Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261607AbVADKro (ORCPT ); Tue, 4 Jan 2005 05:47:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261731AbVADKrf (ORCPT ); Tue, 4 Jan 2005 05:47:35 -0500 Received: from mx1.redhat.com ([66.187.233.31]:63372 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S261607AbVADKrd (ORCPT ); Tue, 4 Jan 2005 05:47:33 -0500 From: David Howells In-Reply-To: <28707.1104722227@ocs3.ocs.com.au> References: <28707.1104722227@ocs3.ocs.com.au> To: Keith Owens Cc: "Randy.Dunlap" , Jim Nelson , Alan Cox , Coywolf Qi Hunt , Jesper Juhl , LKML Subject: Re: printk loglevel policy? X-Mailer: MH-E 7.82; nmh 1.0.4; GNU Emacs 21.3.50.3 Date: Tue, 04 Jan 2005 10:46:45 +0000 Message-ID: <2583.1104835605@redhat.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1031 Lines: 26 Keith Owens wrote: > >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. The oops writer breaks the locks. It's _really_ annoying when oopses happen simultaneously on separate CPUs - the oops reports end up interleaved char-by-char. My patch serialised oops writing. David - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/