--- zzzz-none-000/linux-4.1.52/net/core/sock.c	2018-05-28 02:26:45.000000000 +0000
+++ bcm63-7530ax-731/linux-4.1.52/net/core/sock.c	2022-03-02 11:37:13.000000000 +0000
@@ -136,6 +136,13 @@
 
 #include <trace/events/sock.h>
 
+#if defined(CONFIG_BCM_MPTCP) && defined(CONFIG_BCM_KF_MPTCP)
+#ifdef CONFIG_MPTCP
+#include <net/mptcp.h>
+#include <net/inet_common.h>
+#endif
+
+#endif
 #include <net/tcp.h>
 #include <net/busy_poll.h>
 
@@ -277,7 +284,11 @@
   "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
   "slock-AF_NFC"   , "slock-AF_VSOCK"    ,"slock-AF_MAX"
 };
+#if !defined(CONFIG_BCM_MPTCP) || !defined(CONFIG_BCM_KF_MPTCP)
 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
+#else
+char *const af_family_clock_key_strings[AF_MAX+1] = {
+#endif
   "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
   "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
   "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
@@ -298,7 +309,11 @@
  * sk_callback_lock locking rules are per-address-family,
  * so split the lock classes by using a per-AF key:
  */
+#if !defined(CONFIG_BCM_MPTCP) || !defined(CONFIG_BCM_KF_MPTCP)
 static struct lock_class_key af_callback_keys[AF_MAX];
+#else
+struct lock_class_key af_callback_keys[AF_MAX];
+#endif
 
 /* Take into consideration the size of the struct sk_buff overhead in the
  * determination of these values, since that is non-constant across
@@ -1265,8 +1280,30 @@
  *
  * (We also register the sk_lock with the lock validator.)
  */
+#if !defined(CONFIG_BCM_MPTCP) || !defined(CONFIG_BCM_KF_MPTCP)
 static inline void sock_lock_init(struct sock *sk)
 {
+#else
+void sock_lock_init(struct sock *sk)
+{
+#ifdef CONFIG_MPTCP
+	/* Reclassify the lock-class for subflows */
+	if (sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP)
+		if (mptcp(tcp_sk(sk)) || tcp_sk(sk)->is_master_sk) {
+			sock_lock_init_class_and_name(sk, "slock-AF_INET-MPTCP",
+						      &meta_slock_key,
+						      "sk_lock-AF_INET-MPTCP",
+						      &meta_key);
+
+			/* We don't yet have the mptcp-point.
+			 * Thus we still need inet_sock_destruct
+			 */
+			sk->sk_destruct = inet_sock_destruct;
+			return;
+		}
+#endif
+
+#endif
 	sock_lock_init_class_and_name(sk,
 			af_family_slock_key_strings[sk->sk_family],
 			af_family_slock_keys + sk->sk_family,
@@ -1313,7 +1350,11 @@
 }
 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
 
+#if !defined(CONFIG_BCM_MPTCP) || !defined(CONFIG_BCM_KF_MPTCP)
 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
+#else
+struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
+#endif
 		int family)
 {
 	struct sock *sk;
@@ -1534,6 +1575,9 @@
 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
 
 		sock_reset_flag(newsk, SOCK_DONE);
+#if defined(CONFIG_BCM_MPTCP) && defined(CONFIG_BCM_KF_MPTCP)
+		sock_reset_flag(newsk, SOCK_MPTCP);
+#endif
 		skb_queue_head_init(&newsk->sk_error_queue);
 
 		filter = rcu_dereference_protected(newsk->sk_filter, 1);