struct ifaddrmsg *hdr;
+	struct nlmsghdr *nlh;
+
+	nlh = nlmsg_put(skb, portid, seq,
+			msg_type, sizeof(*hdr), flag);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	hdr = nlmsg_data(nlh);
+	hdr->ifa_family = AF_MCTP;
+	hdr->ifa_prefixlen = 0;
+	hdr->ifa_flags = 0;
+	hdr->ifa_scope = 0;
+	hdr->ifa_index = mdev->dev->ifindex;
+
+	if (nla_put_u8(skb, IFA_LOCAL, eid))
+		goto cancel;
+
+	if (nla_put_u8(skb, IFA_ADDRESS, eid))
+		goto cancel;
+
+	nlmsg_end(skb, nlh);
+
+	return 0;
+
+cancel:
+	nlmsg_cancel(skb, nlh);
+	return -EMSGSIZE;
+}
+
+static int mctp_dump_dev_addrinfo(struct mctp_dev *mdev, struct sk_buff *skb,
+				  struct netlink_callback *cb)
+{
+	struct mctp_dump_cb *mcb = (void *)cb->ctx;
+	u32 portid, seq;
+	int rc = 0;
+
+	portid = NETLINK_CB(cb->skb).portid;
+	seq = cb->nlh->nlmsg_seq;
+	for (; mcb->a_idx < mdev->num_addrs; mcb->a_idx++) {
+		rc = mctp_fill_addrinfo(skb, mdev, mdev->addrs[mcb->a_idx],
+					RTM_NEWADDR, portid, seq, NLM_F_MULTI);
+		if (rc < 0)
+			break;
+	}
+
+	return rc;
+}
+
+static int mctp_dump_addrinfo(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct mctp_dump_cb *mcb = (void *)cb->ctx;
+	struct net *net = sock_net(skb->sk);
+	struct hlist_head *head;
+	struct net_device *dev;
+	struct ifaddrmsg *hdr;
+	struct mctp_dev *mdev;
+	int ifindex;
+	int idx = 0, rc;
+
+	hdr = nlmsg_data(cb->nlh);
+	// filter by ifindex if requested
+	ifindex = hdr->ifa_index;
+
+	rcu_read_lock();
+	for (; mcb->h < NETDEV_HASHENTRIES; mcb->h++, mcb->idx = 0) {
+		idx = 0;
+		head = &net->dev_index_head[mcb->h];
+		hlist_for_each_entry_rcu(dev, head, index_hlist) {
+			if (idx >= mcb->idx &&
+			    (ifindex == 0 || ifindex == dev->ifindex)) {
+				mdev = __mctp_dev_get(dev);
+				if (mdev) {
+					rc = mctp_dump_dev_addrinfo(mdev,
+								    skb, cb);
+					mctp_dev_put(mdev);
+					// Error indicates full buffer, this
+					// callback will get retried.
