From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765979AbYBUNER (ORCPT ); Thu, 21 Feb 2008 08:04:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757225AbYBUND7 (ORCPT ); Thu, 21 Feb 2008 08:03:59 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:56601 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755564AbYBUND6 (ORCPT ); Thu, 21 Feb 2008 08:03:58 -0500 Date: Thu, 21 Feb 2008 14:03:32 +0100 From: Ingo Molnar To: Joerg Roedel Cc: tglx@linutronix.de, mingo@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] X86: remove WARN_ON if MTRRs are all blank Message-ID: <20080221130332.GA16152@elte.hu> References: <1203593558-3391-1-git-send-email-joerg.roedel@amd.com> <20080221115452.GB13948@elte.hu> <20080221124735.GA20053@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080221124735.GA20053@amd.com> 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 * Joerg Roedel wrote: > > > if (!highest_pfn) { > > > printk(KERN_WARNING "WARNING: strange, CPU MTRRs all blank?\n"); > > > - WARN_ON(1); > > > return 0; > > > } > > > > instead of obscuring a possibly useful warning, please instead > > detect that it's a KVM guest and skip both the warning and the > > backtrace in that case. > > How usefull is the backtrace in that place? I agree that the printk > warning may be usefull, but I don't see why the backtrace from the > WARN_ON is necessary. it allows us to collect such things on kerneloops.org for example. Ingo