From patchwork Mon Aug 20 09:35:36 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wen Congyang X-Patchwork-Id: 1347511 Return-Path: X-Original-To: patchwork-linux-acpi@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id C3F533FC33 for ; Mon, 20 Aug 2012 09:33:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756084Ab2HTJct (ORCPT ); Mon, 20 Aug 2012 05:32:49 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:31798 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1756063Ab2HTJbG (ORCPT ); Mon, 20 Aug 2012 05:31:06 -0400 X-IronPort-AV: E=Sophos;i="4.77,796,1336320000"; d="scan'208";a="5673008" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 20 Aug 2012 17:29:42 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id q7K9Ueti021551; Mon, 20 Aug 2012 17:30:43 +0800 Received: from ghost.fnst.cn.fujitsu.com ([10.167.225.226]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2012082017304282-378325 ; Mon, 20 Aug 2012 17:30:42 +0800 From: wency@cn.fujitsu.com To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-ia64@vger.kernel.org, cmetcalf@tilera.com Cc: rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, cl@linux.com, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com, Wen Congyang Subject: [RFC V7 PATCH 13/19] memory-hotplug: check page type in get_page_bootmem Date: Mon, 20 Aug 2012 17:35:36 +0800 Message-Id: <1345455342-27752-14-git-send-email-wency@cn.fujitsu.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1345455342-27752-1-git-send-email-wency@cn.fujitsu.com> References: <1345455342-27752-1-git-send-email-wency@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/08/20 17:30:42, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/08/20 17:30:50, Serialize complete at 2012/08/20 17:30:50 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: Yasuaki Ishimatsu There is a possibility that get_page_bootmem() is called to the same page many times. So when get_page_bootmem is called to the same page, the function only increments page->_count. CC: David Rientjes CC: Jiang Liu CC: Len Brown CC: Benjamin Herrenschmidt CC: Paul Mackerras CC: Christoph Lameter Cc: Minchan Kim CC: Andrew Morton CC: KOSAKI Motohiro CC: Wen Congyang Signed-off-by: Yasuaki Ishimatsu --- mm/memory_hotplug.c | 15 +++++++++++---- 1 files changed, 11 insertions(+), 4 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 5f9f8c7..d85af6d 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -95,10 +95,17 @@ static void release_memory_resource(struct resource *res) static void get_page_bootmem(unsigned long info, struct page *page, unsigned long type) { - page->lru.next = (struct list_head *) type; - SetPagePrivate(page); - set_page_private(page, info); - atomic_inc(&page->_count); + unsigned long page_type; + + page_type = (unsigned long) page->lru.next; + if (page_type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE || + page_type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE){ + page->lru.next = (struct list_head *) type; + SetPagePrivate(page); + set_page_private(page, info); + atomic_inc(&page->_count); + } else + atomic_inc(&page->_count); } /* reference to __meminit __free_pages_bootmem is valid