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 D92F4C43334 for ; Mon, 13 Jun 2022 13:27:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377459AbiFMN1C (ORCPT ); Mon, 13 Jun 2022 09:27:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357425AbiFMNYx (ORCPT ); Mon, 13 Jun 2022 09:24:53 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96D4D6C0D8 for ; Mon, 13 Jun 2022 04:24:15 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 50D7C21CC7; Mon, 13 Jun 2022 11:24:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1655119454; 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=oVDyyQNRZdOpJs5Ykd60IDoqlaom7m+VsdjwLrey5C4=; b=l7TxDF/FRkFqe6u/FqVZiF7Ihqp5aGKfbXpdYa9J5gK2wPjMO7VFhYqh42d1WpkPlSFmlV mPRuubJBOa4M4vF19l1U3+6IU3ee+UOpbo5JyDQ9EMDrSDxvRmjpzsCekD2hspvQC7fwKg pdEsnXGZvSTphJrd1x52d/duHpuQ6iQ= 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 29D2C2C141; Mon, 13 Jun 2022 11:24:14 +0000 (UTC) Date: Mon, 13 Jun 2022 13:24:10 +0200 From: Petr Mladek To: Peter Geis Cc: John Ogness , Sergey Senozhatsky , Linux Kernel Mailing List , "open list:ARM/Rockchip SoC..." Subject: Re: [BUG] Threaded printk breaks early debugging Message-ID: References: <87y1y48spg.fsf@jogness.linutronix.de> <87zgihlbst.fsf@jogness.linutronix.de> 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 Sun 2022-06-12 19:30:27, Peter Geis wrote: > On Sun, Jun 12, 2022 at 7:08 PM John Ogness wrote: > > > > On 2022-06-10, Peter Geis wrote: > > > This might be a side effect of the fact that this is on a low powered > > > arm64 board. I noticed with threading enabled during large bursts the > > > console drops an excessive amount of messages. What do you mean that console drops an excessive amount of messages, please? Do you see "dropped XXX messages" in the console output? Or something else? > > > It's especially > > > apparent during the handover from earlycon to the normal console. > > > > I guess you have a very small kernel buffer and are generating unusually > > high amounts of messages? Is there a reason you cannot use a larger > > buffer? > > The buffer isn't an issue here, everything is available in dmesg when > userspace becomes available. Instead some messages bound for the > serial console are never output. This is strage. The message "dropped XXX messages" is printed only when the buffer was full and the oldest messages were overwritten before they were pushed to the console. If "dmesg" shows all messages it means that no messages were overwritten. Best Regards, Petr