From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from PH7PR06CU001.outbound.protection.outlook.com (mail-westus3azon11010063.outbound.protection.outlook.com [52.101.201.63]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8670337A839; Thu, 20 Aug 2026 16:56:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.201.63 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787244989; cv=fail; b=i033CN6LyL+wKhUpudxMOORv2dqMNyRMs8i/Z7pVrBl40Hfn4QjsZ9SPN4kiSuizmhF3qvPnjA1rFpDYmTNvsUJY95kImaVKPIPoG0NuYMX5LXxIO14U2/ZPbXANIJ9suOd+JS9G/nWEUMhiqYGjGiTNgREL7fsNHFeSGaVzl64= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787244989; c=relaxed/simple; bh=h6mv9v3BdUpIDV1z7SL7//aoqyky6kMIUVf9CtmTQL0=; h=Date:From:To:Cc:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=eV+fKCrR/rhvjJsnHuFMyCHzeIXW3Qzm9bNPf+Ubx/hpg/EgoWCJgWzs19aj5EHll12hINGc8YGR+Yk/4rtRxiWV/GAqAHh8S8UeeZqRIcm1onu7AT/6tCmTTxbze+bmZTLBeVU6yG/qwhoKMfdfe4gS0qBVSJBgpvDmh2lrN10= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=Z+V47ETw; arc=fail smtp.client-ip=52.101.201.63 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="Z+V47ETw" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=Kl6GXsJz3vKw38yk+XtJCl4jh65+99XrftYm6UVw94wPbQ2C6kZwr1PXEUhwnhEc6bNuffIAsi1qAQQyQjCmxfeXLhV/OzyMQQVjr882NC07fMCHNHz4ojlEQ3RLxcdvw+4Y9RjSSMQnfBM3MNjCo/ZH8Fbjh+0PVfcBUp4JL/hVe1Azr2hva3ierJLI4JjY8DE1yyS5lOyaKWolbkiZ1PCWhypLPegwOAZ0eHWZxdbObc8wJ9qLvM4falnJbh4ODb5cPwo9QTQBSffODEbfzxrs13EPNIWIQ8wVvw89/eGeC9OrgbqXfyXtWdQSnPuQgl6txFM2LTeqzgx3B8ml3A== 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=S1Rgk3rfpmXzDH86F2FS7kdD9r2K10EjW8nbWDaDurI=; b=WITyomwpMNfrtKc9x+SbNfy0A7NBtuyjHNIUDxbXTXdKZmRBINiCZGH17L7cA+cIZcJzcCKuY+bl32xp5smgmrOnhDGhuHA3gK/BYGne1x3wLsu7m2RwvXg7n6VRyQ6v/WsXp6+wFO6tQgSqnWOm+mnRdisAPAOkZuGpl68o9A7Q+1bkGbUfH4Ee51JnVQ+4jnfXWBdF6qqu8Hjfr1hm3MJiTOueeKeEw8CVnRwrFppbe4oSLCk7xp4QyQa49G3iLLl6lIUynuQ59E3yoaYk38H0BVG8CMdrC9OxcR9KxM8yt2cKdMF6HcehT9s8RJIM8BVTKRIyRM7jk8NHKBy/vA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=S1Rgk3rfpmXzDH86F2FS7kdD9r2K10EjW8nbWDaDurI=; b=Z+V47ETw/57PRDPoXBVCTy+YXxvC+veBeQykXfCqTM895i6XMB/Ax998gMau85nG3FfHjNSd7EeZsKxsCuONP/fLuSrSvbwtjMkqUxchNzULrRvGI9sRqPlsDFWcr/N+9YNS7MhTQ7S5g6pM9wwB6peWYH78Zq4dL8BCdcF/kgp+w35Pi959+jN1YaI5KJ8p/Gb72i3HUm14kdNrPEUFRz6jGbIlVgcIKTsXCxooRijLS7uYCkP9zd6LgfZCreEzVEeqzZVAh/EsOfWrL1xm8/k0sN1XPDlotnBnnaA3+c3K+tkA50uSkERNaAHSNz/ysum7LxeIIeSKxt0M9JytLA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) by DM6PR12MB4418.namprd12.prod.outlook.com (2603:10b6:5:28e::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.339.10; Thu, 