Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932447AbVJLR3p (ORCPT ); Wed, 12 Oct 2005 13:29:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932444AbVJLR3p (ORCPT ); Wed, 12 Oct 2005 13:29:45 -0400 Received: from e32.co.us.ibm.com ([32.97.110.150]:44931 "EHLO e32.co.us.ibm.com") by vger.kernel.org with ESMTP id S932447AbVJLR3o (ORCPT ); Wed, 12 Oct 2005 13:29:44 -0400 Message-ID: <434D47FF.1000602@austin.ibm.com> Date: Wed, 12 Oct 2005 12:29:35 -0500 From: Joel Schopp User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.10) Gecko/20050909 Fedora/1.7.10-1.3.2 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Mel Gorman CC: mike kravetz , akpm@osdl.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lhms-devel@lists.sourceforge.net Subject: Re: [Lhms-devel] Re: [PATCH 5/8] Fragmentation Avoidance V17: 005_fallback References: <20051011151221.16178.67130.sendpatchset@skynet.csn.ul.ie> <20051011151246.16178.40148.sendpatchset@skynet.csn.ul.ie> <20051012164353.GA9425@w-mikek2.ibm.com> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 996 Lines: 19 > In reality, no and it would only happen if a caller had specified both > __GFP_USER and __GFP_KERNRCLM in the call to alloc_pages() or friends. It > makes *no* sense for someone to do this, but if they did, an oops would be > thrown during an interrupt. The alternative is to get rid of this last > element and put a BUG_ON() check before the spinlock is taken. > > This way, a stupid caller will damage the fragmentation strategy (which is > bad). The alternative, the kernel will call BUG() (which is bad). The > question is, which is worse? > If in the future we hypothetically have code that damages the fragmentation strategy we want to find it sooner rather than never. I'd rather some kernels BUG() than we have bugs which go unnoticed. - 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/