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 0BF49C433EF for ; Mon, 20 Jun 2022 15:22:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243585AbiFTPWr (ORCPT ); Mon, 20 Jun 2022 11:22:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50846 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244263AbiFTPW3 (ORCPT ); Mon, 20 Jun 2022 11:22:29 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D54ABBC2 for ; Mon, 20 Jun 2022 08:16:34 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 91FEF1F8D4; Mon, 20 Jun 2022 15:16:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1655738193; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=BAf076vfoeBSZ+0dOc1abGr7gkrgPSBGJwYFEHWAqLI=; b=T0jLZ/PBg41vLpGxlChwCCZROZomyYvZnF0w7/gzTFTZUIoAKrOO3NMzdye7JuPmyDKCQJ ET73fl9HvcMQte+TPBXiaZO8WsnbxQEEMB81tqOCHLU2UTvQ7qVjR/wxIn/7MqCoQoRQDZ hnZCllNnLUJ+Llir7j70MosC7Xqscoo= Received: from suse.cz (unknown [10.100.208.146]) (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 6E5B92C141; Mon, 20 Jun 2022 15:16:33 +0000 (UTC) Date: Mon, 20 Jun 2022 17:16:33 +0200 From: Petr Mladek To: Marek =?iso-8859-1?Q?Beh=FAn?= Cc: Linus Torvalds , John Ogness , Linux Kernel Mailing List , Sergey Senozhatsky , Steven Rostedt , Andy Shevchenko , Rasmus Villemoes , Jan Kara , Peter Zijlstra Subject: Re: [PATCH] printk/console: Enable console kthreads only when there is no boot console left Message-ID: References: <20220619204949.50d9154d@thinkpad> <87r13kwawb.fsf@jogness.linutronix.de> <20220620112936.48fcb2a4@thinkpad> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 2022-06-20 17:14:30, Petr Mladek wrote: > The console kthreads uncovered several races in console drivers. > All problems were in situation when a console was being properly > initialized and registered while an early console, using the same > port, was being used. > > These problems are pretty hard to debug because they often result > into silent boot crashes. It would be nice to fix them but it > looks like a can of worms. > > Prevent these problems by delaying the use of console kthreads > after all early consoles are gone. It might later be optimized. > But let's close this can of worms with a big hammer for now > so that they do not break first impression on the kthreads > that solve other real problems. Marek, could you please try if this patch solves the problem for you? Best Regards, Petr