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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?nytQ2lsrNtFox0/YuSIC/DqZCYycM6e97MdlAvhcKwtS53u3E6WLWpi3xZBy?= =?us-ascii?Q?MTt+rmv4gQCO3qfxKE1g4xunDeaEhAsQAXI2tNjLrEehs4rlFJv6HDrRlLjR?= =?us-ascii?Q?jKB7kRkdQtet4ri93ehaHp5CIZMexBroUzt1Sgo+DiHqE6qcFMBgkaVUP3CX?= =?us-ascii?Q?hkV0Ee84k1yuNRB2YoBJjHw25U8nkp7wPlRGgD4J3hJmFR0L/7uOuZHi2m0s?= =?us-ascii?Q?6itdhw1PC+UgXOyJVGdud74pLZWXfQ6bNBVylF1D/7C5+YuW66/AJZFxJMYb?= =?us-ascii?Q?dRC+InfM5Q46xV35IlVHzU3aanxjD++wS3jjdjl0N09Tg1399XxikOmgcdgX?= =?us-ascii?Q?ulfTMg6u+O7PHnqkN/MWWqXzArMq3m/RHP0tqtOJ62nA7DIZvrfabalVaPGf?= =?us-ascii?Q?tk7gUwRuDnGmEB4mdcUqF505xkSqupufqolkGoxD879lxjb6ZZBPGfqiqgG2?= =?us-ascii?Q?lpFupPzjSpFwIS40AEukhBd/l+tNXLSPcHm+c3Fk/oX7tGIfVLg0idHnhUTd?= =?us-ascii?Q?KnMqCvBSgopKjUFRmwLMJN8jakrVEVMEd6wmNaRDUVg7wYMv2iID3ho2I7LP?= =?us-ascii?Q?28cBVTrMEN7FdaFHmZgk+E+Lu9X4PPG93HRXpejGFPxgvMFosMooLF0GTK+n?= =?us-ascii?Q?GI5AKD4EooPn87G85x96NR/J2pIIds/4iOaPESXoG222gR61/oH6oKWdvhrY?= =?us-ascii?Q?ZcJbKcTgVso6fwQgK9ATkKdVRES5PamkgUw/AjdNURc/CmnB+CDsJRK/55jP?= =?us-ascii?Q?riR2BUXbqYdAV5Klxr6FJtmnErQ0NyFPFlB1o102EEpIjO0gK2xXMO9O7CBz?= =?us-ascii?Q?zSCJ3KfrjGc/cFUaYQc754FEpW7t34Us9nGKwrWGdQhEwiZUurKlOOMZomQW?= =?us-ascii?Q?UEV36R39f30GUIV0F8+KBhPh+ZJ3OX+Be3YV2lYJbg7htyaQ/yB66w5IWyDL?= =?us-ascii?Q?drTCr8mw+3SWTNsKmwCvE1rhFzbHAFLkY8rZ3n/V0CMKSRXN2lY/rGAP5pJJ?= =?us-ascii?Q?0Vke45oj0KfDcKRv5R1BPvXYf648+cm071qDoZ7JFzFPgmtQ0mjXmBaM1sYf?= =?us-ascii?Q?0oQfiTmyzLM8J2gpDR+qkDbAU9xPqnrkLl6LPWt0/2/dlc4bOTqbpqZb2TjZ?= =?us-ascii?Q?/HRwRDjiLe2dpjqMXiRDtYaArNWOPHhnhRYA/UA4FsLuMCugzXkhWg2XDFRv?= =?us-ascii?Q?o6pONJfujFmv7tl6U1Wac/mrF6IxtEP9webY6rxV5xqQpYCg/LABeM3Dvpim?= =?us-ascii?Q?koiMIqR7gBRPo7iElQyDhHLjN3yE2jEWFBd4EAB/Q9FJeG4nv2paWmZALVY6?= =?us-ascii?Q?8oYzZGLgBGvaMpDbjjfweh2TAERezYFr93A8efxGkfYUdutIne+Rvzkhtts7?= =?us-ascii?Q?cqG20QtV2z7XOVesZEwkHEAVbDoeQ7oS5SzYJg8oagUkYfM0MMUdkPO5+6Cy?= =?us-ascii?Q?zyv+A2gA+HixFEYIGsYFCa+yN0ZdnU8vDUvD1rberGZCpIgIW6KydUBLWznV?= =?us-ascii?Q?HryH1EI0jl03erYlzPi8dqVipmZCiITj521tmmIeRDzPt05SZzx98Qvjf8rS?= =?us-ascii?Q?+hagqnquWgk6VvJCJ681ugZ4em245fFiyh6ZKU+0?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b9531912-2fe7-4d1d-323b-08db2adb667f X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Mar 2023 13:43:21.0434 (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: RQXWz7fGDBeHXJ93C4GTiw7d3t85WDz6AQSVgUhkpVZ7yc1um1MKT2XkwYaJixIB X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5389 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Mar 22, 2023 at 01:33:09PM +0000, Liu, Yi L wrote: > Thanks. So this new _INFO only reports a limited scope instead of > the full list of affected devices. Also, it is not static scope since device > may be opened just after the _INFO returns. Yes, it would be simplest for qemu to do the query after it gains a new dev_id and then it can add the new dev_id with the correct reset group. > > I'd probably use similar logic as the reset path, if one of reset > > group devices is open and on a different iommufd_ctx then fail the > > IOCTL with EPERM. > > Say there are three devices in the dev_set. When the first device is > opened by the current qemu, this new _INFO would return one dev_id > to user. When the second device is opened, this new _INFO will return > two dev_ids to user. Yes > If the third device is opened by another qemu, then > the new _INFO would fail since the former two devices were opened and > have different iommufd_ctx with the third device. Yes qemu should refuse to use the device at this moment. Jason