From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.openvz.org (mail.openvz.org [69.168.225.77]) by lore.virtuozzo.com (Postfix) with ESMTPS id 3FDCD8017D for ; Thu, 29 Oct 2026 15:46:18 +0000 (UTC) Received: from mail.openvz.org (localhost [127.0.0.1]) by mail.openvz.org (8.14.4/8.14.4) with ESMTP id 69TFipq5001943; Thu, 29 Oct 2026 18:44:52 +0300 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.openvz.org 69TFipq5001943 Authentication-Results: mail.openvz.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=virtuozzo.com header.i=@virtuozzo.com header.b="WbSCnjFZ" Received: from mail-pf1-f198.google.com (mail-pf1-f198.google.com [209.85.210.198]) by mail.openvz.org (8.14.4/8.14.4) with ESMTP id 69TFinYi001939 (version=TLSv1/SSLv3 cipher=AES128-GCM-SHA256 bits=128 verify=FAIL) for ; Thu, 29 Oct 2026 18:44:50 +0300 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.openvz.org 69TFinYi001939 Received: by mail-pf1-f198.google.com with SMTP id d2e1a72fcca58-89e6ddd4554so1648458b3a.3 for ; Thu, 29 Oct 2026 08:44:50 -0700 (PDT) X-Gm-Message-State: AFq9FYKDySbh9QlYOqLrsTJOmCNDGFn1Fuzeq4FV0p9HogqSyvKota8D rBRxBWxBadHPR6EgFlvrg70LvZuoBMiCFKJB8RAy4vQgm3YAQk8BFXlbw+qPArOn8YJN+57fAYQ UtMQ7q/RC0pQShTEXHiFds8axUaRjbmE9tz0X2WYQ5CqtOjdGF15t2g== X-Gm-Gg: AYBFou1oBvgnoSxxL3DurjDQrqpVlForV+9qxN5/wPKPxhJLDwk2c3MzQeFb52/92DJ GrhOHrRGqKKdMR0Bl8iFTho++3CnS0GRNHGvk9s4ql1T1Nzh9zsioPSGoUJo2SBMSMkSbKP8ClQ H9UZ7WQ2jykBqtxlJ0d0YzvxpsUggsomfBC1aGIAcmI43TlyzIHsNTamocxfZCHcfWe5EmCFb5H IQBJYmFaPe1+mr0EQVFBRwFqIul6J85SrO91YxP2119dlzavWBtRWiZkXUgaL5Rkyu3YX9F/6wR YsjeCAzGhzbJ4MXRp0fGxJCMYA0SR02ePTYjWR1WMqY1aPHCj34oMrvO0B4aSr1ndzAGH5d8Zmh FHbNPzLUMCd52LzG2aJTTHh06dR1ObmUOWdM60hRA97vphnsw3dtTi070KTWFBgcnT5GK8OSVQi h/DFgbiek3pciNokk+pIxMl1QV X-Received: by 2002:a05:6a00:2ea0:b0:89f:d9b2:4a1c with SMTP id d2e1a72fcca58-8a6e78cfe0emr5038667b3a.28.1793288688817; Thu, 29 Oct 2026 08:44:48 -0700 (PDT) X-Received: by 2002:a05:6a00:2ea0:b0:89f:d9b2:4a1c with SMTP id d2e1a72fcca58-8a6e78cfe0emr5038641b3a.28.1793288688128; Thu, 29 Oct 2026 08:44:48 -0700 (PDT) ARC-Seal: i=2; a=rsa-sha256; t=1793288688; cv=pass; d=google.com; s=arc-20260327; b=iBDg1mboYdfW9HV2LD7KGoSzK5cP2eblpGsRzrv1Ag0/PV2aDnxlr0+bahC4xSOMIA DLTErDVvN2jTn5or0oB8Xn5ZsMsdYtPM0kF6tw825lPxMXsDwY6x+DtOFA0CRKszPZwW z6leNAtV30MbF1pcFDEUAy0zr698nE0LIyXLtiDxVmV6pI1tYyDnjcRx2cC/sMXuTlJ5 KnZbQ8c2vJa7rvBYhvWZ7bOdz4W2RpgWHr/T1qqfzi1OPY0UhZqi7od47ywRymEFCGlI uLXS5DW6MyZxd/BNENe4fXKldIu4249FiFpUd87/OrJ6WzzuwyehcoeMdtMg1XODZTwQ cXUQ== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20260327; h=mime-version:content-transfer-encoding:in-reply-to:from :content-language:references:cc:to:subject:user-agent:date :message-id:dkim-signature; bh=Xnhxu2co19x+rIQjYVpu1frq+ZstKY7pUXCzdEDoc2I=; fh=IBoZ6KBhIGQ2g4B1pmYJLuR4yLjH75t3qDKAR6Nb78c=; b=e2kNhlLKyNZAbv9zndIBKTqh7qaB/NAV0b70guTvoKL0UBgUfGB3g3a7uAHGh54n5k