From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6BEDCC00140 for ; Wed, 10 Aug 2022 11:18:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231971AbiHJLSV (ORCPT ); Wed, 10 Aug 2022 07:18:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50080 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231991AbiHJLST (ORCPT ); Wed, 10 Aug 2022 07:18:19 -0400 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D71C73306 for ; Wed, 10 Aug 2022 04:18:19 -0700 (PDT) Received: from pps.filterd (m0246631.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 27A8hhA1005452; Wed, 10 Aug 2022 11:18:15 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=message-id : date : subject : to : references : from : in-reply-to : content-type : content-transfer-encoding : mime-version; s=corp-2022-7-12; bh=htr2h1MI2QWSSLUW5CFXXVAcV5OVx9/YznjtyNyRa7Q=; b=TIraLxjlJ8uFnszxPMNSJp0ak6RrFZJ5B6qbEsulkaDE8d5jgaLVchWOcrRENVwmP5EO JZ3cVF7lJtpVvLhKazABfuLQO9Ju3N28pyzwzQGIgATyePzJZ6lpOgnczlmkCh2c9sqY 9ZkCmyYjyzx2yCFmVXsTAjaZuVN+putULnBONI6PzZ4AEgptJ3bTUYoDFj8j2eZpE5K2 sSU1zmNGtePk0z5XlhAqtM438ofklxiM8xjHyTXWmtlCRNYVztgBtgunqzUO6DrRO03k ggQnIXeQoqkmOTSCzeI4Rp9pL7xYZPXBlBWp7oDFy7JFRbvTZnX59XCBUjMHodB46D11 8A== Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.appoci.oracle.com [138.1.114.2]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3huwq91ks9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 10 Aug 2022 11:18:15 +0000 Received: from pps.filterd (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.5/8.17.1.5) with ESMTP id 27A9KrQL015358; Wed, 10 Aug 2022 11:18:14 GMT Received: from nam10-mw2-obe.outbound.protection.outlook.com (mail-mw2nam10lp2103.outbound.protection.outlook.com [104.47.55.103]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 3huwqj1s2k-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 10 Aug 2022 11:18:14 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=lBRWZnKePmiQJRURsJz1ogbo62+KLXvVmOJzk0GvR3HUhJAaTdWRVQ4PoaBs/0yl1ntpMcbCkZpi3V/MJj7036vvQIcp9tRKhKW4JM8TKlnFHOEcVKp53nGCd0uNtYCGTmbgOUJiKPPHk7OnQpfvFrhPAtuMkQkm5EwAEIRuTuSBU3xXegzmtqVtSSNa+7bTR/ORDSDg3kw94hwqQ+/nRWFNDgxMZcFg5qPvEhMvi4B2qFwxIXYz/prvwyXlQlxWXFiVmDpfvIAqkoiOa+WynHTRjc66gqRT1uWKknoHHtqSrwPbD2PRKtcAHOD54rtqrbcCaoQbbKAhwzQqULiWRA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=htr2h1MI2QWSSLUW5CFXXVAcV5OVx9/YznjtyNyRa7Q=; b=NtfpkxQZ5+Y2zNLKDm3xERUQeoR4x2SoQVojgxwOj4NZuW0agiIHDU2+todj6zT7Lm625X/j/oq0+LtFTY2o4rXkSDoorcQesNrIPnGGtyHx/zzT4JUf52B1ydVY+7sXUtUTZUoDd95JD3zSJBmAa8GxSUHJUWiWaY4RaUo4oZTdsT4sB81Qp8TJVOKHOyfrp0+mqaq6d+6+ZuSKQS3zfoUIwAlVY1LMBvi7dUBvMRmsN6hnUXEbFY7s2NM2BbDjWRP/pcy/69UnzKOrVU4SirwwcTja7LU9RFD9AHnOszfl2KhElP0jE3xPRh2058WaUEFyPpkD96ewqWRiYmdnVQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=htr2h1MI2QWSSLUW5CFXXVAcV5OVx9/YznjtyNyRa7Q=; b=fa8ivxfM46w6U/O0Zq5ce9hUzwVOziN3EslE4Bxx+Z13AVspZ8xKFoI5tfFIX7FQ6BtqRTdlG5BouLcFealAno6Hh8AAMBCuX51LDJMnd5Km6nhJsocVvHWhr/Y5Bbc0yPoiSGh+OpyyvqoAPcwPDoUgQ9otqjuAHCHzntJKOyQ= Received: from PH0PR10MB5706.namprd10.prod.outlook.com (2603:10b6:510:148::10) by CY4PR1001MB2135.namprd10.prod.outlook.com (2603:10b6:910:41::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5458.24; Wed, 10 Aug 2022 11:18:12 +0000 Received: from