+					if (rc < 0)
+						goto out;
+				}
+			}
+			idx++;
+			// reset for next iteration
+			mcb->a_idx = 0;
+		}
+	}
+out:
+	rcu_read_unlock();
+	mcb->idx = idx;
+
+	return skb->len;
+}
+
+static void mctp_addr_notify(struct mctp_dev *mdev, mctp_eid_t eid, int msg_type,
+			     struct sk_buff *req_skb, struct nlmsghdr *req_nlh)
+{
+	u32 portid = NETLINK_CB(req_skb).portid;
+	struct net *net = dev_net(mdev->dev);
+	struct sk_buff *skb;
+	int rc = -ENOBUFS;
+
+	skb = nlmsg_new(mctp_addrinfo_size(), GFP_KERNEL);
+	if (!skb)
+		goto out;
+
+	rc = mctp_fill_addrinfo(skb, mdev, eid, msg_type,
+				portid, req_nlh->nlmsg_seq, 0);
+	if (rc < 0) {
+		WARN_ON_ONCE(rc == -EMSGSIZE);
+		goto out;
+	}
+
+	rtnl_notify(skb, net, portid, RTNLGRP_MCTP_IFADDR, req_nlh, GFP_KERNEL);
+	return;
+out:
+	kfree_skb(skb);
+	rtnl_set_sk_err(net, RTNLGRP_MCTP_IFADDR, rc);
+}
+
+static const struct nla_policy ifa_mctp_policy[IFA_MAX + 1] = {
+	[IFA_ADDRESS]		= { .type = NLA_U8 },
+	[IFA_LOCAL]		= { .type = NLA_U8 },
+};
+
+static int mctp_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
+			    struct netlink_ext_ack *extack)
+{
+	struct net *net = sock_net(skb->sk);
+	struct nlattr *tb[IFA_MAX + 1];
+	struct net_device *dev;
+	struct mctp_addr *addr;
+	struct mctp_dev *mdev;
+	struct ifaddrmsg *ifm;
+	unsigned long flags;
+	u8 *tmp_addrs;
+	int rc;
+
+	rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_mctp_policy,
+			 extack);
+	if (rc < 0)
+		return rc;
+
+	ifm = nlmsg_data(nlh);
+
+	if (tb[IFA_LOCAL])
+		addr = nla_data(tb[IFA_LOCAL]);
+	else if (tb[IFA_ADDRESS])
+		addr = nla_data(tb[IFA_ADDRESS]);
+	else
+		return -EINVAL;
+
+	/* find device */
+	dev = __dev_get_by_index(net, ifm->ifa_index);
+	if (!dev)
+		return -ENODEV;
+
+	mdev = mctp_dev_get_rtnl(dev);
+	if (!mdev)
+		return -ENODEV;
+
+	if (!mctp_address_unicast(addr->s_addr))
+		return -EINVAL;
+
+	/* Prevent duplicates. Under RTNL so don't need to lock for reading */
+	if (memchr(mdev->addrs, addr->s_addr, mdev->num_addrs))
+		return -EEXIST;
+
+	tmp_addrs = kmalloc(mdev->num_addrs + 1, GFP_KERNEL);
+	if (!tmp_addrs)
+		return -ENOMEM;
+	memcpy(tmp_addrs, mdev->addrs, mdev->num_addrs);
+	tmp_addrs[mdev->num_addrs] = addr->s_addr;
+
+	/* Lock to write */
+	spin_lock_irqsave(&mdev->addrs_lock, flags);
+	mdev->num_addrs++;
+	swap(mdev->addrs, tmp_addrs);
+	spin_unlock_irqrestore(&mdev->addrs_lock, flags);
+
+	kfree(tmp_addrs);
+
+	mctp_addr_notify(mdev, addr->s_addr, RTM_NEWADDR, skb, nlh);
+	mctp_route_add_local(mdev, addr->s_addr);
+
+	return 0;
+}
+
+static int mctp_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
+			    struct netlink_ext_ack *extack)
+{
+	struct net *net = sock_net(skb->sk);
+	struct nlattr *tb[IFA_MAX + 1];
+	struct net_device *dev;
+	struct mctp_addr *addr;
+	struct mctp_dev *mdev;
+	struct ifaddrmsg *ifm;
+	unsigned long flags;
+	u8 *pos;
+	int rc;
+
+	rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_mctp_policy,
+			 extack);
+	if (rc < 0)
+		return rc;
+
+	ifm = nlmsg_data(nlh);
+
+	if (tb[IFA_LOCAL])
