From patchwork Wed Jul 28 15:29:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 12406191 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5342EC4320A for ; Wed, 28 Jul 2021 15:30:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3CA3A60F91 for ; Wed, 28 Jul 2021 15:30:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237361AbhG1PaI (ORCPT ); Wed, 28 Jul 2021 11:30:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:45154 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237349AbhG1PaD (ORCPT ); Wed, 28 Jul 2021 11:30:03 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0F6006100A; Wed, 28 Jul 2021 15:29:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627486201; bh=LeW+FpjWCoF8S7HB9VLImulpdbgkWfK0a1HfGP8n+lc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CiV6tlH5OfxKCUqxaXdXzGAW7XbuCa/yAB1XbhJyqqV/u/0J2v9CxNUazFj/B6GrP SJY/egihaxhDAIrFvTqIKLu91bg+XN5Qy0/rOvgCdLq4iLToyoeRyGRz6NvYS1KYJY cLaFHC8MhFrIFvpIvUo77ulIkzaG4hVXkhJN25Sev9BmjYJ4TbE3QKca8CvjqlQeFf rL4z6WcdgJ3Djuzt2YvChsQnzrLrTyqu8EKO07CB3JoqpZ0qdwsBfXznBByC1D/EMd h2VJ5IfpMYU+6a8IUitoo64Uay5p3vVTJ8omlSER9Dv/Un94pEjjriSKVnugdK9KbN xhm/wSUOZzeSg== From: Masami Hiramatsu To: X86 ML , Ingo Molnar Cc: Steven Rostedt , Josh Poimboeuf , Masami Hiramatsu , Daniel Xu , linux-kernel@vger.kernel.org, bpf@vger.kernel.org, kuba@kernel.org, mingo@redhat.com, ast@kernel.org, Thomas Gleixner , Borislav Petkov , Peter Zijlstra , kernel-team@fb.com, yhs@fb.com, linux-ia64@vger.kernel.org, Abhishek Sagar , Andrii Nakryiko , Joe Perches Subject: [PATCH -tip v3 4/6] kprobes: Add assertions for required lock Date: Thu, 29 Jul 2021 00:29:57 +0900 Message-Id: <162748619699.59465.2846200321698832302.stgit@devnote2> X-Mailer: git-send-email 2.25.1 In-Reply-To: <162748615977.59465.13262421617578791515.stgit@devnote2> References: <162748615977.59465.13262421617578791515.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Add assertions for required locks instead of comment it so that the lockdep can inspect locks automatically. Signed-off-by: Masami Hiramatsu --- kernel/kprobes.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index ad39eeaa4371..ec3d97fd8c6b 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -959,11 +959,13 @@ int proc_kprobes_optimization_handler(struct ctl_table *table, int write, } #endif /* CONFIG_SYSCTL */ -/* Put a breakpoint for a probe. Must be called with 'text_mutex' locked. */ +/* Put a breakpoint for a probe. */ static void __arm_kprobe(struct kprobe *p) { struct kprobe *_p; + lockdep_assert_held(&text_mutex); + /* Find the overlapping optimized kprobes. */ _p = get_optimized_kprobe((unsigned long)p->addr); if (unlikely(_p)) @@ -974,11 +976,13 @@ static void __arm_kprobe(struct kprobe *p) optimize_kprobe(p); /* Try to optimize (add kprobe to a list) */ } -/* Remove the breakpoint of a probe. Must be called with 'text_mutex' locked. */ +/* Remove the breakpoint of a probe. */ static void __disarm_kprobe(struct kprobe *p, bool reopt) { struct kprobe *_p; + lockdep_assert_held(&text_mutex); + /* Try to unoptimize */ unoptimize_kprobe(p, kprobes_all_disarmed); @@ -1047,12 +1051,13 @@ static struct ftrace_ops kprobe_ipmodify_ops __read_mostly = { static int kprobe_ipmodify_enabled; static int kprobe_ftrace_enabled; -/* Caller must lock 'kprobe_mutex' */ static int __arm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops, int *cnt) { int ret = 0; + lockdep_assert_held(&kprobe_mutex); + ret = ftrace_set_filter_ip(ops, (unsigned long)p->addr, 0, 0); if (WARN_ONCE(ret < 0, "Failed to arm kprobe-ftrace at %pS (error %d)\n", p->addr, ret)) return ret; @@ -1084,12 +1089,13 @@ static int arm_kprobe_ftrace(struct kprobe *p) ipmodify ? &kprobe_ipmodify_enabled : &kprobe_ftrace_enabled); } -/* Caller must lock 'kprobe_mutex'. */ static int __disarm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops, int *cnt) { int ret = 0; + lockdep_assert_held(&kprobe_mutex); + if (*cnt == 1) { ret = unregister_ftrace_function(ops); if (WARN(ret < 0, "Failed to unregister kprobe-ftrace (error %d)\n", ret)) @@ -1133,7 +1139,6 @@ static int prepare_kprobe(struct kprobe *p) return arch_prepare_kprobe(p); } -/* Arm a kprobe with 'text_mutex'. */ static int arm_kprobe(struct kprobe *kp) { if (unlikely(kprobe_ftrace(kp))) @@ -1148,7 +1153,6 @@ static int arm_kprobe(struct kprobe *kp) return 0; } -/* Disarm a kprobe with 'text_mutex'. */ static int disarm_kprobe(struct kprobe *kp, bool reopt) { if (unlikely(kprobe_ftrace(kp))) @@ -1691,12 +1695,13 @@ static int aggr_kprobe_disabled(struct kprobe *ap) return 1; } -/* Disable one kprobe: Make sure called under 'kprobe_mutex' is locked. */ static struct kprobe *__disable_kprobe(struct kprobe *p) { struct kprobe *orig_p; int ret; + lockdep_assert_held(&kprobe_mutex); + /* Get an original kprobe for return */ orig_p = __get_valid_kprobe(p); if (unlikely(orig_p == NULL))