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=-5.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 20EC3C433E0 for ; Thu, 7 Jan 2021 17:59:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9991223E8 for ; Thu, 7 Jan 2021 17:59:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728240AbhAGR65 (ORCPT ); Thu, 7 Jan 2021 12:58:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728201AbhAGR65 (ORCPT ); Thu, 7 Jan 2021 12:58:57 -0500 Received: from mail-pf1-x42f.google.com (mail-pf1-x42f.google.com [IPv6:2607:f8b0:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CBD30C0612F5; Thu, 7 Jan 2021 09:58:16 -0800 (PST) Received: by mail-pf1-x42f.google.com with SMTP id h10so4322184pfo.9; Thu, 07 Jan 2021 09:58:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:subject:to:cc:newsgroups:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=hTkzqrCNdP0r0M/fUFV1DV/mK3Fh5BcFABP+peFArds=; b=qCvkVAW7GzxhEniptCfQUtsKyYzGgk5rW8/4bIz9sHBwE2Isgyhd8KBe6UAyM8Om/T sfbjGnIEXiGsEvsYfifeQBcslPMSQgo6d1CzPtsRE7jQhLkUSGNCqpkyK0T7/33ToOyP ZdNl89k8ISaTpcBjDLOPgP4J10ovwyXlIGNSdTQXUz3eJvZQiRU8j1snMV0JeOaVl/GZ ZTuoKvnaoyjtKBz4tMOaJL95TCMnBGbeUGrU35UnBUAVP0VNdzWfh0n6fFrtPbIbw4UJ yrXT19r8VLm8dP4Y+Pzr+xrDiew06eQvAElhECUmGZVZTfCgyx/AdVANdd6y5c8kJc8D zAIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:subject:to:cc:newsgroups:references:from :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=hTkzqrCNdP0r0M/fUFV1DV/mK3Fh5BcFABP+peFArds=; b=nnKQGFsYci/EdRNH7/zYH4/StZCEyRrsBDXm6+aNhX5mqTOcvkSq/A0Cme2ZnTGDv6 rDb/yFnRQ2KRs816pLkpdxYS61qKCo1DArj9NceYRrH5XpAXItNrTFIohABFNSqnLKRg OEGSaDhEW7Dzz0mNEXOZRGRk+jvLLWKBJL1139tyqC2NKVWiLd4EzohQdK338JTmrRlv Xpn6Yt19C/wbDfajgHWwOqciqmHb5k+VJ3bfM5nbnbAbjFdZmfxY4HkRy4ajpIFTbq63 PfNb0owkUyJqnem9oNdzei0r9A87WADAyj3Zm7OYWM6AGSmR9VMR654JC3spEGg9xHTX 7B6Q== X-Gm-Message-State: AOAM532JoNI0rqANNYMLdpRIaNT/0YNbzVAO5Ia1+JNr13RKBGbZKT9m a/Sev61kWyn1hE1O5bjSHjY= X-Google-Smtp-Source: ABdhPJzR/BNW8sCHTSftdbijHuVAAOcy+X7BgxMPUvq3C6Xv33E/J822bkKqzWyqjeNNDD3G1v/Ozw== X-Received: by 2002:aa7:93cf:0:b029:19d:e287:b02b with SMTP id y15-20020aa793cf0000b029019de287b02bmr9856835pff.66.1610042296286; Thu, 07 Jan 2021 09:58:16 -0800 (PST) Received: from [192.168.50.50] (c-24-4-73-83.hsd1.ca.comcast.net. [24.4.73.83]) by smtp.gmail.com with ESMTPSA id o193sm6623174pfg.27.2021.01.07.09.58.08 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 07 Jan 2021 09:58:09 -0800 (PST) Sender: Vineet Gupta Subject: Re: ARC no console output (was Re: [PATCH 1/2] init/console: Use ttynull as a fallback when there is no console) To: Petr Mladek Cc: John Ogness , Sergey Senozhatsky , Steven Rostedt , Linus Torvalds , Guenter Roeck , Shreyas Joshi , shreyasjoshi15@gmail.com, Greg Kroah-Hartman , Sergey Senozhatsky , linux-kernel@vger.kernel.org, buildroot@busybox.net, Thomas Petazzoni , linux-arch@vger.kernel.org, arcml Newsgroups: gmane.linux.kernel.cross-arch,gmane.linux.kernel,gmane.linux.kernel.arc References: <20201111135450.11214-1-pmladek@suse.com> <20201111135450.11214-2-pmladek@suse.com> <8735zdm86m.fsf@jogness.linutronix.de> <50ade852-c598-6476-1f4b-9a3f8d11d143@synopsys.com> From: Vineet Gupta Message-ID: <466644f5-bed7-caef-9fcd-e66208f65545@synopsys.com> Date: Thu, 7 Jan 2021 09:58:05 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org On 1/7/21 9:04 AM, Petr Mladek wrote: > On Thu 2021-01-07 08:43:16, Vineet Gupta wrote: >> Hi John, >> >> On 1/7/21 1:02 AM, John Ogness wrote: >>> Hi Vineet, >>> >>> On 2021-01-06, Vineet Gupta wrote: >>>> This breaks ARC booting (no output on console). >>> >>> Could you provide the kernel boot arguments that you use? This series is >>> partly about addressing users that have used boot arguments that are >>> technically incorrect (even if had worked). Seeing the boot arguments of >>> users that are not experiencing problems may help to reveal some of the >>> unusual console usages until now. >> >> >> Kernel command line: earlycon=uart8250,mmio32,0xf0005000,115200n8 >> console=ttyS0,115200n8 debug print-fatal-signals=1 > > This is strange, the problematic patch should use ttynull > only as a fallback. It should not be used when a particular console > is defined on the command line. What happens in my case is console_on_rootfs() doesn't find /dev/console and switching to ttynull. /dev is not present because devtmpfs doesn't automount for initramfs. > The only explanation would be that ttyS0 gets registered too late > and ttynull is added as a fallback in the meantime. I don't know if ttyS0 console should have registered already but even if it did - the /dev node missing would not have helped ? > > Anyway, I propose the revert the problematic patch for 5.11-rc3, > see > https://lore.kernel.org/lkml/20210107164400.17904-2-pmladek@suse.com/ > This mystery is a good reason to avoid bigger changes at this stage. > > Best Regards, > Petr >