BKHC7prdAw9WOZbsdU6pfNywJ7t6aOlnEoRob9mRG8QQawDfc0CIwIgVL/Q+ilM0lm0u agIBeJPlzjmCgN/xIAKTwTYg7Z/hBvQ+pJ3zJUTWjlYE4uTXmTjgaMg+x2WTL+DKY6Wg LKYr5upSAMHSu4zF0yM2QwRm3/IuosBV0iz68n9Dd+/HSI6C5i0h14pkPm/jkJkBPCpv 6yCgmFwiQjqn+5HnKdmVwTzM14dh+xcacEoJrQb6Ipn3khsfzTtPyb/OxKcVT5kKmKUq Pv4A==; dara=google.com ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@virtuozzo.com header.s=selector2 header.b=WbSCnjFZ; arc=pass (i=1 spf=pass spfdomain=virtuozzo.com dkim=pass dkdomain=virtuozzo.com dmarc=pass fromdomain=virtuozzo.com); spf=pass (google.com: domain of khorenko@virtuozzo.com designates 2a01:111:f403:c202::7 as permitted sender) smtp.mailfrom=khorenko@virtuozzo.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=virtuozzo.com Received: from GVXPR05CU001.outbound.protection.outlook.com (mail-swedencentralazlp170130007.outbound.protection.outlook.com. [2a01:111:f403:c202::7]) by mx.google.com with ESMTPS id d2e1a72fcca58-8a98ffa2772si23608b3a.101.2026.10.29.08.44.47 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 29 Oct 2026 08:44:47 -0700 (PDT) Received-SPF: pass (google.com: domain of khorenko@virtuozzo.com designates 2a01:111:f403:c202::7 as permitted sender) client-ip=2a01:111:f403:c202::7; Authentication-Results: mx.google.com; dkim=pass header.i=@virtuozzo.com header.s=selector2 header.b=WbSCnjFZ; arc=pass (i=1 spf=pass spfdomain=virtuozzo.com dkim=pass dkdomain=virtuozzo.com dmarc=pass fromdomain=virtuozzo.com); spf=pass (google.com: domain of khorenko@virtuozzo.com designates 2a01:111:f403:c202::7 as permitted sender) smtp.mailfrom=khorenko@virtuozzo.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=virtuozzo.com ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=DVStPX/zPs6GgP4oLwlM1nP7TUmSvLYjULibbxFG8TrLw7c7tjAdQBbmqn8syIt6LYaSgb+/zBaFB3R6/XZ3T7Gk4RAudSGOKW9SShQY0QxMofqcxPC1j0n9WLj75WjDip+rMvOmDPHV5Of2UUCBcmkDlE4rMDVulvkHhL3zVUNgtqpkk0YCTDs1etkBweIqYoOdTWpQqoSrltqscujleSgiYvMi+aIpZfocW5x6xoEcepHnOUp23BeWQG8GlAwR/KhkD6F+wegdS1eYVhFpVpFTjcIgLa4eAmqU3n3bSZ6wdl02GeV4mUmuZTqTtzXneaiE7mVon+zGw5VwUkpSlg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=Xnhxu2co19x+rIQjYVpu1frq+ZstKY7pUXCzdEDoc2I=; b=L+Jkd5vw1UEN0yeCUASC1SUih5loLz8BXFZ8pj46p8+eb2Qn5/glmSmuIWlvQyU9u6bGwK4RwNHPOtfNQwtJOrtTalGuIgvaqJLC1ICLYR+oyNmAOZJ9mPfM2KtX7meUVKpsPuTvpetHZ/vQhxuWfeTILnLdXHyowAEptw3sImYDZ6k+LO9XST9A4A0eha0ba8zYxWu5/hAL4pNQ1CCyL6WgVJl0mfFXqhCMil22Uft3nblutCuycmEw3n275ddW3ioJL8ZqezNAcd9js9tHMzey5EaUzizzxrqp6GLOblFZKd6lIhZGNmIyrK1uNkqPbnMFFYFNuNvXGblbNB0LEw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=virtuozzo.com; dmarc=pass action=none header.from=virtuozzo.com; dkim=pass header.d=virtuozzo.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=virtuozzo.