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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 69269C43382 for ; Thu, 27 Sep 2018 10:02:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1D9D721571 for ; Thu, 27 Sep 2018 10:02:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D9D721571 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727357AbeI0QTr (ORCPT ); Thu, 27 Sep 2018 12:19:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:60156 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727015AbeI0QTq (ORCPT ); Thu, 27 Sep 2018 12:19:46 -0400 Received: from vmware.local.home (cpe-66-24-56-78.stny.res.rr.com [66.24.56.78]) (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 60D0321571; Thu, 27 Sep 2018 10:02:16 +0000 (UTC) Date: Thu, 27 Sep 2018 06:02:04 -0400 From: Steven Rostedt To: Petr Mladek Cc: Sergey Senozhatsky , Sergey Senozhatsky , linux-kernel@vger.kernel.org Subject: Re: [PATCH] printk: CON_PRINTBUFFER console registration is a bit racy Message-ID: <20180927060107.2ef35dfb@vmware.local.home> In-Reply-To: <20180926113715.6llme2vmvynzuoa3@pathway.suse.cz> References: <20180914023428.814-1-sergey.senozhatsky@gmail.com> <20180914085934.m2bgixltdzpfh62o@pathway.suse.cz> <20180914111953.GA20572@tigerII.localdomain> <20180926113715.6llme2vmvynzuoa3@pathway.suse.cz> X-Mailer: Claws Mail 3.15.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 26 Sep 2018 13:37:15 +0200 Petr Mladek wrote: > If you really want this change, please add a comment, for example: > > /* > * Set exclusive_console still with disabled interrupts to > * reduce race window with eventual console_flush_on_panic() > * that ignores console_lock. > */ > > I am not against the change. It makes some sense and it does > not break anything. It is just not obvious and might either > get easily lost again or it might cause confusion. I mean that > it might cause false feeling that exclusive_console is > synchronized by logbuf_lock. > > printk code already is complex enough without this subtle > tricks. I'm fine with the change and agree that a comment should be added. -- Steve