diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index ea5600b747cc..2b3992c5060e 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -671,7 +671,7 @@ extern unsigned int rxrpc_max_call_lifetime;
 extern struct kmem_cache *rxrpc_call_jar;
 
 struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *, unsigned long);
-struct rxrpc_call *rxrpc_alloc_call(gfp_t);
+struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *, gfp_t);
 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *,
 					 struct rxrpc_conn_parameters *,
 					 struct sockaddr_rxrpc *,
diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c
index cbd1701e813a..3028298ca561 100644
--- a/net/rxrpc/call_accept.c
+++ b/net/rxrpc/call_accept.c
@@ -94,7 +94,7 @@ static int rxrpc_service_prealloc_one(struct rxrpc_sock *rx,
 	/* Now it gets complicated, because calls get registered with the
 	 * socket here, particularly if a user ID is preassigned by the user.
 	 */
-	call = rxrpc_alloc_call(gfp);
+	call = rxrpc_alloc_call(rx, gfp);
 	if (!call)
 		return -ENOMEM;
 	call->flags |= (1 << RXRPC_CALL_IS_SERVICE);
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index fcdd6555a820..8a5a42e8ec23 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -55,6 +55,8 @@ static void rxrpc_call_timer_expired(unsigned long _call)
 		rxrpc_set_timer(call, rxrpc_timer_expired, ktime_get_real());
 }
 
+static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
+
 /*
  * find an extant server call
  * - called in process context with IRQs enabled
@@ -95,7 +97,7 @@ found_extant_call:
 /*
  * allocate a new call
  */
-struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
+struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp)
 {
 	struct rxrpc_call *call;
 
@@ -114,6 +116,14 @@ struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
 		goto nomem_2;
 
 	mutex_init(&call->user_mutex);
+
+	/* Prevent lockdep reporting a deadlock false positive between the afs
+	 * filesystem and sys_sendmsg() via the mmap sem.
+	 */
+	if (rx->sk.sk_kern_sock)
+		lockdep_set_class(&call->user_mutex,
+				  &rxrpc_call_user_mutex_lock_class_key);
+
 	setup_timer(&call->timer, rxrpc_call_timer_expired,
 		    (unsigned long)call);
 	INIT_WORK(&call->processor, &rxrpc_process_call);
@@ -150,7 +160,8 @@ nomem:
 /*
  * Allocate a new client call.
  */
-static struct rxrpc_call *rxrpc_alloc_client_call(struct sockaddr_rxrpc *srx,
+static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
+						  struct sockaddr_rxrpc *srx,
 						  gfp_t gfp)
 {
 	struct rxrpc_call *call;
@@ -158,7 +169,7 @@ static struct rxrpc_call *rxrpc_alloc_client_call(struct sockaddr_rxrpc *srx,
 
 	_enter("");
 
-	call = rxrpc_alloc_call(gfp);
+	call = rxrpc_alloc_call(rx, gfp);
 	if (!call)
 		return ERR_PTR(-ENOMEM);
 	call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
@@ -209,7 +220,7 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 
 	_enter("%p,%lx", rx, user_call_ID);
 
-	call = rxrpc_alloc_client_call(srx, gfp);
+	call = rxrpc_alloc_client_call(rx, srx, gfp);
 	if (IS_ERR(call)) {
 		release_sock(&rx->sk);
 		_leave(" = %ld", PTR_ERR(call));