From nobody Mon Apr 6 13:28:25 2026 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 8A774C07E9D for ; Tue, 27 Sep 2022 16:03:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232997AbiI0QDG (ORCPT ); Tue, 27 Sep 2022 12:03:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41180 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232447AbiI0QBr (ORCPT ); Tue, 27 Sep 2022 12:01:47 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9785C1EEE1; Tue, 27 Sep 2022 09:01:44 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id 1714CB81C66; Tue, 27 Sep 2022 16:01:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9328C433C1; Tue, 27 Sep 2022 16:01:41 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1odD2q-00G2ye-19; Tue, 27 Sep 2022 12:02:52 -0400 Message-ID: <20220927160251.950267059@goodmis.org> User-Agent: quilt/0.66 Date: Tue, 27 Sep 2022 12:02:36 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Daniel Bristot de Oliveira , , stable@vger.kernel.org, Zheng Yejian Subject: [for-next][PATCH 20/20] ftrace: Properly unset FTRACE_HASH_FL_MOD References: <20220927160216.349640304@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: Zheng Yejian When executing following commands like what document said, but the log "#### all functions enabled ####" was not shown as expect: 1. Set a 'mod' filter: $ echo 'write*:mod:ext3' > /sys/kernel/tracing/set_ftrace_filter 2. Invert above filter: $ echo '!write*:mod:ext3' >> /sys/kernel/tracing/set_ftrace_filter 3. Read the file: $ cat /sys/kernel/tracing/set_ftrace_filter By some debugging, I found that flag FTRACE_HASH_FL_MOD was not unset after inversion like above step 2 and then result of ftrace_hash_empty() is incorrect. Link: https://lkml.kernel.org/r/20220926152008.2239274-1-zhengyejian1@huawe= i.com Cc: Cc: stable@vger.kernel.org Fixes: 8c08f0d5c6fb ("ftrace: Have cached module filters be an active filte= r") Signed-off-by: Zheng Yejian Signed-off-by: Steven Rostedt (Google) --- kernel/trace/ftrace.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 439e2ab6905e..5a1ec7e1af33 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6081,8 +6081,12 @@ int ftrace_regex_release(struct inode *inode, struct= file *file) =20 if (filter_hash) { orig_hash =3D &iter->ops->func_hash->filter_hash; - if (iter->tr && !list_empty(&iter->tr->mod_trace)) - iter->hash->flags |=3D FTRACE_HASH_FL_MOD; + if (iter->tr) { + if (list_empty(&iter->tr->mod_trace)) + iter->hash->flags &=3D ~FTRACE_HASH_FL_MOD; + else + iter->hash->flags |=3D FTRACE_HASH_FL_MOD; + } } else orig_hash =3D &iter->ops->func_hash->notrace_hash; =20 --=20 2.35.1