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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_2 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 3F1A1C48BDF for ; Fri, 18 Jun 2021 16:25:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 25C28613BA for ; Fri, 18 Jun 2021 16:25:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235877AbhFRQ1y (ORCPT ); Fri, 18 Jun 2021 12:27:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:44100 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231898AbhFRQ1x (ORCPT ); Fri, 18 Jun 2021 12:27:53 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 033CD61260; Fri, 18 Jun 2021 16:25:42 +0000 (UTC) Date: Fri, 18 Jun 2021 12:25:41 -0400 From: Steven Rostedt To: Petr Mladek Cc: John Ogness , Sergey Senozhatsky , Thomas Gleixner , linux-kernel@vger.kernel.org, Stephen Rothwell , Andrew Morton , Peter Zijlstra , Daniel Bristot de Oliveira , Stephen Boyd , Alexander Potapenko Subject: Re: [PATCH next v4 1/2] lib/dump_stack: move cpu lock to printk.c Message-ID: <20210618122541.49fbd114@oasis.local.home> In-Reply-To: References: <20210617095051.4808-1-john.ogness@linutronix.de> <20210617095051.4808-2-john.ogness@linutronix.de> <20210617093243.795b4853@gandalf.local.home> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 18 Jun 2021 16:47:39 +0200 Petr Mladek wrote: > Good point! Just to be sure. Do you see the messed output with plain > kernel? Or do you need the extra patches (from Peter Zijlstra) that > redirect normal printk() to early_printk()? I sometimes use this with Peter's patches, which also do basically the same thing. > > My understanding is that early_printk() is used only for very early > boot message in plain kernel. And that there is not much concurrency > at that time. It will continue if you use ",keep" option. And that is something I have done without Peter's patches, but then they become illegible when there's a bug if more than one CPU triggers. > > That said. I always wanted to upstream Peter's patchset. But I never > found time to clean it up. That would be great too! -- Steve