Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754109AbXLGLNO (ORCPT ); Fri, 7 Dec 2007 06:13:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751455AbXLGLM7 (ORCPT ); Fri, 7 Dec 2007 06:12:59 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:56925 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751127AbXLGLM6 (ORCPT ); Fri, 7 Dec 2007 06:12:58 -0500 Date: Fri, 7 Dec 2007 12:12:15 +0100 From: Ingo Molnar To: Andrew Morton Cc: Stefano Brivio , Robert Love , linux-kernel@vger.kernel.org, Dave Jones , "Rafael J. Wysocki" , Michael Buesch , Thomas Gleixner , Len Brown Subject: Re: [PATCH] scheduler: fix x86 regression in native_sched_clock Message-ID: <20071207111215.GA9502@elte.hu> References: <20071207021952.6f0ac922@morte> <20071207084559.GA11162@elte.hu> <20071207023241.15274ef6.akpm@linux-foundation.org> <20071207104013.GC27307@elte.hu> <20071207030954.8c1fedc5.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071207030954.8c1fedc5.akpm@linux-foundation.org> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 835 Lines: 23 * Andrew Morton wrote: > > > A bit risky - it's quite an expansion of code which no longer can > > > call printk. > > > > > > You might want to take that WARN_ON out of __update_rq_clock() ;) > > > > hm, dont we already detect printk recursions and turn them into a > > silent return instead of a hang/crash? > > We'll pop the locks and will proceed to do the nested printk. So > __update_rq_clock() will need rather a lot of stack ;) yeah. That behavior of printk is rather fragile. I think my previous patch should handle all such incidents. Ingo -- 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/