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Xnhxu2co19x+rIQjYVpu1frq+ZstKY7pUXCzdEDoc2I=; b=WbSCnjFZcRxnqcIchG8Ox3V3lWzLmBMAhqAYINxom7wHkl/QSBCucxHGKht/p5CquPhSsJliXUcywrKKB7NFgoG5iPlo+VHCJxzhPDuhcHo0HHlQhLLpZMbAX3Tj3e8KG2HIthFTcazL+6xe3R8qO5OTv/Mq2afMwBhfn2O0PvTuriASLv+ZmLnkLHRx8Rs6vejVWseFlMxZg4puD7gMbDYsgdw7mxLTqI+WjMnRViMEEOhxiRPwWiO8zB9Htw3xPzA7GbHDx35fcCRD8o2r7+2kIbmrYFI25k9udpZj6P9yxFU8Chr9zquSVbJ3xkygxmdN+3iW9jPfFw/e1um2mA== Authentication-Results: mx.microsoft.com 1; dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=virtuozzo.com; Received: from AS2PR08MB9075.eurprd08.prod.outlook.com (2603:10a6:20b:5ff::9) by AS8PR08MB6358.eurprd08.prod.outlook.com (2603:10a6:20b:337::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.569.8; Thu, 29 Oct 2026 15:44:45 +0000 Received: from AS2PR08MB9075.eurprd08.prod.outlook.com ([fe80::3f57:9ced:7a37:1bd8]) by AS2PR08MB9075.eurprd08.prod.outlook.com ([fe80::3f57:9ced:7a37:1bd8%4]) with mapi id 15.21.0569.007; Thu, 29 Oct 2026 15:44:44 +0000 Message-ID: <7b4d8be2-5992-4393-a049-29f1f6c34d91@virtuozzo.com> Date: Thu, 29 Oct 2026 16:44:43 +0100 User-Agent: Mozilla Thunderbird To: Vladimir Riabchun , Eva Kurchatova References: <20261021175410.2339797-1-eva.kurchatova@virtuozzo.com> <29f80a7d-9855-454e-98d3-b7b622433844@virtuozzo.com> Content-Language: en-US, ru, sr From: Konstantin Khorenko In-Reply-To: <29f80a7d-9855-454e-98d3-b7b622433844@virtuozzo.com> X-ClientProxiedBy: AS4P195CA0013.EURP195.PROD.OUTLOOK.COM (2603:10a6:20b:5e2::16) To AS2PR08MB9075.eurprd08.prod.outlook.com (2603:10a6:20b:5ff::9) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: AS2PR08MB9075:EE_|AS8PR08MB6358:EE_ X-MS-Office365-Filtering-Correlation-Id: 9fd29935-24a2-4cad-a4fc-08df35d38df5 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; ARA:13230040|376014|366016|1800799024|23010399003|22082099003|18002099003|5023799004|56012099006|4143699003|261022105027099003|261026140227099003|261021121427099003|261022075727099003|10067099003|261028144727099003; X-Microsoft-Antispam-Message-Info: FuCcbCIGLjHCaQY4v3tHJxCY/DMOhBx5OHA0reFBi5Pw5BVrrBjgwfTmw9scCngJt/KE+K7laK8Buzg2mwOltfPioXn4h6phEW+c7lkU5sVeegrHGzvc6Im67+/OqCXt7hKIddxN6zIa8BGJXWx6S4PJIPp7a3GsknHcVW+kQxxHdRsKqW1a91sqR7plQVYCei/mPm8jrwteu1U+2X2HKJpVHvNToC8V9ry/dR9nuzqTcXo0RRuxqf160O69bvKSyyDlzuEyVkfJnYrUwA54o9tlymQT2Y1I+WHeIDCnr25pdn0ENGgEUmzID+oF0V6PLha9eMVH/lVKss80Z3+y3d/pW/nci7O0sJYwc6jrkQVY0ut3WibE5cqX/4SuHsyGEVCIU7AY7B7mcZTjKldVLCbKdSD88tHcHV4oI0jPyz4weRqPDQhkOmHDKj3lxm98SOn8KxIS/5ZZDbOvEqVU3tgAVOq1J68a/CZe+nZ1pMeqh8B6ejXKXoJ02Jnb4vEoshVZQ2cRNA7xSsSXB3+Q1QfkOnx4Oz1TGUfkGnL58rz0mpuv75T5jNVFoZDCUpQB6fy1GokF9bAyMjYrIYsdV9q8wlQGAstJXZYOCXdM7fB6dCyraG0xPN+c1zEeX8nzK8Sn8JE1edkkukODfPNKfTaAXf2sLndetneA4TNVlVU= X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:AS2PR08MB9075.eurprd08.