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Fri, 16 May 2025 08:44:12 +0000 Message-ID: <0a890d19-27a1-4525-83e6-cfc082dfab37@amd.com> Date: Fri, 16 May 2025 10:44:07 +0200 User-Agent: Mozilla Thunderbird Subject: Re: Sharing dma-bufs using a driver-private interconnect To: =?UTF-8?Q?Thomas_Hellstr=C3=B6m?= Cc: Dave Airlie , Simona Vetter , dri-devel@lists.freedesktop.org, intel-xe@lists.freedesktop.org, DMA BUFFER SHARING FRAMEWORK References: <703610a4db0324db05ece8e83fff864717c2e6c2.camel@linux.intel.com> Content-Language: en-US From: =?UTF-8?Q?Christian_K=C3=B6nig?= In-Reply-To: <703610a4db0324db05ece8e83fff864717c2e6c2.camel@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: MN2PR16CA0023.namprd16.prod.outlook.com (2603:10b6:208:134::36) To PH7PR12MB5685.namprd12.prod.outlook.com (2603:10b6:510:13c::22) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR12MB5685:EE_|MW4PR12MB5666:EE_ X-MS-Office365-Filtering-Correlation-Id: 8048866c-b221-457c-87b3-08dd9455d4fa X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024; 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Nothing visible outside of the xe driver or its > child driver. As far as I can see that should work and we have recommended doing exactly that to multiple people in the past. > Are there any absolute "DON'T"s or recommendations to keep in mind WRT > to this approach? My only requirement is that you write up some documentation (preferable either in drivers/dma-buf/dma-buf.c or Documentation/driver-api/dma-buf.rst) how drivers should do this, what the implications with the rest of the DMA-buf interface is etc... etc... The goal is to nail down how to do driver private interfaces without breaking interoperability with drivers who don't participate in that. Regards, Christian. > > Thanks, > Thomas > )