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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?yePXdVtAqfPtFz6lierpGeDecu+qsLw93UcOw75rBK0Mfd/ZMgbFg7owe2Pp?= =?us-ascii?Q?M4Vqeed2o9XgtyMjS7HMOl178C402nSOshTQsD365DuwY0SfQldHtYPWPF4E?= =?us-ascii?Q?sP0vWuxdj11rzzh2/v2bf4e/Kyh9okUwZpYYhh5x65Y6Mt/jc0cMpPqI7qvJ?= =?us-ascii?Q?Unk8S1eMIDqHnOkaMMXVoPZbG9z9weBQZpEy5T28bfH8UKRzAL3ZUCfM41cq?= =?us-ascii?Q?b334dvL40qGL9AxzbS3AfvCe/RCxb4E2tSwxDA3LG+S18Q+m2DXWU2+6bSGK?= =?us-ascii?Q?FcZeLqP3W4B+rFAANY81vcDhNiuuTOaisfA2zj2Pd3WXNM+GEBHISpyAGe3v?= =?us-ascii?Q?Pb6cHCR7X0I6ek3e4j86nJS+e9ZmNIdrJIrrwf/RL+1JknEDQT7veqZx07Cc?= =?us-ascii?Q?vZoPV9mcftYc6IHlOjnlY3Mt9un7IxTmUWj8erYSyJmWBDqm/32NuKu2bmAs?= =?us-ascii?Q?hEMEJg73xN1P2AaYl0NMZ3/4w+qAzOp7Uy/L5hlj1Bq9I0L4NjkVVzwQejZm?= =?us-ascii?Q?3gdRocagTPQhDxzNhmbffHDdbE6q9UoafNXqqpCPTUUOz0O8AdNXmnV6BCeN?= =?us-ascii?Q?ozKuHnB2CoH5MLtcyR/tJLWrvW6mQCtVWl9JD/9t0XTgN6MQ4QcQurNJwZer?= =?us-ascii?Q?KxYpJHqEq5PmITGLgDluOZq7osoOWOjB/jTzhmbw75BJQ81d+KFTQkgTUnUY?= =?us-ascii?Q?AEqpg/z/zSaT7F2pMT7sdUPAguWaCZaDUtfSPf/GwmbJZxTEHNHjJozVV1xF?= =?us-ascii?Q?eTWqymqzbblH1HgHDTTzGUFb2NI5f3Xs0/r8FEhAxSnXdV809VFcPaf3mTzu?= =?us-ascii?Q?K+fN8KWCp/8ehwY083KbSv5WgAyHl3h5VqQCcUNk3frbkCF8vju3hNVSFwB/?= =?us-ascii?Q?O5Cs99jF52te0UamahlAoX/mhRS9EaTaZWNeptDRqViCggWjbHa5jIQWgEOm?= =?us-ascii?Q?wx87QmVlXSiu0plLKRX20FLX14DaM6E1SCs8UDHvFsaJfl48Css+LGUceLTM?= =?us-ascii?Q?mj8wALUNcK7yfP9iSUvvue7UNXMXoUlLpoR8yVtvY0XkhXZWXVmx9UGHbib5?= =?us-ascii?Q?80DQuz70xCItS0FCwGjgNYM7BRM2eV/WEktwr8+RueLONzI1n1SWFGKZgjjr?= =?us-ascii?Q?FtzkCDm9WTNrVZO1g3OAVYFDWAkkpgv4NiArenHg8PkwhiC4xhoBqFodHs9p?= =?us-ascii?Q?tLw3tjtM14AVgcXTsIiztqiumubrZ44uP8wgEcQG28zcyaTM2XE2Qo+5LtO0?= =?us-ascii?Q?newaOniWCJuvtSNI3g75XQVu+XbXDeTBzs32tWOw2TmVFBOVAO2GlIhmejuA?= =?us-ascii?Q?mRGUfAfwxehkagMm27X/GmB1QE/OHMBzhXjue3278w2u+8QXbL+cAbsC2tKT?= =?us-ascii?Q?2MdMCI6OXtklFi2NjeGpIoaQVy30pmKTS5WWJl17xf6zE2xWcslTBwzb+8CZ?= =?us-ascii?Q?c1b0P2fqvFCogW+s2glrIUe55CzBp8HyYoHDgeG3ReofZqxLDXdf4vToDuLN?= =?us-ascii?Q?jWwBnHROC7Wkm/NSRCvtpIXMlJPovfXrJzag2a81iw4+h9zQvdvTPUyFDiIN?= =?us-ascii?Q?O85c3JQEfDud0dpM3LBPguEIx5dezCONCYTosSyxqonSSHZ23bocSMcjlTfI?= =?us-ascii?Q?j8jHvbKewyGkGSQhK6Mhb1g8QGPI3CO/BRzqeqePi1hV9NUXPBOB8LXC83Ct?= =?us-ascii?Q?yP/8RXhMq+vFPYfRDULs4TBAVOp9PTAgWDsE9uSmrU3NKUcj?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 73c3f93e-3f9d-408a-34d1-08df09c99923 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Sep 2026 14:42:37.8914 (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: b27IHUWkM1IY9q2aQB7YElX9UiKDyZMS77NQjC2TS/vUdWJIarM3COMpQKs8aknZ X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY3PR12MB9702 On Wed, Sep 02, 2026 at 11:19:05AM -0700, Jacob Pan wrote: > If we do want to support this kvm-vfio bridge semantics beyond kvm, > maybe this should be abstracted as a generic VFIO "hypervisor > partition" association, with hypervisor-specific get/put callbacks, > rather than adding an MSHV-only copy of the KVM hook. > +Alex I don't like this patch at all. I think we should try to harmonize all these sort of "external" cases as best we can. mshv, confidential compute, xen, etc all have a very similar shape. I am discussing here with Aneesh an approach to use the viommu almost exclusively for this. https://lore.kernel.org/all/20260902235609.GG2890729@ziepe.ca/ Can you imagine a way to do that for your stuff? In that case I imagine the iommufd vdevice create is what attaches the vfio device to the partition, not a seperate ioctl over in some other driver. When the viommu is created it knows what partition it is affiliated with because it took in a FD that describes that partition. Does mshv use KVM at all? Can a kvm fd describe the partition? Jason