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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 328BBC43334 for ; Mon, 20 Jun 2022 11:47:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241198AbiFTLrp (ORCPT ); Mon, 20 Jun 2022 07:47:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35896 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235408AbiFTLrn (ORCPT ); Mon, 20 Jun 2022 07:47:43 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33AC465D1 for ; Mon, 20 Jun 2022 04:47:42 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id E5ACF1FD99; Mon, 20 Jun 2022 11:47:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1655725660; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=96v5KVBMCRN0CUZgfk6RU0ZTFsFKM6nbaz5uskmEPVk=; b=e5FAVZ6ebvJIKU0QIKQTrIBY2XCb2PpMgiBdrZMl3DtvavI4S2wsClKp9rxhXZGlV0HkUp RuZufOChROY3avKns7frOhIQOZ1XicY41Ry0V6zZnG7+81pt/j14tWdn6HCoXE0Bn57LAx 2eQ7l+SFnOeg9XQNCYaOnCLakQKAAAg= Received: from suse.cz (unknown [10.100.201.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id B8BEC2C15D; Mon, 20 Jun 2022 11:47:40 +0000 (UTC) Date: Mon, 20 Jun 2022 13:47:40 +0200 From: Petr Mladek To: Marek =?iso-8859-1?Q?Beh=FAn?= Cc: John Ogness , Ilpo =?iso-8859-1?Q?J=E4rvinen?= , Linus Torvalds , linux-kernel@vger.kernel.org, Sergey Senozhatsky , Steven Rostedt , Andy Shevchenko , Rasmus Villemoes , Jan Kara , Peter Zijlstra Subject: Re: Boot stall regression from "printk for 5.19" merge Message-ID: References: <20220619204949.50d9154d@thinkpad> <87r13kwawb.fsf@jogness.linutronix.de> <20220620112936.48fcb2a4@thinkpad> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Resending with Ilpo, driver maintainer, in CC. On Mon 2022-06-20 13:44:17, Petr Mladek wrote: > On Mon 2022-06-20 11:29:36, Marek Behún wrote: > > On Mon, 20 Jun 2022 00:29:16 +0206 > > John Ogness wrote: > > > On 2022-06-19, Marek Behún wrote: > > > > causes a regression on arm64 (Marvell CN9130-CRB board) where the > > > > system boot freezes in most cases (and is unusable until restarted by > > > > watchdog), or, in some cases boots, but the console output gets mangled > > > > for a while (the serial console spits garbage characters). > > > > attaching bootlogs and config. > > This is the log when the system booted: > > > [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd083] > > [ 0.000000] Linux version 5.19.0-rc2-00410-g9776fe0f424b (kabel@dellmb) (aarch64-unknown-linux-gnu-gcc (Gentoo Hardened 10.3.1_p20211126 p0) 10.3.1 20211126, GNU ld (Gentoo 2.37_p1 p2) 2.37) #491 SMP Mon Jun 20 11:00:54 CEST 2022 > > [ 0.000000] Machine model: Marvell Armada CN9130-CRB-B > > [ 0.000000] earlycon: uart8250 at MMIO32 0x00000000f0512000 (options '') > > [ 0.000000] printk: bootconsole [uart8250] enabled > > Early console enabled. > > > [ 0.000000] NUMA: No NUMA configuration found > [...] > > [ 0.062565] rcu: Hierarchical SRCU implementation. > > [ 0.062589] printk: bootconsole [uart8250] printing thread started > > The early console started being handled by the kthread. > > > [ 0.073843] smp: Bringing up secondary CPUs ... > > [ 0.074238] Detected PIPT I-cache on CPU1 > [...] > > [ 1.067359] io scheduler kyber registered > > [ 1.120214] armada-ap806-pinctrl f06f4000.system-controller:pinctrl: registered pinctrl driver > > [ 1.120577] armada-cp110-pinctrl f2440000.system-controller:pinctrl: registered pinctrl driver > > [ 1.137980] mv_xor_v2 f0400000.xor: Marvell Version 2 XOR driver > > [ 1.166562] printk:[ console [ttyS0] printing thread started > > [ 1.166564] printk: console [ttyS0] enabled > > 2nd console was added using the properly initialized serial port. > It should use the same physical port as the early console. > > Both early console and proper console driver has its own kthread. > > > 1.166486] f0512000.serial: ttyS0 at MMIO 0xf0512000 (irq = 22, base_baud = 12500000) is a 16550A > > The line is malformed. I wonder if both early console and proper > console used the same port in parallel. > > > [ 1.166567] printk: bootconsole [uart8250] disabled > > [ 1.185422] printk: bootconsole [uart8250] printing thread stopped > > The early console was disabled. Only the properly initialized serial > console is used. All should be fine now. > > > > [ 1.188773] brd: module loaded > > [ 1.190567] loop: module loaded > [...] > > [ 5.316958] Freeing unused kernel memory: 2752K > > [ 5.364349] Run /sbin/init as init process > > And I did not catch any further problem. > > So, it looks like that con->write() code is not correctly serialized > between the early and normal console. > > > Now, let's see the last lines of failing logs: > > > > [ 1.071214] io scheduler kyber registered > > [ 1.124272] armada-ap806-pinctrl f06f4000.system-controller:pinctrl: registered pinctrl driver > > [ > > > [ 1.067314] io scheduler kyber registered > > [ 1.120226] armada-ap806-pinctrl f06f4000.system-controller:pinctrl: registered pinctrl driver > > [ 1.120603] armada-cp110-pinctrl f2440000.system-controller:pinctrl: registered pinctrl driver > > [ 1.137975] mv_xor_v2 f0400000.xor: Marvell Version 2 XOR driver > > [ 1.138248] mv_xor_v2 f0420000.xor: Marvell Version 2 XOR driver > > [ 1. > > > [ 1.067214] io scheduler kyber registered > > [ 1.120098] armada-ap806-pinctrl f06f4000.system-controller:pinctrl: registered pinctrl driver > > [ 1.120466] armada-cp110-pinctrl f2440000.system-controller:pinctrl: registered pinctrl driver > > [ 1.137871] mv_xor_v2 f0400000.xor: Marvell Version 2 XOR driver > > [ 1.138160] mv_xor_v2 f0420000.xor: Marvell Version 2 XOR driver > > [ > > All three logs end in the middle of a line. If you compare it with the > "working" log then the end 1-3 lines before the normal console was added. > > The console output might is delayed because of the threads. Most > likely, the output ended when both early and normal console driver > started to use the same port. > > I am going to check the driver... > > Best Regards, > Petr