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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?kGwbsdh8zYNSiQihSSHMNabuKts2pGKBj7EWBUGsDhAcdf4h2dK0WI+sFgdZ?= =?us-ascii?Q?VAnImQmJlJ3DhrX8OCtLh0XnXhhCIsRkqQKIKohj7+Q0IhZNFuVjEtY3J1HB?= =?us-ascii?Q?Pp3pulOQVLYpxNZ9GZYFO+oM67WdwPrKoEvExOTyaDD0tDP3tCUQMjnQLJVD?= =?us-ascii?Q?u/GcIHqQ/wqwxWBNHcT6lDLDHcDe0IkWwhmO43HzEqiVkbtonnuVkju9PbM6?= =?us-ascii?Q?yNDYCIhx5Zst9ARXVWULlfqImaKyJzQtGILakLfsYL6eNIk4FDY4ZFsgzjX2?= =?us-ascii?Q?G9EIeXgQPgi89OFiSPOkLzyWyTJ5Nm7OZEq7kqkjiyzqtK+9WxGuUrdImd3B?= =?us-ascii?Q?igY4IO2suEoGVDAVpL7k1vvSLPfvWDByquUXaRUT+SS4/QPHB4k5xCXU7nPe?= =?us-ascii?Q?z7/Q+V4f/akAGZGF9T0cLVPe+Z3qQWNWIxz53AKnuBYRAVdB++YFIY5dGP5d?= =?us-ascii?Q?Y7W9rHCKnDnvzRshA+0O4ez+nBsKSIC90DcAozFlpK1UkIDtXsAvF/Dmejcq?= =?us-ascii?Q?52p15IEegD56lIh1+G185CPB0866kZbh+tWG7vfPTiZsIzmFs3fDXjTQgLNF?= =?us-ascii?Q?tOZ2QdTv9r/1NSBoPnwAeQ7rmAG/p+chMC522katVIhUkPNVlty/kH1+CBEK?= =?us-ascii?Q?TTSHFGcKdgvUK8BM7PKARlYIruXdzi7MNKWwYv2wQGIXPnXtLh48QuP5k5cW?= =?us-ascii?Q?/vh1FSXzVHAW/MgCRPKv9eauPFC4288mb82KQLg0C/CyZ2IJEPlyJqFdJaoe?= =?us-ascii?Q?qmoh/l3YixAw7CNCz2tmmW6uFj6PVhF65a88XLZjM5DXkdFbDaRda6HuEJGm?= =?us-ascii?Q?3+gO+KMHV7LlPdcsJd60TGMlxgx4LXTcTODWZSQWSc/oUEu3yyfo4Y7sgzGt?= =?us-ascii?Q?6X2YWRhJ73kx2lpJaBlaioZNHmImOqu0BOXoU0tafUikxsEXtg0mFaiWXCld?= =?us-ascii?Q?BB4ctTKL7Tjk/DyUwIZA/v3B2N758jOmRUUnKjEAYy7C8XkrklgTBKP1l2oI?= =?us-ascii?Q?tcMmHLRX8RuDJD+4WEcgjJFU+dMD6Ts/otzgm9L/ODP2FsttwYcdsqt9KEzB?= =?us-ascii?Q?7M/uiDLcp6AVNB9CeHXP8ARHOyuaYHIgXxUOJ862LNASdTt/CSj7iuEva9EF?= =?us-ascii?Q?aUbBe86vdsnUas1GGpv3/Tg42dM8llcqfUWewMOFa4OippLTKez1ShqbBxnJ?= =?us-ascii?Q?ZD7R24k2Rod61uWj3jKLcvlf4gjnKJ80OQkfwt6a2Ujler8+XvinItMcNzGQ?= =?us-ascii?Q?lkxBpDRLK1Wp32H8lwR4tjGbhIZc0ok9f0KGdBSTjXa1PN4Dm7KYJuFO/qa1?= =?us-ascii?Q?wYBuIvLNlMlN3DK9wJu7bycD/spFlwX9dAb50yd3NZpurX9BOl1rCaA9/FvM?= =?us-ascii?Q?PXK/JPsNCtLAZeoz3xDZTe0M5KinxWagGd+9ifH/76gX6DntIWMQ+3OTjIgI?= =?us-ascii?Q?oNgEKSmMELxccHFUL1EBZaA5iSYzcqoJfKGk9YO9vrdADgJAifhPp3w6CWap?= =?us-ascii?Q?p3Y+ppYgS2VCHvc4ZcvXuVpPCht4X31vGD01f59bBPfs0BMZy/BqleYnZHLP?= =?us-ascii?Q?V+5Z13Z+VIbDFebced4=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5b0109d0-e9f0-4d48-042f-08d9f145dac7 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Feb 2022 12:14:17.7179 (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: K95KZpzMxVvD/1YAFjbaJTZmmmynpd21KEfCzF+r+OUU/rE+nRaxey2Ku/eVCRNP X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB5606 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Feb 16, 2022 at 03:17:36AM +0000, Tian, Kevin wrote: > those requests don't rely on vCPUs but still take time to complete > (thus may break SLA) and are invisible to migration driver (directly > submitted by the guest thus cannot be estimated). So the only means > is for user to wait on a fd with a timeout (based on whatever SLA) and > if expires then aborts migration (may retry later). I think I explained in my other email how this can be implemented today with v2 for STOP_COPY without an event fd. Such a device might even be able to implement an abort.. Jason