Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755805Ab2F0LMt (ORCPT ); Wed, 27 Jun 2012 07:12:49 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:53351 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752345Ab2F0LMs (ORCPT ); Wed, 27 Jun 2012 07:12:48 -0400 MIME-Version: 1.0 In-Reply-To: <1340795162.10063.28.camel@twins> References: <20120627060939.GD14913@gmail.com> <1340795162.10063.28.camel@twins> From: Kay Sievers Date: Wed, 27 Jun 2012 13:12:27 +0200 Message-ID: Subject: Re: cosmetic printk() issue with lockdep warning in arch/x86/kernel/alternative.c To: Peter Zijlstra Cc: Ingo Molnar , Steven Rostedt , Andrew Morton , Linus Torvalds , Thomas Gleixner , linux-kernel@vger.kernel.org, Greg Kroah-Hartmann , Lennart Poettering Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1237 Lines: 30 On Wed, Jun 27, 2012 at 1:06 PM, Peter Zijlstra wrote: > On Wed, 2012-06-27 at 12:49 +0200, Kay Sievers wrote: >> All we want is a reliable printk > > We too, but we define reliable differently. I want printk() to dump data > ASAP so that it has better chance to get out of the system and onto my > console in case of a crash. I don't give a rats arse about interleaved > text, any text is better than no text. Sure, I fully understand that this is useful. > So if you go add separate buffers in there that will delay writing text, > you're actively destroying printk(). > > Any change that makes it harder to get text out is bad. The text is always flushed immediately for full lines, there is no change at all. Since yesterday, continuation lines (which are buffered) are flushed immediately to the console too. I don't think there will be a substantial difference anymore to the old behaviour, but we still get reliable records stored in the kmsg buffer. Kay -- 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/