From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932655Ab2DMIwk (ORCPT ); Fri, 13 Apr 2012 04:52:40 -0400 Received: from smtp.mei.co.jp ([133.183.100.20]:51864 "EHLO smtp.mei.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757443Ab2DMIwi (ORCPT ); Fri, 13 Apr 2012 04:52:38 -0400 Date: Fri, 13 Apr 2012 17:53:42 +0900 From: Akira Takeuchi To: linux-mm@kvack.org Subject: [PATCH RESEND][BUG] sparsemem: Initialize all memmap entries within sections Cc: linux-kernel@vger.kernel.org Message-Id: <20120413175342.FCE9.38390934@jp.panasonic.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.56.05 [ja] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This commit fixes the problem for the kernel with CONFIG_SPARSEMEM=y and CONFIG_HAVE_ARCH_PFN_VALID=y. VM subsystem insists that memmap entries within the align to MAX_ORDER_NR_PAGES must exist and be initialized. However, in the kernel with CONFIG_SPARSEMEM=y and CONFIG_HAVE_ARCH_PFN_VALID=y, the kernel only initializes the entries corresponding to the memory regions specified by "mem=" options. This causes "kernel BUG at mm/page_alloc.c:777!" This BUG message comes from the following BUG_ON() line in move_freepages(). BUG_ON(page_zone(start_page) != page_zone(end_page)); Signed-off-by: Akira Takeuchi Signed-off-by: Kiyoshi Owada --- include/linux/mmzone.h | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index dff7115..1b7538c 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1088,13 +1088,15 @@ static inline struct mem_section *__pfn_to_section(unsigned long pfn) return __nr_to_section(pfn_to_section_nr(pfn)); } -#ifndef CONFIG_HAVE_ARCH_PFN_VALID -static inline int pfn_valid(unsigned long pfn) +static inline int sparsemem_pfn_valid(unsigned long pfn) { if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS) return 0; return valid_section(__nr_to_section(pfn_to_section_nr(pfn))); } + +#ifndef CONFIG_HAVE_ARCH_PFN_VALID +#define pfn_valid(pfn) sparsemem_pfn_valid(pfn) #endif static inline int pfn_present(unsigned long pfn) @@ -1119,7 +1121,7 @@ static inline int pfn_present(unsigned long pfn) #define pfn_to_nid(pfn) (0) #endif -#define early_pfn_valid(pfn) pfn_valid(pfn) +#define early_pfn_valid(pfn) sparsemem_pfn_valid(pfn) void sparse_init(void); #else #define sparse_init() do {} while (0) -- 1.7.4.1