diff --git a/include/proto/connection.h b/include/proto/connection.h
index 88c7e50e5..02f3234a8 100644
--- a/include/proto/connection.h
+++ b/include/proto/connection.h
@@ -64,6 +64,8 @@ int conn_sock_drain(struct connection *conn);
 int conn_send_socks4_proxy_request(struct connection *conn);
 int conn_recv_socks4_proxy_response(struct connection *conn);
 
+__decl_hathreads(extern HA_SPINLOCK_T toremove_lock[MAX_THREADS]);
+
 /* returns true is the transport layer is ready */
 static inline int conn_xprt_ready(const struct connection *conn)
 {
@@ -595,7 +597,9 @@ static inline void conn_free(struct connection *conn)
 	}
 
 	conn_force_unsubscribe(conn);
+	HA_SPIN_LOCK(OTHER_LOCK, &toremove_lock[tid]);
 	LIST_DEL_LOCKED(&conn->list);
+	HA_SPIN_UNLOCK(OTHER_LOCK, &toremove_lock[tid]);
 	pool_free(pool_head_connection, conn);
 }
 
diff --git a/src/server.c b/src/server.c
index 02fa2a46c..a815f4001 100644
--- a/src/server.c
+++ b/src/server.c
@@ -66,6 +66,7 @@ struct eb_root idle_conn_srv = EB_ROOT;
 struct task *idle_conn_task = NULL;
 struct task *idle_conn_cleanup[MAX_THREADS] = { NULL };
 struct list toremove_connections[MAX_THREADS];
+__decl_hathreads(HA_SPINLOCK_T toremove_lock[MAX_THREADS]);
 
 /* The server names dictionary */
 struct dict server_name_dict = {
@@ -5660,6 +5661,7 @@ struct task *srv_cleanup_idle_connections(struct task *task, void *context, unsi
 			int j;
 			int did_remove = 0;
 
+			HA_SPIN_LOCK(OTHER_LOCK, &toremove_lock[i]);
 			for (j = 0; j < max_conn; j++) {
 				struct connection *conn = LIST_POP_LOCKED(&srv->idle_orphan_conns[i], struct connection *, list);
 				if (!conn)
@@ -5667,6 +5669,7 @@ struct task *srv_cleanup_idle_connections(struct task *task, void *context, unsi
 				did_remove = 1;
 				LIST_ADDQ_LOCKED(&toremove_connections[i], &conn->list);
 			}
+			HA_SPIN_UNLOCK(OTHER_LOCK, &toremove_lock[i]);
 			if (did_remove && max_conn < srv->curr_idle_thr[i])
 				srv_is_empty = 0;
 			if (did_remove)