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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 71A4AC43387 for ; Tue, 18 Dec 2018 10:48:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C86A217D8 for ; Tue, 18 Dec 2018 10:48:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="qM+T0J4p" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726600AbeLRKs0 (ORCPT ); Tue, 18 Dec 2018 05:48:26 -0500 Received: from merlin.infradead.org ([205.233.59.134]:36428 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726395AbeLRKsZ (ORCPT ); Tue, 18 Dec 2018 05:48:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=EMcmWvwcB5sS6oAoVht9CmCG7i+vKHiJrI4i5GmHuVQ=; b=qM+T0J4pTCyWKjhlQoarTl6fx Zv/RrVZz+BGMP7VU+18syzA1LMySuyr+L1zHGvn2QglLp6/yRCZqNbZrRIvKh89ti6ClFo5hbRz8+ z/PW0zDXPQQ6roi3xw9S0TC2VVB+NBWkKKWKQsJb2K7DudXVe3XZnbxW2nvX2wrXnmN37YI+xySWr JBQ+JiWnOdFmJ5Rwne1MqDDTbQwnqFwVO9jocNTJcucapVgVVXmZPLPzDUJ1x0flDBo0TuE+h2ObY E0UaqQpgg1dvCzhD8/92A6s9DWNYu2Rlc1VQ5bxuiQuScEORcdbxGVNDG2eMY/HFueegUbKBwBEUP CFnZrMTSQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gZCv8-0007Tl-TO; Tue, 18 Dec 2018 10:48:15 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 855862027E1A4; Tue, 18 Dec 2018 11:48:12 +0100 (CET) Date: Tue, 18 Dec 2018 11:48:12 +0100 From: Peter Zijlstra To: Sergey Senozhatsky Cc: Petr Mladek , Steven Rostedt , Borislav Petkov , Andrew Morton , linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: Re: [RFC][PATCH] printk: increase devkmsg write() ratelimit Message-ID: <20181218104812.GC15430@hirez.programming.kicks-ass.net> References: <20181218091842.4996-1-sergey.senozhatsky@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181218091842.4996-1-sergey.senozhatsky@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 18, 2018 at 06:18:42PM +0900, Sergey Senozhatsky wrote: > Hello, > > RFC > > A painful subject: > > I just noticed that stock systemd (no systemd debugging enabled) on my > x86 box write()-s during shutdown to devkmsg more than before, so old > devkmsg ratelimits do not apply: > > $ sudo journalctl -n 40000 -f | grep "kernel: printk: systemd-shutdow" > kernel: printk: systemd-shutdow: 35 output lines suppressed due to ratelimiting > kernel: printk: systemd-shutdow: 31 output lines suppressed due to ratelimiting > kernel: printk: systemd-shutdow: 35 output lines suppressed due to ratelimiting > kernel: printk: systemd-shutdow: 36 output lines suppressed due to ratelimiting > kernel: printk: systemd-shutdow: 36 output lines suppressed due to ratelimiting > kernel: printk: systemd-shutdow: 36 output lines suppressed due to ratelimiting > kernel: printk: systemd-shutdow: 36 output lines suppressed due to ratelimiting > kernel: printk: systemd-shutdow: 35 output lines suppressed due to ratelimiting > > I know that there is a "kernel.printk_devkmsg" interface; do we > expect every systemd-enabled distro to find that out and to tweak > kernel.printk_devkmsg or shall we change the default devkmsg > ratelimit instead? How about we complain to systemd instead?