20 Aug 2026 16:56:22 +0000 Received: from LV8PR12MB9620.namprd12.prod.outlook.com ([fe80::299d:f5e0:3550:1528]) by LV8PR12MB9620.namprd12.prod.outlook.com ([fe80::299d:f5e0:3550:1528%4]) with mapi id 15.21.0339.007; Thu, 20 Aug 2026 16:56:22 +0000 Date: Thu, 20 Aug 2026 13:56:20 -0300 From: Jason Gunthorpe To: Steven Price Cc: Christian =?utf-8?B?S8O2bmln?= , Marc Zyngier , Sumit Semwal , Thomas Gleixner , "T.J. Mercier" , Benjamin Gaignard , Brian Starkey , John Stultz , dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, Jiri Pirko , Marek Szyprowski , Suzuki K Poulose Subject: Re: [PATCH v2 4/4] dma-buf: heaps: Fix shared system heap allocation rollback Message-ID: <20260820165620.GA973874@nvidia.com> References: <20260820150034.88729-1-steven.price@arm.com> <20260820150034.88729-5-steven.price@arm.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260820150034.88729-5-steven.price@arm.com> X-ClientProxiedBy: YT3PR01CA0047.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:82::11) To LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV8PR12MB9620:EE_|DM6PR12MB4418:EE_ X-MS-Office365-Filtering-Correlation-Id: 6b7b2034-f2d4-49cf-483f-08defedbf679 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|23010399003|376014|366016|1800799024|10067099003|4143699003|11063799006|56012099006|22082099003|18002099003; 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:LV8PR12MB9620.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(7416014)(23010399003)(376014)(366016)(1800799024)(10067099003)(4143699003)(11063799006)(56012099006)(22082099003)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Y8Cj/Vjb4D+yErJTNg13TsklrVPx0Cbv6Yvu3+ZYrHgvb28Xc/CyJ7K0POBO?= =?us-ascii?Q?JGfAB8TFy7uBiWkZcxLWdTC+axhu8RHxW2zA4Wh7aYw9hGkbONQFTHEf2DBh?= =?us-ascii?Q?6WIY5tfZkAKiQ1DH/IbgCpye3xq3ch1LyKACHLxaW0WjEpJ2C/n4K0UNum1A?= =?us-ascii?Q?nEKbQ+zz/yA0U6aNlIJeQY8AJysLqkidySyupGU+ddZY3+IhgFtEaZFGF9Ae?= =?us-ascii?Q?hAbjHHL6n27MyJfUURDs12et0sf4WsAdGGhqqUcJtfCycfizhMSwTyifTnKf?= =?us-ascii?Q?mUiAXM+v3V1ACvy3pn9NTKU1ngOCVtU68c+zLQN9fdgN/lZaJnLVOHPULKg0?= =?us-ascii?Q?mKDcSklqLca8TaFfzfpSAlHq3cdxVZY688SQYOK01mUQLf0Boyh9o1QR1E94?= =?us-ascii?Q?V8ueTs093mVVl3Coxt6HEDeNAFbsqfZCxXuqt+IFlFRaeTxi3lJiAjWt1VUU?= =?us-ascii?Q?bLsUbaDNQPL+sBel3iY/+zx4dce7BLe9y8yrW+ws6pEtF3LtFKxd/XOWZT5l?= =?us-ascii?Q?VFf0zeqBKuMpqLknprmCJyr9Ye5nOjh2tAnkMjk8BgCsvVByh75bdf6dMn57?= =?us-ascii?Q?Msq3/XKZU/3cE8R+KIHWq6zKSsLhohH6pwwolMP5N8nq50I4w/BKlj3HFbS0?= =?us-ascii?Q?LRCdZpsOVxKUfZNUwiWgMRRYcCR9/LYTA2U+/3Sk5b7k+lLgAfwtQUxB5/wE?