PH0PR10MB5706.namprd10.prod.outlook.com ([fe80::55d1:d16a:c681:2078]) by PH0PR10MB5706.namprd10.prod.outlook.com ([fe80::55d1:d16a:c681:2078%8]) with mapi id 15.20.5504.021; Wed, 10 Aug 2022 11:18:11 +0000 Message-ID: Date: Wed, 10 Aug 2022 19:18:07 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.12.0 Subject: Re: [PATCH 0/2] btrfs-progs: read device fsid from the sysfs To: Qu Wenruo , linux-btrfs@vger.kernel.org References: From: Anand Jain In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: SI2PR02CA0016.apcprd02.prod.outlook.com (2603:1096:4:194::9) To PH0PR10MB5706.namprd10.prod.outlook.com (2603:10b6:510:148::10) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 7a1c5aca-6416-4d33-8c4d-08da7ac202db X-MS-TrafficTypeDiagnostic: CY4PR1001MB2135:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH0PR10MB5706.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230016)(366004)(376002)(346002)(136003)(39860400002)(396003)(53546011)(31686004)(44832011)(66476007)(2616005)(38100700002)(6506007)(36756003)(186003)(8936002)(83380400001)(41300700001)(86362001)(6512007)(2906002)(66946007)(6666004)(26005)(5660300002)(478600001)(66556008)(316002)(31696002)(8676002)(6486002)(43740500002)(45980500001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?OTlnWklLdW5mOXRYdWE5V3paaGZlcGx2ZkVUNlNoalRVeVpvV0FMNkVEaFl1?= =?utf-8?B?bnIxQ0NwY3FqcjVDWVdNWXlEQVFpUEJVY0VxSlBNM2dhR1pVcnlkMVRVSk1Q?= =?utf-8?B?cU0reUhNbk9Na1RFOW5tbEoyUklOaTVtZG4wQjdJMnh5WEtDZlZvemFIQXNR?= =?utf-8?B?OU5qL0ZIQURNd3diazhWR21jSUV2alU0TzUyQ0VNWk9HUmk4VmdBOHhkK1R5?= =?utf-8?B?cVBHUVpTQlJCOVFMM0dENXdSSmJkSC9KaW1UY2JqOXh6Nk52SjRmanp2MWVk?= =?utf-8?B?aHFCUXNrTEJxZUNnWTlOQi9LZTJSM0VMZTIzRFY0UDB4VVNRZ3VBYm1SWmJ6?= =?utf-8?B?MW9qL1RPdndjOWwvNUVOOXFkMFpJd3RBSDBJRlViMlF0TkdlUkJvMTFFUTZr?= =?utf-8?B?R1Brd2J6Vk9vUU1XVWE1REJkMGpDTElnVjVMMmpzeXVEQSt5c2wvQUtzQitW?= =?utf-8?B?cUF3S3lSRlVoSHViMlUrQnpMZSsvWExNU1BGQUljeG1MelBVZnE1NWJSZTUr?= =?utf-8?B?RDhQN05nTEEvZlFIeHh5dUJDVmN1YXBqRit4NDFpOEFsc3V1VkRvQ09MRmNZ?= =?utf-8?B?V05GS05PeCtjYTdNZ2tFN3lxZXJKajZyRkx1K0s3VVIwbWNqWk01Ui9DdFRC?= =?utf-8?B?U1lEcllmZHI2SnMzeW52QnlJTEZkckg0RTh6TGI2RjhPWktGbkVTYzI2WThD?= =?utf-8?B?TUlnaGRHYjkrNlNhU0h2MEhZTTFudEtOaUtCNStOdUloOUxDOGNBSDZnbVpt?= =?utf-8?B?TkFSZkdXTUliYUZDc2tFc2w4a2Z4NnAxTkhHaFFHUFQwWi9Oa2MwQlhuSDVJ?= =?utf-8?B?Rm4yYzhvYU9lbytmUEhtZ0tqZWtQalBaWEp0T1VrTTIrTVVFZ1kxbzY3Z0dp?= =?utf-8?B?UVU1b054QjdJN3lsWi9TcmRaSGMrVVVLUWYrbG56RjVKSmdBYnNqd041dUIr?= =?utf-8?B?L2NkRmN3QXNDUUhzN2oyTis4ZnRoUDArSmxxZHdaY20rcHhhRlBnd29UL3ZW?= =?utf-8?B?bEZrVldRVzRWME9QSmQveUl6bGgwTkJBVDUzVzBrS1lLVUQ5YVBrU1RGZHRs?= =?utf-8?B?alpQejNlclNBaTVVbUZRajFseENKakY3TWg0b3ExRGNiMmtHQXBZOHNzNUYw?= =?utf-8?B?cW9OcUQ0eklVM2NITVFaNlZLQlZidmNzR2I2NWJ4UWVvZjE2SlZWS0pTS2FJ?= =?utf-8?B?M3BYWEl4c1ZqYnFUWVlBK1o1M1I5aTZvMXpHbmZyaUswSjMxaWQ1UjRmWUdF?= =?utf-8?B?VzFIT0hFQnVkdHBmcVhCYk95Vm00UjcycUMvRWJNZnZoNjRhQmRZa0ZhbmFp?= =?utf-8?B?ZWdGUVJpYk9vYzFZQmpJOVpGSW9mYUg3MGNuWkswbzJqMzJxYVY4MGhHUGNX?= =?utf-8?B?K3pFeExCTFJodk5LWjFYZllBU0s4d2pkRElYa04yL1I4SUtmRld4aEZqaUFa?= =?utf-8?B?bVF0QUpRalQwS1YrTGVYcFVZWVFVazYwa0kyN25KOTJ4djZBenZ0ekpsNXRP?= =?utf-8?B?ZXkyRm16SHZBSy8rWngzVVFhZG5ZUmdQNWdqSHFlMW9pVzM4U1hLZlVPK29J?= =?utf-8?B?ckFZaE1PZXNoT0F5d1I4V3YxSFB2NkpWSGh2M2hrQUs2eGhJV2tXK09yUUN6?