From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261285AbVACDR3 (ORCPT ); Sun, 2 Jan 2005 22:17:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261286AbVACDR3 (ORCPT ); Sun, 2 Jan 2005 22:17:29 -0500 Received: from mail.ocs.com.au ([202.147.117.210]:42181 "EHLO mail.ocs.com.au") by vger.kernel.org with ESMTP id S261285AbVACDR0 (ORCPT ); Sun, 2 Jan 2005 22:17:26 -0500 X-Mailer: exmh version 2.6.3_20040314 03/14/2004 with nmh-1.0.4 From: Keith Owens To: "Randy.Dunlap" Cc: Jim Nelson , Alan Cox , Coywolf Qi Hunt , Jesper Juhl , David Howells , LKML Subject: Re: printk loglevel policy? In-reply-to: Your message of "Sun, 02 Jan 2005 13:41:34 -0800." <41D86A8E.9090400@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 03 Jan 2005 14:17:07 +1100 Message-ID: <28707.1104722227@ocs3.ocs.com.au> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 02 Jan 2005 13:41:34 -0800, "Randy.Dunlap" wrote: >Jim Nelson wrote: >> Or does printk() do some tracking that I didn't see as to where in the >> kernel the strings are coming from? > >That kind of garbled output has been known to happen, but >the is supposed to prevent that (along with >zap_locks() in kernel/printk.c). Using multiple calls to printk to print a single line has always been subject to the possibility of interleaving on SMP. We just live with the risk. Printing a complete line in a single call to printk is protected by various locks. Print a line in multiple calls is not protected. If it bothers you that much, build up the line in a local buffer then call printk once.