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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?IMisncu2o1GMMcLynSjyuQJU0RpFa+mAiU/lLu+sVG5gki2eJxIdKOQ/G3zC?= =?us-ascii?Q?42/rCHVhY1CGgoHr+Bsj4745AzC0mxz8aAPHmLfq0j9kNuvwFkJEX95lEK3/?= =?us-ascii?Q?/2kj25v0ifyjBo/0xvpq4L1UM9ZlsfqjTJMHDSSUdJAxi26PkCE2mUmJbmYI?= =?us-ascii?Q?9aMkWCtEpsw0h5XI6YrUlfuWAulseojCrCOTxKV1sfNyrjlyUgzU4FRuAYNA?= =?us-ascii?Q?Mqh8s9qsc7HTBG5vRJM7bhp/JFNBT0ftGBMnt/jSRyld4rniaigRynOVgfaC?= =?us-ascii?Q?gbG1/3rkZBu1/H6Ej8wSkienEy2AsMc+XYE6ppwL5lLFWRLKSDvrKCLEUfkA?= =?us-ascii?Q?zaYWKzx8/X5Tv62RkkRx/2X5XLubVMUxI3he5lNCsiKhYbKoLguMJEE3732F?= =?us-ascii?Q?8/zFRfsqu2esckBQuucdrN3VGSTkBw0uk5nHPaEtgthQGAsrkn22MTIjdM9m?= =?us-ascii?Q?goSYvX5zhQVZkO9c2/oQ04W0xugjOal1oiQrh7BftxUDL0FvYDH5f6knBWH2?= =?us-ascii?Q?c6gC7GwmIFRK5UkUSm9VaT2zFLYmFTdOSeGNZ8AxrJLDaAHnSMsX6jlxl7vx?= =?us-ascii?Q?MelBrIAY0jtQlHiGEXNsbdg1wU/cd+hopwL+ZeFYZvm3VwskCjtR5FaeAshT?= =?us-ascii?Q?yBPmK5yTvEwv6PvwTDX+WCwzaL/KriYXScmSKvFKO7PabKZzEg4xJYZskmDP?= =?us-ascii?Q?vPlJknwIkdqyDZJDDyKKmra3ycirY+Ba/HZ2r1PQh1hzD5Uhsqi3smcM+goW?= =?us-ascii?Q?cGk8V8BTfA/f44hFldTajAfp2oUYiFsqqQLhK3GFowmwV6bSVZ2ne5tPGiLu?= =?us-ascii?Q?rWBI/U9BOsIztSzbcKUW1UbN1zS2YGQVrvJR+3xZazCb7FCt7tb8hWtueSb1?= =?us-ascii?Q?a0d1/n6EIlZWOmuPrSbd59Eknuec2ZxEpuMwhrCuyA5ojhkYfnkIOQb+qQ7Y?= =?us-ascii?Q?V3sYXOX8N6nVECzmld8OFxeM7KZa48F+OgKy4lSR4j5EXcJsSRUDKb8IROvT?= =?us-ascii?Q?X0Inz+/Sy+siWGABJjIYhtPfdwCR+lMEAcz1eMabLGSZsIoR9VV4pjTk38Bl?= =?us-ascii?Q?6Zk92tRwYUEM1Mc8azfZNnuTseC4wFaxw94/EgZn7AMihtH75VZWJWKKX7Nw?= =?us-ascii?Q?9rs745jiUnV7a406/Zv7biYfLmoNSgsCPLSZ+hldRL4kZ2fK5gF46faBxZ1V?= =?us-ascii?Q?qlK77V0BjvqfG0aF0oJa6s9NpPKkybs1XQZJxrhANIvj2oU5smUJGs80yjHp?= =?us-ascii?Q?pg0DBAQHlY6qcs1CivFBnTty3Cmfxi+gb/3gcvDfmrVWbVcKvcb+jI/0p2+U?= =?us-ascii?Q?7DAaKK/X1nGAv4R33km2zYT26brmybVskzj9D7IJzYXnsSyDfcD64bcHFD9V?= =?us-ascii?Q?25Kb3DwlWWgq91O/3p1VWpRo42YDRUYx7+Gpj9SVOXwpE1hvVRTmS5hcti0H?= =?us-ascii?Q?zBGIM0nyxWp5+vNziSJeDEsgtPTZ3gb1QGAvR9B5kQhsvZmbOS+j4kTJUDjs?= =?us-ascii?Q?kEnziM/7ylqsTRCUOOH6fwWR/acyBFfuXxn1kuYI5igt/6bRdvtgzXsfID2o?= =?us-ascii?Q?+nu4v+l2TXeFSUjb56Xj1wq6/hyaZNAxRCd6KgQS?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c79b8948-4c76-4d25-09f7-08da9ceff7fd X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Sep 2022 23:12:49.9581 (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: FiDG2EHXOZkEac9wp4rW0AXUJSqkiqBE7r0BN9FV4FlkB48TuCnwuPMCIJX2Hal4 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB4936 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Sep 22, 2022 at 03:23:38PM -0600, Alex Williamson wrote: > Well, we don't really need to have this behavior, we could choose to > implement the first two patches with the caller holding the > group_lock. Only one of the callers needs the duplicate test, no-iommu > creates its own iommu_group and therefore cannot have an existing > device. I think patches 1 & 2 would look like below*, with patch 3 > simply moving the change from vfio_group_get() to refcount_inc() into > the equivalent place in vfio_group_find_of_alloc(). Thanks, Yeah, this is nice I just rebased it onto Kevins series and the reason I did this patch has evaporated so let me check it again, maybe we don't need it. Jason