tgupdate: merge remotes/origin/t/mptcp-drop-legacy-code onto t/mptcp-…

…drop-legacy-code base

.topdeps

@@ -0,0 +1 @@
+t/mptcp-drop-unneeded-argument

.topmsg

@@ -0,0 +1,12 @@
+From: Paolo Abeni <[email protected]>
+Subject: [PATCH] mptcp: drop legacy code
+
+After the previous commits the PM worker can't race anymore
+with the unaccepted subflow close and disposal, as the msk
+keeps a reference to such subflow.
+
+We can remove the now irrelevant and confusing checks explicitly
+preventing the mentioned race.
+
+Signed-off-by: Paolo Abeni <[email protected]>
+Reviewed-by: Matthieu Baerts <[email protected]>

net/mptcp/options.c

@@ -988,12 +988,7 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk,
 	mptcp_subflow_fully_established(subflow, mp_opt);
 
 check_notify:
-	/* if the subflow is not already linked into the conn_list, we can't
-	 * notify the PM: this subflow is still on the listener queue
-	 * and the PM possibly acquiring the subflow lock could race with
-	 * the listener close
-	 */
-	if (likely(subflow->pm_notified) || list_empty(&subflow->node))
+	if (likely(subflow->pm_notified))
 		return true;
 
 	subflow->pm_notified = 1;

net/mptcp/subflow.c

@@ -1871,11 +1871,10 @@ static void subflow_ulp_release(struct sock *ssk)
 
 	sk = ctx->conn;
 	if (sk) {
-		/* if the msk has been orphaned, keep the ctx
-		 * alive, will be freed by __mptcp_close_ssk(),
-		 * when the subflow is still unaccepted
+		/* if the subflow has been closed by the TCP stack, keep
+		 * the ctx alive, will be freed by __mptcp_close_ssk()
 		 */
-		release = ctx->disposable || list_empty(&ctx->node);
+		release = ctx->disposable;
 
 		/* inet_child_forget() does not call sk_state_change(),
 		 * explicitly trigger the socket close machinery