= =?utf-8?B?U2tDcU8yQ2doRFltV0E5eU04cHNhKzlQbDFwQjFNOSt4N0p3VmwrNHJwQlh2?= =?utf-8?B?aUw3Q0lraEpoc3VmSHF1VEl6eXhSZFYrNXlKUEFQaUVacFBWdlROcGN5eUR6?= =?utf-8?B?T3MzdGE4SDBCL0ZBK2g1N2dSb2NYSmdGSmk1U1BkRnlUeHg3dnh4YjNQQld6?= =?utf-8?B?OTdjZlU3UTdxclorRmhWaEMxZk5Eb1Z1WFdSRGhyRzhhT1MwSkFzUnQyaXF6?= =?utf-8?B?eXQ0OHd2WE4vQmN4dHM1aTVkNXhPT1RZRkNpN2hYUnBRSCtPWmhFRkU1eHNH?= =?utf-8?B?RGdBbzFPYTR2YkdSMUpkcEMzcnBGS3BiaU9kQmt3RE9Pa0hldi9zMWtzenJn?= =?utf-8?B?WFduTUtWODhpUXNKcU5GNjRhMDAyMVZXYTFzNnN3REw4dzkyMndpQ1lRK2Ew?= =?utf-8?B?VytlTjRZOWkyZUN0TGlCeFJFTWhpTUhpdHdBelFUZit2dzFCbzk4aXVEbHpy?= =?utf-8?Q?QghlnIPMfEVIh3z2YV2P1yVc3?= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7a1c5aca-6416-4d33-8c4d-08da7ac202db X-MS-Exchange-CrossTenant-AuthSource: PH0PR10MB5706.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Aug 2022 11:18:11.9345 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: jdy3CHerkNUWVPKGRqT16n0L7xjhYiW9uGmoULDeZTWkns87D29Ef8PRMlEkBe2etxs9G/G4DBQRYpbGl21qYA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR1001MB2135 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-08-10_06,2022-08-10_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 suspectscore=0 spamscore=0 phishscore=0 adultscore=0 mlxscore=0 malwarescore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2208100034 X-Proofpoint-GUID: 7az5mJFidNJUR6CHv454REJ25iZN1LLn X-Proofpoint-ORIG-GUID: 7az5mJFidNJUR6CHv454REJ25iZN1LLn Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 10/08/2022 18:18, Qu Wenruo wrote: > > > On 2021/10/19 08:23, Anand Jain wrote: >> The following test case fails as it trying to read the fsid from the sb >> for a missing device. >> >>     $ mkfs.btrfs -f -draid1 -mraid1 $DEV1 $DEV2 >>     $ btrfstune -S 1 $DEV1 > > I just wonder, should we even allow seed device setting for multi-device > btrfs? Hmm. A desktop use-case which gets reset back to the golden image at EOD or a user logout may use fault tolerance to reduce unplanned downtime. I say we keep this feature. Further, if we allow a seed device to replace by another seed device it will help also. > This doesn't sound correct to me, and can lead to split-brain problems. Split-brain can happen even without seed devices. There is a patch for split-brain detection and avoiding. I love to revive it if there are enough interests. Thanks, Anand > Thanks, > Qu >>     $ wipefs -a $DEV2 >>     $ btrfs dev scan --forget >>     $ mount -o degraded $DEV1 /btrfs >>     $ btrfs device add $DEV3 /btrfs -f >> >>     $ btrfs fi us /btrfs >>       ERROR: unexpected number of devices: 1 >= 1 >>       ERROR: if seed device is used, try running this command as root >> >> The kernel patch [1] in the mailing list provided a sysfs interface >> to read the fsid of the device, so use it instead. >> >>   [1]  btrfs: sysfs add devinfo/fsid to retrieve fsid from the device >> >> This patch also retains the old method that is to read the SB for >> backward compatibility purposes. >> >> Anand Jain (2): >>    btrfs-progs: prepare helper device_is_seed >>    btrfs-progs: read fsid from the sysfs in device_is_seed >> >>   cmds/filesystem-usage.c | 47 ++++++++++++++++++++++++++++++++++++----- >>   1 file changed, 42 insertions(+), 5 deletions(-) >>