Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261168AbVEPUli (ORCPT ); Mon, 16 May 2005 16:41:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261852AbVEPUli (ORCPT ); Mon, 16 May 2005 16:41:38 -0400 Received: from serv01.siteground.net ([70.85.91.68]:459 "EHLO serv01.siteground.net") by vger.kernel.org with ESMTP id S261168AbVEPUl3 (ORCPT ); Mon, 16 May 2005 16:41:29 -0400 Date: Mon, 16 May 2005 12:43:17 -0700 (PDT) From: christoph X-X-Sender: christoph@ScMPusgw To: Dave Hansen cc: linux-mm , shai@scalex86.org, Linux Kernel Mailing List Subject: Re: [PATCH] Factor in buddy allocator alignment requirements in node memory alignment In-Reply-To: <1116274451.1005.106.camel@localhost> Message-ID: References: <1116274451.1005.106.camel@localhost> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - serv01.siteground.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [0 0] / [47 12] X-AntiAbuse: Sender Address Domain - scalex86.org X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1280 Lines: 34 On Mon, 16 May 2005, Dave Hansen wrote: > On Mon, 2005-05-16 at 12:05 -0700, christoph wrote: > > Memory for nodes on i386 is currently aligned on 2 MB boundaries. > > However, the buddy allocator needs pages to be aligned on > > PAGE_SIZE << MAX_ORDER which is 8MB if MAX_ORDER = 11. > > Why do you need this? Are you planning on allowing NUMA KVA remap pages > to be handed over to the buddy allocator? That would be a major > departure from what we do now, and I'd be very interested in seeing how > that is implemented before a infrastructure for it goes in. Because the buddy allocator is complaining about wrongly allocated zones! in page_alloc.c: static void __init free_area_init_core(struct pglist_data *pgdat, unsigned long *zones_size, unsigned long *zholes_size) { ... const unsigned long zone_required_alignment = 1UL << (MAX_ORDER-1); ... if ((zone_start_pfn) & (zone_required_alignment-1)) printk(KERN_CRIT "BUG: wrong zone alignment, it will crash\n"); - 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/