+		addr = nla_data(tb[IFA_LOCAL]);
+	else if (tb[IFA_ADDRESS])
+		addr = nla_data(tb[IFA_ADDRESS]);
+	else
+		return -EINVAL;
+
+	/* find device */
+	dev = __dev_get_by_index(net, ifm->ifa_index);
+	if (!dev)
+		return -ENODEV;
+
+	mdev = mctp_dev_get_rtnl(dev);
+	if (!mdev)
+		return -ENODEV;
+
+	pos = memchr(mdev->addrs, addr->s_addr, mdev->num_addrs);
+	if (!pos)
+		return -ENOENT;
+
+	rc = mctp_route_remove_local(mdev, addr->s_addr);
+	// we can ignore -ENOENT in the case a route was already removed
+	if (rc < 0 && rc != -ENOENT)
+		return rc;
+
+	spin_lock_irqsave(&mdev->addrs_lock, flags);
+	memmove(pos, pos + 1, mdev->num_addrs - 1 - (pos - mdev->addrs));
+	mdev->num_addrs--;
+	spin_unlock_irqrestore(&mdev->addrs_lock, flags);
+
+	mctp_addr_notify(mdev, addr->s_addr, RTM_DELADDR, skb, nlh);
+
+	return 0;
+}
+
+void mctp_dev_hold(struct mctp_dev *mdev)
+{
+	refcount_inc(&mdev->refs);
+}
+
+void mctp_dev_put(struct mctp_dev *mdev)
+{
+	if (mdev && refcount_dec_and_test(&mdev->refs)) {
+		kfree(mdev->addrs);
+		dev_put(mdev->dev);
+		kfree_rcu(mdev, rcu);
+	}
+}
+
+void mctp_dev_release_key(struct mctp_dev *dev, struct mctp_sk_key *key)
+	__must_hold(&key->lock)
+{
+	if (!dev)
+		return;
+	if (dev->ops && dev->ops->release_flow)
+		dev->ops->release_flow(dev, key);
+	key->dev = NULL;
+	mctp_dev_put(dev);
+}
+
+void mctp_dev_set_key(struct mctp_dev *dev, struct mctp_sk_key *key)
+	__must_hold(&key->lock)
+{
+	mctp_dev_hold(dev);
+	key->dev = dev;
+}
+
+static struct mctp_dev *mctp_add_dev(struct net_device *dev)
+{
+	struct mctp_dev *mdev;
+
+	ASSERT_RTNL();
+
+	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
+	if (!mdev)
+		return ERR_PTR(-ENOMEM);
+
+	spin_lock_init(&mdev->addrs_lock);
+
+	mdev->net = mctp_default_net(dev_net(dev));
+
+	/* associate to net_device */
+	refcount_set(&mdev->refs, 1);
+	rcu_assign_pointer(dev->mctp_ptr, mdev);
+
+	dev_hold(dev);
+	mdev->dev = dev;
+
+	return mdev;
+}
+
+static int mctp_fill_link_af(struct sk_buff *skb,
+			     const struct net_device *dev, u32 ext_filter_mask)
+{
+	struct mctp_dev *mdev;
+
+	mdev = mctp_dev_get_rtnl(dev);
+	if (!mdev)
+		return -ENODATA;
+	if (nla_put_u32(skb, IFLA_MCTP_NET, mdev->net))
+		return -EMSGSIZE;
+	return 0;
+}
+
+static size_t mctp_get_link_af_size(const struct net_device *dev,
+				    u32 ext_filter_mask)
+{
+	struct mctp_dev *mdev;
+	unsigned int ret;
+
+	/* caller holds RCU */
+	mdev = __mctp_dev_get(dev);
+	if (!mdev)
+		return 0;
+	ret = nla_total_size(4); /* IFLA_MCTP_NET */
+	mctp_dev_put(mdev);
+	return ret;
+}
+
+static const struct nla_policy ifla_af_mctp_policy[IFLA_MCTP_MAX + 1] = {
+	[IFLA_MCTP_NET]		= { .type = NLA_U32 },
+};
+
+static int mctp_set_link_af(struct net_device *dev, const struct nlattr *attr,
+			    struct netlink_ext_ack *extack)
+{
+	struct nlattr *tb[IFLA_MCTP_MAX + 1];
+	struct mctp_dev *mdev;
+	int rc;
+
+	rc = nla_parse_nested(tb, IFLA_MCTP_MAX, attr, ifla_af_mctp_policy,
+			      NULL);
+	if (rc)
+		return rc;
+
+	mdev = mctp_dev_get_rtnl(dev);
+	if (!mdev)
+		return 0;
