From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 E0461C43331 for ; Wed, 1 Apr 2020 16:54:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8F7C620719 for ; Wed, 1 Apr 2020 16:54:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585760082; bh=rOotCIjwWgz/HVtDMOKtKcP6oZ6IWtFte9or8xVoQg8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=p50BMKjn8SlRPcQx8/A6BAPI3tfnO9dlnlfY9+Ki36U6BLuYKG1jlQ6n0+6CZUYiF CfOwCvoGOC66sP4PFNDjPr8xBgPtUPxIYhakO8TT+HIWhc1qsmJm/iaxwiB4BEj707 6eT96LGcNO1/8fFa74yWwqAab5zwIo1G44GRBYyU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387790AbgDAQ1B (ORCPT ); Wed, 1 Apr 2020 12:27:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:51686 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387657AbgDAQ1A (ORCPT ); Wed, 1 Apr 2020 12:27:00 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8946A21582; Wed, 1 Apr 2020 16:26:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585758420; bh=rOotCIjwWgz/HVtDMOKtKcP6oZ6IWtFte9or8xVoQg8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qOCCEeZ13mD9XhATh8K5lgAb24QLgFJH36AeBTOh5R5Uz/mxc5mMkTEbqzvuuWVjC NfqF8eHKmvyRFphmhTdRUIFrNosolGIhpsdMbU2POIGFNP15xBrgRNH5twkP0yYNTt LrXQ+WRfXeoEiTw8FfAquKK9xGwltz/je8ASYzwM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jiri Kosina , "Steven Rostedt (VMware)" , Guenter Roeck Subject: [PATCH 4.19 046/116] ftrace/x86: Anotate text_mutex split between ftrace_arch_code_modify_post_process() and ftrace_arch_code_modify_prepare() Date: Wed, 1 Apr 2020 18:17:02 +0200 Message-Id: <20200401161548.389053638@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200401161542.669484650@linuxfoundation.org> References: <20200401161542.669484650@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jiri Kosina commit 074376ac0e1d1fcd4fafebca86ee6158e7c20680 upstream. ftrace_arch_code_modify_prepare() is acquiring text_mutex, while the corresponding release is happening in ftrace_arch_code_modify_post_process(). This has already been documented in the code, but let's also make the fact that this is intentional clear to the semantic analysis tools such as sparse. Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1906292321170.27227@cbobk.fhfr.pm Fixes: 39611265edc1a ("ftrace/x86: Add a comment to why we take text_mutex in ftrace_arch_code_modify_prepare()") Fixes: d5b844a2cf507 ("ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()") Signed-off-by: Jiri Kosina Signed-off-by: Steven Rostedt (VMware) Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/ftrace.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -35,6 +35,7 @@ #ifdef CONFIG_DYNAMIC_FTRACE int ftrace_arch_code_modify_prepare(void) + __acquires(&text_mutex) { mutex_lock(&text_mutex); set_kernel_text_rw(); @@ -43,6 +44,7 @@ int ftrace_arch_code_modify_prepare(void } int ftrace_arch_code_modify_post_process(void) + __releases(&text_mutex) { set_all_modules_text_ro(); set_kernel_text_ro();