From nobody Thu Sep 18 04:52:33 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68E45C4332F for ; Wed, 14 Dec 2022 14:02:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238570AbiLNOCZ (ORCPT ); Wed, 14 Dec 2022 09:02:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32848 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238524AbiLNOCL (ORCPT ); Wed, 14 Dec 2022 09:02:11 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3897320BC4 for ; Wed, 14 Dec 2022 06:02:11 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D189661A69 for ; Wed, 14 Dec 2022 14:02:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D0BDC4339E; Wed, 14 Dec 2022 14:02:10 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1p5SKn-000gun-13; Wed, 14 Dec 2022 09:02:09 -0500 Message-ID: <20221214140209.194205837@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 14 Dec 2022 09:01:38 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton Subject: [for-next][PATCH 5/8] tracing: Do not synchronize freeing of trigger filter on boot up References: <20221214140133.608431204@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Steven Rostedt (Google)" If a trigger filter on the kernel command line fails to apply (due to syntax error), it will be freed. The freeing will call tracepoint_synchronize_unregister(), but this is not needed during early boot up, and will even trigger a lockdep splat. Avoid calling the synchronization function when system_state is SYSTEM_BOOTING. Link: https://lore.kernel.org/linux-trace-kernel/20221213172429.7774f4ba@ga= ndalf.local.home Cc: Andrew Morton Acked-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_trigger.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_event= s_trigger.c index 19ce9d22bfd7..e535959939d3 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1085,8 +1085,14 @@ int set_trigger_filter(char *filter_str, rcu_assign_pointer(data->filter, filter); =20 if (tmp) { - /* Make sure the call is done with the filter */ - tracepoint_synchronize_unregister(); + /* + * Make sure the call is done with the filter. + * It is possible that a filter could fail at boot up, + * and then this path will be called. Avoid the synchronization + * in that case. + */ + if (system_state !=3D SYSTEM_BOOTING) + tracepoint_synchronize_unregister(); free_event_filter(tmp); } =20 --=20 2.35.1