From patchwork Fri Oct 5 02:25:34 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yasuaki Ishimatsu X-Patchwork-Id: 189389 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id C67092C0411 for ; Fri, 5 Oct 2012 12:26:28 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756504Ab2JEC0M (ORCPT ); Thu, 4 Oct 2012 22:26:12 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:60125 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756117Ab2JEC0J (ORCPT ); Thu, 4 Oct 2012 22:26:09 -0400 Received: from m2.gw.fujitsu.co.jp (unknown [10.0.50.72]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id C73E93EE0C1; Fri, 5 Oct 2012 11:26:08 +0900 (JST) Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id AEE1745DD74; Fri, 5 Oct 2012 11:26:08 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 7D88045DE4E; Fri, 5 Oct 2012 11:26:08 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 632481DB8041; Fri, 5 Oct 2012 11:26:08 +0900 (JST) Received: from g01jpexchkw02.g01.fujitsu.local (g01jpexchkw02.g01.fujitsu.local [10.0.194.41]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 139AE1DB8038; Fri, 5 Oct 2012 11:26:08 +0900 (JST) Received: from [127.0.0.1] (10.124.101.33) by g01jpexchkw02.g01.fujitsu.local (10.0.194.41) with Microsoft SMTP Server id 14.2.309.2; Fri, 5 Oct 2012 11:26:06 +0900 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.7.4 Message-ID: <506E451E.1050403@jp.fujitsu.com> Date: Fri, 5 Oct 2012 11:25:34 +0900 From: Yasuaki Ishimatsu User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:15.0) Gecko/20120907 Thunderbird/15.0.1 MIME-Version: 1.0 To: , , , , , , , , , CC: Yasuaki Ishimatsu , , , , , , , , Subject: [PATCH 1/10] memory-hotplug : check whether memory is offline or not when removing memory References: <506E43E0.70507@jp.fujitsu.com> In-Reply-To: <506E43E0.70507@jp.fujitsu.com> Sender: sparclinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: sparclinux@vger.kernel.org When calling remove_memory(), the memory should be offline. If the function is used to online memory, kernel panic may occur. So the patch checks whether memory is offline or not. CC: David Rientjes CC: Jiang Liu CC: Len Brown CC: Christoph Lameter Cc: Minchan Kim CC: Andrew Morton CC: KOSAKI Motohiro Signed-off-by: Wen Congyang Signed-off-by: Yasuaki Ishimatsu --- drivers/base/memory.c | 39 +++++++++++++++++++++++++++++++++++++++ include/linux/memory.h | 5 +++++ mm/memory_hotplug.c | 17 +++++++++++++++-- 3 files changed, 59 insertions(+), 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux-3.6/drivers/base/memory.c =================================================================== --- linux-3.6.orig/drivers/base/memory.c 2012-10-04 14:22:57.000000000 +0900 +++ linux-3.6/drivers/base/memory.c 2012-10-04 14:45:46.653585860 +0900 @@ -70,6 +70,45 @@ void unregister_memory_isolate_notifier( } EXPORT_SYMBOL(unregister_memory_isolate_notifier); +bool is_memblk_offline(unsigned long start, unsigned long size) +{ + struct memory_block *mem = NULL; + struct mem_section *section; + unsigned long start_pfn, end_pfn; + unsigned long pfn, section_nr; + + start_pfn = PFN_DOWN(start); + end_pfn = PFN_UP(start + size); + + for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { + section_nr = pfn_to_section_nr(pfn); + if (!present_section_nr(section_nr)) + continue; + + section = __nr_to_section(section_nr); + /* same memblock? */ + if (mem) + if ((section_nr >= mem->start_section_nr) && + (section_nr <= mem->end_section_nr)) + continue; + + mem = find_memory_block_hinted(section, mem); + if (!mem) + continue; + if (mem->state == MEM_OFFLINE) + continue; + + kobject_put(&mem->dev.kobj); + return false; + } + + if (mem) + kobject_put(&mem->dev.kobj); + + return true; +} +EXPORT_SYMBOL(is_memblk_offline); + /* * register_memory - Setup a sysfs device for a memory block */ Index: linux-3.6/include/linux/memory.h =================================================================== --- linux-3.6.orig/include/linux/memory.h 2012-10-02 18:00:22.000000000 +0900 +++ linux-3.6/include/linux/memory.h 2012-10-04 14:44:40.902581028 +0900 @@ -106,6 +106,10 @@ static inline int memory_isolate_notify( { return 0; } +static inline bool is_memblk_offline(unsigned long start, unsigned long size) +{ + return false; +} #else extern int register_memory_notifier(struct notifier_block *nb); extern void unregister_memory_notifier(struct notifier_block *nb); @@ -120,6 +124,7 @@ extern int memory_isolate_notify(unsigne extern struct memory_block *find_memory_block_hinted(struct mem_section *, struct memory_block *); extern struct memory_block *find_memory_block(struct mem_section *); +extern bool is_memblk_offline(unsigned long start, unsigned long size); #define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<