diff --git a/Documentation/netlink/specs/mptcp_pm.yaml b/Documentation/netlink/specs/mptcp_pm.yaml
index 7e295ba..a670a9b 100644
--- a/Documentation/netlink/specs/mptcp_pm.yaml
+++ b/Documentation/netlink/specs/mptcp_pm.yaml
@@ -28,13 +28,13 @@
         traffic-patterns it can take a long time until the
         MPTCP_EVENT_ESTABLISHED is sent.
         Attributes: token, family, saddr4 | saddr6, daddr4 | daddr6, sport,
-        dport, server-side.
+        dport, server-side, [flags].
      -
       name: established
       doc: >-
         A MPTCP connection is established (can start new subflows).
         Attributes: token, family, saddr4 | saddr6, daddr4 | daddr6, sport,
-        dport, server-side.
+        dport, server-side, [flags].
      -
       name: closed
       doc: >-
diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h
index 67d015d..5fd5b4c 100644
--- a/include/uapi/linux/mptcp.h
+++ b/include/uapi/linux/mptcp.h
@@ -31,6 +31,8 @@
 #define MPTCP_INFO_FLAG_FALLBACK		_BITUL(0)
 #define MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED	_BITUL(1)
 
+#define MPTCP_PM_EV_FLAG_DENY_JOIN_ID0		_BITUL(0)
+
 #define MPTCP_PM_ADDR_FLAG_SIGNAL                      (1 << 0)
 #define MPTCP_PM_ADDR_FLAG_SUBFLOW                     (1 << 1)
 #define MPTCP_PM_ADDR_FLAG_BACKUP                      (1 << 2)
diff --git a/include/uapi/linux/mptcp_pm.h b/include/uapi/linux/mptcp_pm.h
index 6ac84b2f..7359d34 100644
--- a/include/uapi/linux/mptcp_pm.h
+++ b/include/uapi/linux/mptcp_pm.h
@@ -16,10 +16,10 @@
  *   good time to allocate memory and send ADD_ADDR if needed. Depending on the
  *   traffic-patterns it can take a long time until the MPTCP_EVENT_ESTABLISHED
  *   is sent. Attributes: token, family, saddr4 | saddr6, daddr4 | daddr6,
- *   sport, dport, server-side.
+ *   sport, dport, server-side, [flags].
  * @MPTCP_EVENT_ESTABLISHED: A MPTCP connection is established (can start new
  *   subflows). Attributes: token, family, saddr4 | saddr6, daddr4 | daddr6,
- *   sport, dport, server-side.
+ *   sport, dport, server-side, [flags].
  * @MPTCP_EVENT_CLOSED: A MPTCP connection has stopped. Attribute: token.
  * @MPTCP_EVENT_ANNOUNCED: A new address has been announced by the peer.
  *   Attributes: token, rem_id, family, daddr4 | daddr6 [, dport].
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index b763729..463c2e7 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -2211,6 +2211,7 @@ static int mptcp_event_created(struct sk_buff *skb,
 			       const struct sock *ssk)
 {
 	int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token));
+	u16 flags = 0;
 
 	if (err)
 		return err;
@@ -2218,6 +2219,12 @@ static int mptcp_event_created(struct sk_buff *skb,
 	if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side)))
 		return -EMSGSIZE;
 
+	if (READ_ONCE(msk->pm.remote_deny_join_id0))
+		flags |= MPTCP_PM_EV_FLAG_DENY_JOIN_ID0;
+
+	if (flags && nla_put_u16(skb, MPTCP_ATTR_FLAGS, flags))
+		return -EMSGSIZE;
+
 	return mptcp_event_add_subflow(skb, ssk);
 }