From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764853AbYDPOC4 (ORCPT ); Wed, 16 Apr 2008 10:02:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754024AbYDPOCs (ORCPT ); Wed, 16 Apr 2008 10:02:48 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:56883 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752951AbYDPOCs (ORCPT ); Wed, 16 Apr 2008 10:02:48 -0400 Date: Wed, 16 Apr 2008 16:02:33 +0200 From: Ingo Molnar To: Mel Gorman Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/4] Make defencive checks around PFN values registered for memory usage Message-ID: <20080416140233.GC24383@elte.hu> References: <20080416135058.1346.65546.sendpatchset@skynet.skynet.ie> <20080416135218.1346.41125.sendpatchset@skynet.skynet.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080416135218.1346.41125.sendpatchset@skynet.skynet.ie> 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 * Mel Gorman wrote: > + if (*start_pfn > max_sparsemem_pfn) { > + mminit_debug_printk(MMINIT_VERIFY, "pfnvalidation", > + "Start of range %lu -> %lu exceeds SPARSEMEM max %lu\n", > + *start_pfn, *end_pfn, max_sparsemem_pfn); small request: please emit a WARN_ON_ONCE() as well, so that kerneloops.org (and automated test setups) picks it up. > + mminit_debug_printk(MMINIT_VERIFY, "pfnvalidation", > + "End of range %lu -> %lu exceeds SPARSEMEM max %lu\n", > + *start_pfn, *end_pfn, max_sparsemem_pfn); ditto - all errors should be fixed up and we should try to continue as far as possible, but emitting a WARN_ON_ONCE() will be very useful in making sure people notice the warning. Ingo