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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 CE016C43387 for ; Mon, 14 Jan 2019 08:05:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A5AF20659 for ; Mon, 14 Jan 2019 08:05:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="EZP76Nlj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726525AbfANIF1 (ORCPT ); Mon, 14 Jan 2019 03:05:27 -0500 Received: from mail-pl1-f196.google.com ([209.85.214.196]:39485 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725837AbfANIF1 (ORCPT ); Mon, 14 Jan 2019 03:05:27 -0500 Received: by mail-pl1-f196.google.com with SMTP id 101so9790066pld.6 for ; Mon, 14 Jan 2019 00:05:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=bY1aju/l/yJhBDW89Mh+OJ46hM69EgIYswBOJAJzuaQ=; b=EZP76NljHM09Xm61B9Isnvl3BYyisgqFmN6J5hF7ameByS4MWzowCU2gLtHwPwAuja 5qHVBqDAWQ3/jO0j7ejNkg7XCmlqTU3LHOBnmIbilS1Q5l0s+avKOBJw1uEs029fmfXO 6f4RHmZVsVajilMMzUAAzbfq519mNxSFMJcD39FlSkOexdG4nMRGjvw9LEkLo8zg4VD9 04ufYi3/f+PrQ3NjnTZ6oMLP/arat9nj1up7XCxe3Xu+BHlgLP8vY04Wy5PveDZw++WW JAUeKUv0Khdr1PaAQwMmF9ehE9NJgIZh82KwNHjmZ0m3HD0+uBshQK8avFcrAUM/XTKh kFuA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=bY1aju/l/yJhBDW89Mh+OJ46hM69EgIYswBOJAJzuaQ=; b=Za4LGP6XBXKUOMraNPfHzxnnNziqBnT09+Equ8C+EPz7sa9lq0+ckUS9mNvbnXPHIY cL8R+ZRZ9xaTG8jlR1XHOmjOoeRcqEXcx6Y/4BjOEO62o/Q3tTjt34eKpLDVgXdSl20Y 2o7y0Hg4t1hdacExHoZmjfuxplQch9mKDo++NQ1jgqqN2GjwOA6hN8in8CPYx8zOwn+G wseC670EZYu/nHz/cU9Y66eWVALXqC6jEg4/F55l6ZdgbqjVjwQfXSMGOrvHE2EU/XIC /oUy8DJ6TPE++KV06aEtVdq+3rboRadM65Vd2UWB4wkQBVcnutDOhxS/MVbPbK8FdR8B PoGw== X-Gm-Message-State: AJcUukebvOCLshd/C1p2tvCok2KgbHFjcXM28+HSSCK5Au1u5ZZ9y4DE QaHsRC4K5LzKQeFj3OfS+ds= X-Google-Smtp-Source: ALg8bN762l+QgzzurajeOTMsjBkIQeCr0/guvHBohb6K0O8k8r7LyaFfxxGmFd7H1BCuLMsSNEBigw== X-Received: by 2002:a17:902:e28e:: with SMTP id cf14mr24796049plb.311.1547453126724; Mon, 14 Jan 2019 00:05:26 -0800 (PST) Received: from localhost ([175.223.2.252]) by smtp.gmail.com with ESMTPSA id s190sm121322970pfb.103.2019.01.14.00.05.24 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 14 Jan 2019 00:05:25 -0800 (PST) Date: Mon, 14 Jan 2019 17:05:22 +0900 From: Sergey Senozhatsky To: Petr Mladek Cc: Greg Kroah-Hartman , Jiri Slaby , Sergey Senozhatsky , Steven Rostedt , Sergey Senozhatsky , linux-kernel@vger.kernel.org Subject: Re: [RFC 3/3] sysrq: Warn about insufficient console_loglevel Message-ID: <20190114080522.GA433@jagdpanzerIV> References: <20190111162038.19771-1-pmladek@suse.com> <20190111162038.19771-4-pmladek@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190111162038.19771-4-pmladek@suse.com> User-Agent: Mutt/1.11.2 (2019-01-07) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (01/11/19 17:20), Petr Mladek wrote: > +static void warn_console(bool console_suppressed, > + int orig_log_level, > + struct sysrq_key_op *op_p) > +{ > + static int warned; > + > + if (warned) > + return; > + > + /* Do not warn when people are already setting loglevel via sysrq */ > + if (op_p->enable_mask & SYSRQ_ENABLE_LOG) { > + warned = 1; > + return; > + } > + > + if (console_suppressed) { > + pr_info("Messages filtered by console_loglevel (%d)%s\n", > + orig_log_level, > + sysrq_on_mask(SYSRQ_ENABLE_LOG) ? ", try SysRq+7" : ""); > + warned = 1; > + } > +} I understand the intent. Some comments: - Not all of sysrq handlers printk() data. There are some quiet handlers. E.g. sysrq_handle_unraw(). Having "Messages filtered by console_loglevel" can be confusing. - Not all sysrq handlers use INFO level. E.g. sync_inodes_sb()->WARN_ON()->pr_warn(). So once again there can be a "false positive" "Messages filtered" error, while in fact no messages would be filtered out. What do you think? -ss