Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751056AbVKUQvM (ORCPT ); Mon, 21 Nov 2005 11:51:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751059AbVKUQvM (ORCPT ); Mon, 21 Nov 2005 11:51:12 -0500 Received: from gold.veritas.com ([143.127.12.110]:51827 "EHLO gold.veritas.com") by vger.kernel.org with ESMTP id S1751054AbVKUQvL (ORCPT ); Mon, 21 Nov 2005 11:51:11 -0500 Date: Mon, 21 Nov 2005 16:51:14 +0000 (GMT) From: Hugh Dickins X-X-Sender: hugh@goblin.wat.veritas.com To: Russell King cc: Takashi Iwai , Lee Revell , Miles Lane , Andrew Morton , LKML , alsa-devel Subject: Re: 2.6.15-rc1-mm2 -- Bad page state at free_hot_cold_page (in process 'aplay', page c18eef30) In-Reply-To: <20051121155239.GC21032@flint.arm.linux.org.uk> Message-ID: References: <1132510467.6874.144.camel@mindpipe> <20051121155239.GC21032@flint.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-OriginalArrivalTime: 21 Nov 2005 16:51:11.0032 (UTC) FILETIME=[C6BA4B80:01C5EEBB] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1208 Lines: 27 On Mon, 21 Nov 2005, Russell King wrote: > > Does this mean that in arch/arm/mm/consistent.c, we should also set > __GFP_COMP ? Should we be doing that today? No, I don't believe so. I notice there's use of PageReserved and page count manipulation in there, which we may well want to rationalize in a later phase, perhaps replacing by __GFP_COMP then; but I don't see any need to change what you're doing at this stage. Looking again, to see why you even thought you might need to change: the vital thing you're doing (aside from the PageReserved, which is becoming irrelevant), which is missing from the regular high-order allocation, is the set_page_count(page, 1). That's why you don't need to change: the problems I was writing of come from when the 0-order page count goes down to 0. Makes me wonder whether there could be a useful halfway stage to compound pages, whether it would help for the page allocator to set those counts to 1 generally. Hugh - 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/