Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751974AbbG3X5Q (ORCPT ); Thu, 30 Jul 2015 19:57:16 -0400 Received: from mail-bn1on0117.outbound.protection.outlook.com ([157.56.110.117]:20836 "EHLO na01-bn1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751063AbbG3X5P convert rfc822-to-8bit (ORCPT ); Thu, 30 Jul 2015 19:57:15 -0400 From: "Alex Ng (LIS)" To: Nathan Zimmer CC: Mel Gorman , Robin Holt , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 03/13] mm: meminit: Only set page reserved in the memblock region Thread-Topic: Re: [PATCH 03/13] mm: meminit: Only set page reserved in the memblock region Thread-Index: AdDLHA2j5N/yLhkpTTeIK9YXYPgdFg== Date: Thu, 30 Jul 2015 23:41:49 +0000 Message-ID: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: sgi.com; dkim=none (message not signed) header.d=none; x-originating-ip: [2001:4898:80e8::25a] x-microsoft-exchange-diagnostics: 1;BY2PR0301MB1656;24:KRHLXSh2QH7O62H9jVE26dfLsm/p6B71mayldpyPMyEUi3aRtMdiCU3SBJ2cdQlFjr1PYPh5P3Tid10FMlD78kLGxj74iP5ZT5NT27IGI3g=;20:x+Lh54RR62R2q7pPDl0AdN73sFAxip62WwcUJhETyH5COiqVNhU9yJrmlISwciA/RTwwGZyvoqa9mU7jDvb0+A== x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:BY2PR0301MB1656; by2pr0301mb1656: X-MS-Exchange-Organization-RulesExecuted x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:; x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(601004)(2401001)(5005006)(3002001);SRVR:BY2PR0301MB1656;BCL:0;PCL:0;RULEID:;SRVR:BY2PR0301MB1656; x-forefront-prvs: 06530126A4 x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(6009001)(102836002)(92566002)(189998001)(5001960100002)(86362001)(77156002)(575784001)(122556002)(5003600100002)(40100003)(2900100001)(110136002)(62966003)(99286002)(5002640100001)(54356999)(77096005)(5001920100001)(50986999)(74316001)(33656002)(2656002)(10090500001)(87936001)(76576001)(46102003)(3826002);DIR:OUT;SFP:1102;SCL:1;SRVR:BY2PR0301MB1656;H:BY2PR0301MB1655.namprd03.prod.outlook.com;FPR:;SPF:None;MLV:sfv;LANG:en; Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-originalarrivaltime: 30 Jul 2015 23:41:49.7929 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY2PR0301MB1656 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1031 Lines: 20 Hi, While testing builds containing this change (commit id: 92923ca3aacef63c92dc297a75ad0c6dfe4eab37), I've observed that memory fails to come online in the hotplug case. When attempting to bring the hot added pages online (via udev rules or manually writing to sysfs); it's failing with -EBUSY error because the hot added pages no longer have the Reserved flag set. The reserved bit is being checked in memory_block_action() in drivers/base/memory.c: switch (action) { case MEM_ONLINE: if (!pages_correctly_reserved(start_pfn)) return -EBUSY; Should the reserved bit be set in some other place? Or should the above test be removed from sysfs memory device? -- Alex Ng -- 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/