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230040)(376014)(366016)(1800799024)(23010399003)(22082099003)(18002099003)(5023799004)(56012099006)(4143699003)(261022105027099003)(261026140227099003)(261021121427099003)(261022075727099003)(10067099003)(261028144727099003); DIR:OUT; SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?dVU4MFNkQ2JtNEtjRytHbmRDY3RKT1Z4aHFzOVJQQ3Yza0svMTBSdWVSb3B3?= =?utf-8?B?MDE0L3FmbzdSZXhtQ2h4bHkvQ0svWVFJZUl2SkpsOXh1c1RiVSthWTN4UHo1?= =?utf-8?B?N1p2eTBaY0tVaUNNdWp0Q0JCaDUwYjJuTHZHZW5nOFo4VmU2YUFSMmp5Ymla?= =?utf-8?B?UUlDVmo2SndCWGtacXlVSzZuSGJ0SGw2SjVVbHpXYmM5a3g2NkJIODViTE9J?= =?utf-8?B?MU4weVRHWldpWTFoUGhEd0wvSTl0bS90S1g0M09pOVljWkdqU2dLbzJyTGMr?= =?utf-8?B?OEpTczdFR1ExNW1BL1NzMlpFMW5OYWhhY0Q1enQza3o3TnpZOVpmTkM4QlZM?= =?utf-8?B?Ui9hQzhSZnpDbk9iMHU0ZWZPdXZDbWlja1U3M1BoemY0bmdTdGFOVm5zbHc0?= =?utf-8?B?a0hGTXV0VWZUQ2hwNEJwTE4yZDlyNFY4MVJ6ODVvSnZ1aUdtWm9WNy95SStD?= =?utf-8?B?NWhIb2NvbDlyUTcvR1pwWE1PVjhZQmJ5cllkclRlL0VxaXN1QW04MW11Ujhw?= =?utf-8?B?RE9qdnpjbG1wb0xwVkpYY09xZ1ErL3N5bVI2WmwrQWhVaUcvR0RhQ3c1NWVH?= =?utf-8?B?bTdGeU9IcnUwUW5XdmRtOTVFaENWRGQyWC9iaUVHbTYrUGcyU1dGbFI0a2t5?= =?utf-8?B?VlJJV2d6SUxqT0tvQXNnMTJDYzE5UnhkZzdLVG56S0hmUHlKbVQzZmgwc3NI?= =?utf-8?B?a29VVnkzQys4NjdHOVR4U0tXUG1xSG5zYUQ0UzdpUmI2cnE4aWJCTjdwOTZk?= =?utf-8?B?SEI5TzNmUUFQV1pWQWZrR01OeFFaZHM1Q3EzbmxIV1UxcFRpQXBiYU5iVkZt?= =?utf-8?B?a0JzT21kcXBpYis0WGt5MEd6OEQyK3V1QWNFU1ByUDdKWDlmNi9LYmhuUUJ6?= =?utf-8?B?U0o3Y2lCdzFEM3JFMXo1dEFnZU9VTldwNm1EUUpjN0MwbkllY2xmMlVvb3M2?= =?utf-8?B?YXc0c21zTEJzVkxwNXArZ0Uzby9YUWQxVWhDL2Frc3kwVnA0SkRzU3E2dlJT?= =?utf-8?B?OEMyTHpZM1VXbVRya1A3VEhjbmlWQzRDRDJXSVNMTHN2L1RCdDlKOThTcy9o?= =?utf-8?B?YlNUM3RVU0N1dG9Pd3drc1hVclhIUWJWVXNqWm1tTll4eUoxUWtmN0J2cE5i?= =?utf-8?B?a1Y0UVEvNzRpWXpjaUJUMnNEQVpqdjJQVm1IaEY1THdKY1JCeWxHRTNPaTF0?= =?utf-8?B?YndDRGNrbEhGQnlrcFdXRFE5bFVIWE1Xb1B0RHUrWEtneXFHcnJaa09TWEtV?= =?utf-8?B?dDJWOE9EQTdPQXNud2JlUHlWWFdXYnJvYTN6Q3luOENTVys0b1FBaysrbmp4?= =?utf-8?B?VmtTRU0yYndXeEJ5bUxEVzJjVmxKVUFBbmxmOVlrOFpNdVJDakdlbGZJMDBO?= =?utf-8?B?alVqSVA5ZWtKM1NGMFNoY0l2cFdCa2VJYmJjLzBoRGVrYTlaSHJrdFREL05n?= =?utf-8?B?MFpDWXFveFJJVmlQTXBtUzRIOWhQZEJybUIzRXloajZaYVZMZXBjbjRNNlNK?= =?utf-8?B?ejZ5Y01zRG5wYnJLMVFNYkZIYXB2Rm4wQWw5cGFIZ29Nd0xEaUY3ZmlWWXZx?= =?utf-8?B?TXJwSGF6b0V1ZmJEbmcxWTBkcFBzcFllYVc2OUZkT0RlMGNLOGJPV2hzdmZC?= =?utf-8?B?cFNBSUg0bmMrK0VsalN4ZUFDWFdMamZWUDZpUFN6UkZIMGVYWWxxdFRoSzJG?= =?utf-8?B?Ni80Vm1UdnFtekRuSkU0eHdrSjN2aTdGcUJUbXkzS0VhQktxaEJiRmVHYkwz?= =?utf-8?B?Q0E5UGR2bFVuOFZPbFlRbEFQOENoaHZJWU9oajZCNmYvMDY4eDJnd0h4NUMv?= =?utf-8?B?azNWdjY1aUhiazIzYStoWXQwbjZoRkI4bzlLd2FlSnN2QndEMkdOUVI5dmFt?= =?utf-8?B?RWppRmNWbnVNSXg2eEJwSDljYSttemxBenpsYU5aaUJISk9YOHdIYUMvbFR2?= =?utf-8?B?aHp0OEIyZHozeElTVUFDRDhIQU0yTjFMMDBHb3ZidlQ3RXh4T2g3dVVha0hS?