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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?qSd7jU19TFgHeOf7Cl4aTLlEQv5HdEcTIYOtdRVbI/eb0FTK3UzLam3PKVR4?= =?us-ascii?Q?xOr6axzrYBK4SBjRbNxfeA06ktGkbVoTFb5hoWboa+TEkjxHcKAwxj/JleZB?= =?us-ascii?Q?zO0RPkDH03lsZY4ObJ2f3zziw5WJGVXQNq/dLEbiSp4DhXA9cbnwgAbS0RwR?= =?us-ascii?Q?vFeUmUtjk2A3/HTi1Suj8vafVw+ycnZGFvzJQpsdDNtoowzh3zpdCOpb+36Z?= =?us-ascii?Q?87ME7uSxkMvNzG+D6InmoO5QVxfwGgEYjorcxG+NTORSUPn91h2LeWZwU065?= =?us-ascii?Q?lZKuMvTL1iBzT5ROjleY35xhb3BHRWI+Bv+bHR1n0wqjPZ0FWeLfrMoQNsn9?= =?us-ascii?Q?A99t8qYLmkLqq0xcvp5Hq6Lqe2fzc/pavXDWPkk1LVJkMaQa0ZXFWRgFz5AN?= =?us-ascii?Q?uXuPhuJCS7Xza+jMGXek3s5Q5JMS/pJ9R1foa1Fgi4kFTRpQGGRQJMeoQOtC?= =?us-ascii?Q?h86tVnBdlvfM3Ng7/b0miFq0Cu95Aq7z+UrozSheL0Rb08Ot/0E2GmVqZPYl?= =?us-ascii?Q?9n6Vw5wjSKXeSPABHprmPpSDYUulW8Ue54yG3rY5Vjm+wEfMD5VTUZqXph4N?= =?us-ascii?Q?aCDaa79Jm7OIgPDnAEn9po/TfNqR1A5RzqqjFgaiVSYMWxp81ftTvkBy/Pzu?= =?us-ascii?Q?w7qic3on/frzb0NGYXdfUoyiDUYc06n0jU9zJfZhLjiZEjltCD6s4FvNExXn?= =?us-ascii?Q?qmz/DdnZjyG5JUEuorxNorpB4o2CxJMsbqe7E0tGTJL5UJZIatfOgfDF/V0T?= =?us-ascii?Q?Mqc38TIHT7WpKfxQvNxoRwS3Mxz3af0mTxK1j0ORW/z4nxHibq5i5kqu4Jia?= =?us-ascii?Q?oPZnDtdBmGfsZXX4mz+Xp6SENJuRaThqPZivly4HTSIendH8IYhvKm3zGKkH?= =?us-ascii?Q?UeW9IeoMtq3JhXngF4QYo24mBtYLMeQxSfXx4ZzxcmErZPuefAxTHtYce8T3?= =?us-ascii?Q?FvmaKADi83xFuGuNHONjwcUfRe5UCc17Jd6iNDZePzgp6ElnD9TuiOed55mM?= =?us-ascii?Q?zGxLHmXn4GSLaxwVgaOb1mW6aiUmWskmWUzD10TzOPGLhXTx3Ay2sPFxAisc?= =?us-ascii?Q?EDZLW2EFuV1Iifof7MIVgrt5bNqFNicloLqq8g1CcWd3dpO3Zre378a87R+d?= =?us-ascii?Q?3Wd8lvbmavOvm764QbGuSP/L9jujPdj0L6dFwZdqMDiWl0jVsK6nBTQ1nZS2?= =?us-ascii?Q?WF164r/cDA/09FVrWjC5M5dXR/lT6Kg6HTIzQNEyXpYnw8TboNDWupakWJ33?= =?us-ascii?Q?fm8m1/YY0L65oTmoocf1gfg8pf8tMDLyErthClp8h/0PxFSdJIIF2Jw4uJhW?= =?us-ascii?Q?7NbDprG/4MZ1Hnua7KI69wtYcUSoeAds1/hi2Lr47HiikRYc4KyPrtsghILV?= =?us-ascii?Q?HHcd1fUn21gTkyyr54Y8Qe7CVN/tdET3hEi7y355cAOBhVO+Vj4DAOppIPn6?= =?us-ascii?Q?mQ6CPO0YksXE1fiIFZc/p8ab5i0YEuODSMlhIwZA1a8enNGC4VDxGY6SN0BE?= =?us-ascii?Q?4h6JH/Ib4KBxs/JHHNqOISn2eiupkC3P42s6NRguWwWL5qPzKhex2ihcgZai?= =?us-ascii?Q?C2f+oeIa/lv6FlQKf45X5PzrDSQ30RHiPD0rGSkE6nhFDwkhAUX3lKCs/xMW?= =?us-ascii?Q?89uI6rr21vYJc6hD2YHUkOHgz81UO0b3Sc8FM0J3TSfsPKSz7WCzPK/jlmel?= =?us-ascii?Q?LgclrFyEWJNSmtcszOBJ5MiSQS971nDvfmca/ZexagdqK5J6?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2f10067c-1736-42a4-0df4-08df1e81972a X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Sep 2026 23:30:04.6526 (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: KIddElH7eonM10AtNnYXuOPZPfHFaGcTdEIb+52nuf4iWhTB9BdVKaAs8SzLmo0b X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7812 On Tue, Sep 29, 2026 at 04:15:27PM -0700, Jacob Pan wrote: > Hi Jason, > > On Tue, 29 Sep 2026 09:30:48 -0300 > Jason Gunthorpe wrote: > > > On Mon, Sep 28, 2026 at 10:55:24PM -0700, Jacob Pan wrote: > > > > > Also, we don't have a T=0 to T=1 transition, our intended external > > > attach can be transitioned from a blocked domain, not from a paging > > > domain to external. > > > > You kind of do, external is close to T=1.. > > > > > > I think you are going to have module dependency issues trying to > > > > get the mshv driver's info into the iommu driver, adding a "TSM" > > > > like driver would resolve that. ie mshv could just provide the > > > > viommu. > > > I introduced a similar registration interface in hv-common to solve > > > the module dep issue. Will look into if I can leverage the vIOMMU > > > helper here. > > > > That doesn't sound so nice.. > > > > If we have to have registrations it is better to have the viommu > > registration that Aneesh drafted than several schemes inside specific > > drivers.. > Agreed. Now that the commonality with the TSM provider path is clear, I > will adapt the MSHV support to use the generic vIOMMU provider > registration. Ah, I so I suggested he remove it as it was just for TSM.. We'd have to ask it to come back I still prefer the way TSM is shaping up because it solves all these locking and matching issues nicely. I think you would have the same general locking problems with a provider (regardless where you put it) too.. Are you sure it can't be a TSM? Jason