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 B0E54C43334 for ; Mon, 20 Jun 2022 11:02:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241209AbiFTLCJ (ORCPT ); Mon, 20 Jun 2022 07:02:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241148AbiFTLCI (ORCPT ); Mon, 20 Jun 2022 07:02:08 -0400 Received: from mail-ed1-x536.google.com (mail-ed1-x536.google.com [IPv6:2a00:1450:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 861C66339 for ; Mon, 20 Jun 2022 04:02:07 -0700 (PDT) Received: by mail-ed1-x536.google.com with SMTP id z7so14552648edm.13 for ; Mon, 20 Jun 2022 04:02:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=WhQKcQWdfh+qi9q/v/2cFx1cfDj+vsZNcur6hEkr1L4=; b=ZTSGOyoo4P4+63u2AcFSC2wLm3VOxozGvCOgQPHMzOikglfXqQm8kRmi9oEe+TrT6D tVG2mNpE+z9eDC32vjWpPagDUbCraBzQhEs9bvUuBm2CmrxzKLDAcvttoEQ0wxhkSwUA C+ieD5sTF3SRcYeaEkNePDspxZsKsC2X9yI9wgzGY38zS6XY3T10wJiUpn3b99x2mQft wz9Aelb19XScjKQ006skw9xP5kP+XfSwHRT5puceRNWKHk7kvd1Ho8loLI5i6rMoAoPm WO1Y/cAzvBZqj/Us4cE1B7Rb/j6Si21Twu7c9XD5LkbdOAZEqK7PBWa009iAYQcvOHpN Q4zg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=WhQKcQWdfh+qi9q/v/2cFx1cfDj+vsZNcur6hEkr1L4=; b=SomeE8y6YAnTnp1TLmhATL37Nfnq37bHElUuNCRq/EPcvB4GlKSemOk2/nYpDXZR2V E/V3TED289z6Z9c4vaDDK2qjwTNO694l5H0Chc3y+26NbJM/J+qIAd3LJgTQKpWTAg5U fnUks4gGFt2yrJ7OPnx5xYCF5ggEd3TBFwd8Wi2TCuPZ1QRP6t41gPKGpwnSpO9t+XGt g2dyXufSYZQtPKQFk/oGdnaqeik+uE0WTYChmizfhgg/y7+cM8qLlRZLX71KKS/2TqUR uUFhweB/KrIFZMwKV6oIwwC5mmtUNpenDZMxqdQ1W0y9yWGe7e6pmmeEgsdPwwlnbTf4 oo1Q== X-Gm-Message-State: AJIora+AkNNSnEal3dhMtstsfxEJ9giM4KCwv3AISBLAUgzqADu0TXTb O7/G6YCsUU4YMYbk/9qGQkxKpDreNG3EgCzUcNM= X-Google-Smtp-Source: AGRyM1sgmWmoe2JqOoQ8RHXev39j0YYhnWlXRZK4mL4db2WGtm0Ur6rf/pZNYRr4yJv4St+pxXyeGIJLvICniUEp8b4= X-Received: by 2002:a05:6402:4390:b0:42e:b7e:e9ac with SMTP id o16-20020a056402439000b0042e0b7ee9acmr29054633edc.97.1655722926065; Mon, 20 Jun 2022 04:02:06 -0700 (PDT) MIME-Version: 1.0 References: <20220619204949.50d9154d@thinkpad> <20220620120234.5a65ac97@thinkpad> <20220620122904.30c06c4e@thinkpad> In-Reply-To: <20220620122904.30c06c4e@thinkpad> From: Andy Shevchenko Date: Mon, 20 Jun 2022 13:01:28 +0200 Message-ID: Subject: Re: Boot stall regression from "printk for 5.19" merge To: =?UTF-8?B?TWFyZWsgQmVow7pu?= , =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= Cc: Sergey Senozhatsky , John Ogness , Petr Mladek , Linus Torvalds , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org +Cc: Ilpo, a new maintainer for the driver On Mon, Jun 20, 2022 at 12:46 PM Marek Beh=C3=BAn wrote: > > On Mon, 20 Jun 2022 19:13:37 +0900 > Sergey Senozhatsky wrote: > > > On (22/06/20 12:02), Marek Beh=C3=BAn wrote: > > > > On (22/06/19 20:49), Marek Beh=C3=BAn wrote: > > > > [..] > > > > > causes a regression on arm64 (Marvell CN9130-CRB board) where the > > > > > system boot freezes in most cases (and is unusable until restarte= d by > > > > > watchdog), or, in some cases boots, but the console output gets m= angled > > > > > for a while (the serial console spits garbage characters). > > > > > > > > Can you please try disabling console kthreads and see how the boot > > > > process goes? Just `return 0` from printk_activate_kthreads() (I th= ink > > > > this should do the trick). > > > > > > This indeed makes the problem go away... > > > > Oh... OK. Didn't expect that :) > > > > > > > The garbage example: > > > > > > > > > > ... > > > > > [ 0.920951] raid6: using neon recovery algorithm > > > > > [ 0.921228] iommu: Default domain type: Translated > > > > > % > > > > > > > > > > gb@k+cFL/[ 4.954974] DSA: tree 0 setup > > > > > [ 4.955286] cfg80211: Loading compiled-in X.509 certificates= for regulatory database > > > > > > > > This is pretty suspicious. I don't see how console kthreads would > > > > corrupt the output. I suspect that something else is going on, some > > > > memory corruption, etc. > > > > > > Maybe multiple threads are writing to serial registers, or something.= .. > > > > That's possible. Console drivers usually should grab port->lock for > > write(), but maybe something is missing in the driver you use. What > > console driver are you using? > > compatible =3D "snps,dw-apb-uart", so drivers/tty/serial/8250/8250_dw.c > > seems that the function dw8250_serial_out() does not use the spinlock... > > Marek --=20 With Best Regards, Andy Shevchenko