From nobody Mon Apr 6 12:09:16 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 3ABEEC32771 for ; Mon, 26 Sep 2022 07:18:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233264AbiIZHSR (ORCPT ); Mon, 26 Sep 2022 03:18:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233214AbiIZHSN (ORCPT ); Mon, 26 Sep 2022 03:18:13 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A80A82EF07 for ; Mon, 26 Sep 2022 00:18:11 -0700 (PDT) Received: from dggpeml500024.china.huawei.com (unknown [172.30.72.55]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4MbYs057hkz1P71t; Mon, 26 Sep 2022 15:13:56 +0800 (CST) Received: from dggpeml100012.china.huawei.com (7.185.36.121) by dggpeml500024.china.huawei.com (7.185.36.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 26 Sep 2022 15:18:09 +0800 Received: from localhost.localdomain (10.67.175.61) by dggpeml100012.china.huawei.com (7.185.36.121) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 26 Sep 2022 15:18:09 +0800 From: Zheng Yejian To: , , CC: Subject: [PATCH] ftrace: Properly unset FTRACE_HASH_FL_MOD Date: Mon, 26 Sep 2022 15:20:08 +0000 Message-ID: <20220926152008.2239274-1-zhengyejian1@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.67.175.61] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml100012.china.huawei.com (7.185.36.121) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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. Cc: stable@vger.kernel.org Fixes: 8c08f0d5c6fb ("ftrace: Have cached module filters be an active filte= r") Signed-off-by: Zheng Yejian --- 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 2.25.1