+
+	if (tb[IFLA_MCTP_NET])
+		WRITE_ONCE(mdev->net, nla_get_u32(tb[IFLA_MCTP_NET]));
+
+	return 0;
+}
+
+/* Matches netdev types that should have MCTP handling */
+static bool mctp_known(struct net_device *dev)
+{
+	/* only register specific types (inc. NONE for TUN devices) */
+	return dev->type == ARPHRD_MCTP ||
+		   dev->type == ARPHRD_LOOPBACK ||
+		   dev->type == ARPHRD_NONE;
+}
+
+static void mctp_unregister(struct net_device *dev)
+{
+	struct mctp_dev *mdev;
+
+	mdev = mctp_dev_get_rtnl(dev);
+	if (!mdev)
+		return;
+
+	RCU_INIT_POINTER(mdev->dev->mctp_ptr, NULL);
+
+	mctp_route_remove_dev(mdev);
+	mctp_neigh_remove_dev(mdev);
+
+	mctp_dev_put(mdev);
+}
+
+static int mctp_register(struct net_device *dev)
+{
+	struct mctp_dev *mdev;
+
+	/* Already registered? */
+	if (rtnl_dereference(dev->mctp_ptr))
+		return 0;
+
+	/* only register specific types */
+	if (!mctp_known(dev))
+		return 0;
+
+	mdev = mctp_add_dev(dev);
+	if (IS_ERR(mdev))
+		return PTR_ERR(mdev);
+
+	return 0;
+}
+
+static int mctp_dev_notify(struct notifier_block *this, unsigned long event,
+			   void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	int rc;
+
+	switch (event) {
+	case NETDEV_REGISTER:
+		rc = mctp_register(dev);
+		if (rc)
+			return notifier_from_errno(rc);
+		break;
+	case NETDEV_UNREGISTER:
+		mctp_unregister(dev);
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static int mctp_register_netdevice(struct net_device *dev,
+				   const struct mctp_netdev_ops *ops)
+{
+	struct mctp_dev *mdev;
+
+	mdev = mctp_add_dev(dev);
+	if (IS_ERR(mdev))
+		return PTR_ERR(mdev);
+
+	mdev->ops = ops;
+
+	return register_netdevice(dev);
+}
+
+int mctp_register_netdev(struct net_device *dev,
+			 const struct mctp_netdev_ops *ops)
+{
+	int rc;
+
+	rtnl_lock();
+	rc = mctp_register_netdevice(dev, ops);
+	rtnl_unlock();
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(mctp_register_netdev);
+
+void mctp_unregister_netdev(struct net_device *dev)
+{
+	unregister_netdev(dev);
+}
+EXPORT_SYMBOL_GPL(mctp_unregister_netdev);
+
+static struct rtnl_af_ops mctp_af_ops = {
+	.family = AF_MCTP,
+	.fill_link_af = mctp_fill_link_af,
+	.get_link_af_size = mctp_get_link_af_size,
+	.set_link_af = mctp_set_link_af,
+};
+
+static struct notifier_block mctp_dev_nb = {
+	.notifier_call = mctp_dev_notify,
+	.priority = ADDRCONF_NOTIFY_PRIORITY,
+};
+
+void __init mctp_device_init(void)
+{
+	register_netdevice_notifier(&mctp_dev_nb);
+
+	rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_GETADDR,
+			     NULL, mctp_dump_addrinfo, 0);
+	rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_NEWADDR,
+			     mctp_rtm_newaddr, NULL, 0);
+	rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_DELADDR,
+			     mctp_rtm_deladdr, NULL, 0);
+	rtnl_af_register(&mctp_af_ops);
+}
+
+void __exit mctp_device_exit(void)
+{
+	rtnl_af_unregister(&mctp_af_ops);
+	rtnl_unregister(PF_MCTP, RTM_DELADDR);
+	rtnl_unregister(PF_MCTP, RTM_NEWADDR);
+	rtnl_unregister(PF_MCTP, RTM_GETADDR);
+
+	unregister_netdevice_notifier(&mctp_dev_nb);
+}