Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762401AbYA1VRt (ORCPT ); Mon, 28 Jan 2008 16:17:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753675AbYA1VR1 (ORCPT ); Mon, 28 Jan 2008 16:17:27 -0500 Received: from outbound-va3.frontbridge.com ([216.32.180.16]:63976 "EHLO outbound3-va3-R.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750707AbYA1VR0 (ORCPT ); Mon, 28 Jan 2008 16:17:26 -0500 X-BigFish: VP X-MS-Exchange-Organization-Antispam-Report: OrigIP: 160.33.66.75;Service: EHS Message-ID: <479E459D.5080407@am.sony.com> Date: Mon, 28 Jan 2008 13:14:05 -0800 From: Tim Bird User-Agent: Thunderbird 2.0.0.6 (X11/20070926) MIME-Version: 1.0 To: Andrew Morton CC: a.p.zijlstra@chello.nl, rostedt@goodmis.org, dwalker@mvista.com, linux-kernel@vger.kernel.org, mingo@elte.hu, torvalds@linux-foundation.org, hch@infradead.org, mathieu.desnoyers@polymtl.ca, ghaskins@novell.com, acme@ghostprotocols.net, tglx@linutronix.de, sam@ravnborg.org, fche@redhat.com, jan.kiszka@siemens.com, johnstul@us.ibm.com, arjan@infradead.org, srostedt@redhat.com Subject: Re: [PATCH] defer printks in irqs References: <20080123160236.969334052@goodmis.org> <20080123160441.236562634@goodmis.org> <1201107978.13596.16.camel@imap.mvista.com> <1201110185.13596.22.camel@imap.mvista.com> <47991454.50603@am.sony.com> <1201214935.6341.105.camel@lappy> <47991DD7.9070009@am.sony.com> <20080126220151.784893b1.akpm@linux-foundation.org> In-Reply-To: <20080126220151.784893b1.akpm@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 28 Jan 2008 21:16:01.0825 (UTC) FILETIME=[FC056110:01C861F2] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1776 Lines: 49 Andrew Morton wrote: >> On Thu, 24 Jan 2008 15:23:03 -0800 Tim Bird wrote: >> Peter Zijlstra wrote: >>> I suspect these features reduce the chance a crash messages makes it out >>> onto the console, but fail to spot any of the copious text mention this >>> critical issue. >> Anything not in interrupts would not be deferred. >> The following code is meant to avoid deferring in oops as well. >> I'm not sure if that covers all crash cases or not. >> If you know of other cases, and ways to detect them, please advise. >> > > Yes, using oops_in_progress seems an appropriate fix for that. > > I assume that another downside is that printk-from-interrupt will now get > jumbled up with an interrupted pritk-from-non-interrupt. No. The order of printk messages (whether printk'ed from interrupt context or not) should not be affected. This patch should only affect the timing of when the messages are output to console. Note that an oops will flush any buffered messages ahead of the oops messages themselves. Some messages, not in oops, that were printk'ed in interrupt context, may still be in the log buffer but not have made it to console if the machine hangs hard. Because of this (IMO slight) downgrade in debugging utility, I chose to make the changes configurable. > Please use checkpatch. Will do from now on! Thanks! -- Tim ============================= Tim Bird Architecture Group Chair, CE Linux Forum Senior Staff Engineer, Sony Corporation of America ============================= -- 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/