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Tue, 21 Apr 2026 06:20:01 +0000 Message-ID: <3d19f4c4-5173-4879-b2ee-7bdfb8aeee53@amd.com> Date: Tue, 21 Apr 2026 08:19:54 +0200 User-Agent: Mozilla Thunderbird Subject: Re: [RFC/POC PATCH 01/12] drm/amdgpu: add SVM UAPI definitions To: Matthew Brost Cc: "Huang, Honglei1" , Alexander.Deucher@amd.com, Felix.Kuehling@amd.com, Oak.Zeng@amd.com, Jenny-Jing.Liu@amd.com, Philip.Yang@amd.com, Xiaogang.Chen@amd.com, Ray.Huang@amd.com, Lingshan.Zhu@amd.com, Junhua.Shen@amd.com, rodrigo.vivi@intel.com, thomas.hellstrom@linux.intel.com, dakr@kernel.org, aliceryhl@google.com, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org References: <20260420120739.1811731-1-honglei1.huang@amd.com> <20260420120739.1811731-2-honglei1.huang@amd.com> <50d13ae3-be27-4b79-91ef-e1b386054943@amd.com> <54bb7286-2ffb-47f0-b37d-83b5c39ad9a0@amd.com> Content-Language: en-US From: =?UTF-8?Q?Christian_K=C3=B6nig?= In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: FR3P281CA0179.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:a0::16) To PH7PR12MB5685.namprd12.prod.outlook.com (2603:10b6:510:13c::22) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR12MB5685:EE_|SJ1PR12MB6243:EE_ X-MS-Office365-Filtering-Correlation-Id: d9f717c4-520e-477c-1d90-08de9f6e04fc X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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The user sets the preferred placement to Device A. > Device B faults first, and Device B moves memory to Device A via remote > pull and can access locally via P2P, scale-up, etc. Avoid a double > bounce once Device A faults. So you basically tell the device as soon as you want to access this VA please push the underlying memory away to a different device? I didn't thought that would be a valid use case. As far as I can see the only thing you avoid is updating your page tables on the faulting device twice. Thanks for the explanation, that was absolutely not obvious. Going to discuss that with the team on the next meeting. Christian. > > Matt