= =?us-ascii?Q?RR/gGUnueuAnEv9aAtLKzl7umeNtacJpBFRLFpGF1WdWBcTDm4//8wt3OHrq?= =?us-ascii?Q?kLH7vkzAo6F5+psVueqRxMN3zYVDN+rl6del6iMg8eUzmjvOvZY6spy4nMb6?= =?us-ascii?Q?NJKyaxghTwbpk0jkBI7S8JmZt0qro5YC718WpHhWYRrU1LrccqM3/U6Y4JXo?= =?us-ascii?Q?IUx++1ZGuMR7J+3Vqwaq5Q4d25sn+3f2tJR3JKXCcr1gbiiIu9HkI9zc3OHA?= =?us-ascii?Q?P21udS/FLAoaena4WBHyONKJIUEKrzTXjrtHiWfdHkygHcVrbWPUWDRxc7RG?= =?us-ascii?Q?V4Ol+HQ7PrGu9UNSMhWgbyIgFGMQwaUHEqMCr62mCW5bTkj1I10Mhawyh7HF?= =?us-ascii?Q?cwGgQSS2lf3r5BvkUUyE1oGryklVr2meaLTGPUmAFSJpZl2Pw6lKZy4U5fRG?= =?us-ascii?Q?xZ8SMPLlWLPePgi9BVdHvBah+SYxxlXrq2oMhWfbUYDp9SAh4ECqqmm8gAw2?= =?us-ascii?Q?E8zXenCdGnvdfgTLbFGK73SbYS6kTzUPHYU/5lVkYod3Eo5ojN28BrxlZoyx?= =?us-ascii?Q?E4prxOWrLr220c1OsdTMjqioMGT71BXXscYK9WPa1n8yanadQRpkw6ZZEGIP?= =?us-ascii?Q?hzX5KQH0geD2z8jxQgagFS4klAqrEj0rf8EeUHxctieeAx95r3dCPIEkFRft?= =?us-ascii?Q?bnWAKwGMinDyn/91Lzp9p3+lMivH6318esh0McHxLbGbI9sVOwMTVELHmJns?= =?us-ascii?Q?DKdRjl80/F3x73NVm1DxlnW8SL2uXXhBrVEpMMH0juK6AH11CXLawgF0Ld41?= =?us-ascii?Q?KX0FJT9O3zGEufy9nlWlRVDGS7Q80N/aMWH1LyOlrlRrRjJV9LoZDckELwZC?= =?us-ascii?Q?aWpnVo5yw8RysX+ysciap8ZJmiPD/P9axd1P5iFMfUZ++sPrTsWcLDroHLzR?= =?us-ascii?Q?CWvg73sd84Iwx0uO9d9jJx7SoqN9pkmxYpS1yJcXzozCDo3PIUp5eRYwo60Z?= =?us-ascii?Q?K2kQVLPLEP+q+CDDpT+HWVfPXd1Tdn5SDZy8jN0aNW7I2TsB?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6b7b2034-f2d4-49cf-483f-08defedbf679 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Aug 2026 16:56:22.1742 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: uUJpNUjggZkxLVcZ4E3eopEpAJyk2zm6TMOYkddsgT5XlBlK2H41CS5P3mfFGWZq X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4418 On Thu, Aug 20, 2026 at 04:00:33PM +0100, Steven Price wrote: > If converting one of the allocated pages to shared memory fails, the > cleanup path attempts to convert every page back to private memory. > Pages after the failed page have not been converted yet, so attempting > to convert them back can fail and cause otherwise reusable memory to be > leaked. > > Count the pages converted successfully and only convert those and the > failed allocation back during cleanup. If converting the failed > allocation back succeeds it can be freed safely; otherwise it is leaked > because its state is unknown. Allocations that were not converted can be > freed directly. > > Fixes: 78b30c50a7ac ("dma-buf: heaps: system: add system_cc_shared heap for explicitly shared memory") > Signed-off-by: Steven Price > --- > drivers/dma-buf/heaps/system_heap.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) Reviewed-by: Jason Gunthorpe Jason