= =?utf-8?B?N3EwMVV0QjBqOG16Nnluc2pyN3J4ZXFGdWkwZTFqaDJ5Rms1Q2JVN0hpWk1R?= =?utf-8?B?K0FieU1VbHErQzFUbkxQTExVTzMyVlZvZUVYWGp4eS9HTUpaYXBqUEpKNjhO?= =?utf-8?B?WUZZT0VTVkt6TFpXQWFPem55VVFORksvRU5aRTZ6RTUwdHlUbGY5VE1pcWtD?= =?utf-8?B?eXNXZS9yb0UreEovaVNDSHBQNlFwbW13WWV0dXNLMEdwakIzYnRsaEd3bk5J?= =?utf-8?B?T1A2L01aWE5XNzR1RmYyWVRwZXRqYzFCbm9kTFlFNE9PQVRpbWRlVWxxd1ND?= =?utf-8?B?MVFxY25XV3k5aHNsRzZaRFYyZURUb0dlNGFSY2wyRFdGU3VVSVE5Zz09?= X-OriginatorOrg: virtuozzo.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9fd29935-24a2-4cad-a4fc-08df35d38df5 X-MS-Exchange-CrossTenant-AuthSource: AS2PR08MB9075.eurprd08.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Oct 2026 15:44:44.7931 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: afyF0qW4IgTBh7J7rxpTQ0aZ0S2/VY0nswDhLYEmLhi2W2K1rorb2z5HXuzDV0EP2myT2koKK8A0SXy2835ZTg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR08MB6358 X-OZ-Fwd: true Cc: devel@openvz.org Subject: Re: [Devel] [PATCH hci-8.1] block: let container root set the block size of and flush its device X-BeenThere: devel@openvz.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: OpenVZ development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: devel-bounces@openvz.org Errors-To: devel-bounces@openvz.org > Is it possible that some evil CT user can spam flush, keep mutex most > of the time and prevent some host actions? No. bd_holder_lock is held only across the holder pointer test. The ->sync branch goes through bdev_super_lock(), which drops it before taking s_umount and running sync_filesystem(). The other branch unlocks before sync_blockdev(). Nothing heavy runs under it, so mount, umount, freeze and mark_dead on the host are not affected. > I'm mostly talking about ploop devices passed by vzctl. In v2 those never reach the ioctl body. libvzctl configure_disk_perm() grants CT disks (root ploop, secondary ploop, physical hdd via use_device) r + W, plus M for non-root. W is "write only for mount": the BPF program in bpf/cgroup_dev.c passes WRITE only when the request also carries MOUNT. bdev_permission(BLK_OPEN_WRITE) has no MOUNT bit, so blkdev_admin_capable() fails and the CT gets -EACCES, same as today. > The same question regarding hdd disks from vzctl: can't we break them? Even with a plain write grant, no. They are mounted by the host. BLKFLSBUF hits the fs holder and v2 returns -EBUSY there. BLKBSZSET cannot get the exclusive claim the mount holds and returns -EBUSY by the unchanged upstream logic. What v1 actually allowed on the CT's own ploop was sync plus invalidate_bdev of the device under its own filesystem, i.e. what syncfs() on its root already gives it. v2 closes even that at the device cgroup level. _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel