Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753891AbaFIB3T (ORCPT ); Sun, 8 Jun 2014 21:29:19 -0400 Received: from mail-ig0-f181.google.com ([209.85.213.181]:62931 "EHLO mail-ig0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753487AbaFIB3M (ORCPT ); Sun, 8 Jun 2014 21:29:12 -0400 MIME-Version: 1.0 In-Reply-To: <20140608181436.17de69ac@redhat.com> References: <20140608181436.17de69ac@redhat.com> Date: Sun, 8 Jun 2014 18:29:11 -0700 X-Google-Sender-Auth: DCJuZXrGGDL0m9V-5K8bnBa0hEA Message-ID: Subject: Re: [PATCH] x86: numa: drop ZONE_ALIGN From: Yinghai Lu To: Luiz Capitulino Cc: Andrew Morton , Andi Kleen , Rik van Riel , Yasuaki Ishimatsu , Linux MM , Linux Kernel Mailing List , "stable@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jun 8, 2014 at 3:14 PM, Luiz Capitulino wrote: > In short, I believe this is just dead code for the upstream kernel but this > causes a bug for 2.6.32 based kernels. > > The setup_node_data() function is used to initialize NODE_DATA() for a node. > It gets a node id and a memory range. The start address for the memory range > is rounded up to ZONE_ALIGN and then it's used to initialize > NODE_DATA(nid)->node_start_pfn. > The 2.6.32 kernel did use the rounded up range start to register a node's > memory range with the bootmem interface by calling init_bootmem_node(). > A few steps later during bootmem initialization, the 2.6.32 kernel calls > free_bootmem_with_active_regions() to initialize the bootmem bitmap. This > function goes through all memory ranges read from the SRAT table and try > to mark them as usable for bootmem usage. However, before marking a range > as usable, mark_bootmem_node() asserts if the memory range start address > (as read from the SRAT table) is less than the value registered with > init_bootmem_node(). The assertion will trigger whenever the memory range > start address is rounded up, as it will always be greater than what is > reported in the SRAT table. This is true when the 2.6.32 kernel runs as a > HyperV guest on Windows Server 2012. Dropping ZONE_ALIGN solves the > problem there. What is e820 memmap and srat from HyperV guest? Can you post bootlog first 200 lines? Thanks Yinghai -- 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/