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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?pa3+B+QjNeLrN73pxAsGDxqNaTxADCmnY/OlSSo4U8l7KfsnTVnJCZ8d583M?= =?us-ascii?Q?9JQq1E4bdqaxaFQJue4CTWrTtrgF4V1TZ2AP+14JKScheB96moLuq6AsL9vl?= =?us-ascii?Q?yy0txTMFC/srBTkj9fFd29lX75pgc6B2Ue8kT1Y6pMnO0FEjBGRKDlc/rTpT?= =?us-ascii?Q?a0kY8vLJiJbAOLtSidZb0mUF6ftiyPRmc/jdaDAO6AMqyUF9hLxM4IMI+AWH?= =?us-ascii?Q?f926HBFcya2rJyATD7yYSw4NXlHqW+WVLHX9kTzzLB6q4yBCFes/4eY2gKB9?= =?us-ascii?Q?SqIjAnn39yQPseVlvl5z8WIvWfrIf+LSDXMKUojNYubCpnqN2K/QHmWdA1D+?= =?us-ascii?Q?2oI6gxj4oOugP8aTboRVcVLgm7jqCUgA+GFGekYMx0NN+y51X1bp3XUIlyDT?= =?us-ascii?Q?4BahSXt/k7Iy5/NQAMMVUu4ofO26vt9EDT28gftQEQWd0qVMqtpAz/qiCCvY?= =?us-ascii?Q?YPAhoLxwNMu4BjFL23+dBdd7cx/JWYtLS0jvjt+hx9awUnn/c/hFpF4GX9bx?= =?us-ascii?Q?4YIwcNcHkI5FRssvpdFcZo/t3p32MDJpz9Y4RqxGIUteWVwMoiQd1WhSDSE2?= =?us-ascii?Q?DfNPP3lOS79nK5zOCsWM6Xngh6hE1xMeNc/dqEokneEkI/Jf2DDrXb6CH5Z/?= =?us-ascii?Q?mTI+GFWdGv1T4hcNIkVdTrwS93DWMjmMKwFzqowf0IoRAHAfvOKqomJKkdIS?= =?us-ascii?Q?2PkP3bBUSD4qkBS1tBTJvn5Q/6U3M2e0fJ2x/a5SJHK0cME4fchpJVsikh97?= =?us-ascii?Q?HSsnC86aTi9qsCBDqW548iDBaObaW7rxYWGQDPcr492KuSGtehVMwkaEiOvB?= =?us-ascii?Q?OU6Ka/Yjo4GFBNx90irMq+Yy+ivZ3mnMU4t0a6pO1nJfKpiJ28I58aB2XA42?= =?us-ascii?Q?8srwOdR+0mAyCpZvPqb2VFHRgXW9G7yEqrbbGvflWPpg0tyM1b6UfoVp40in?= =?us-ascii?Q?XzNz5bWMcOsd4Nkk/+XpxxTqA/vb7MlaxcVAJ6hCIV0k47GETQ7yMERI4IPB?= =?us-ascii?Q?kRKfeVvItVP5Q09DNhlYWKY7NEcBCC1CSWv9XCtmmE8cuCoE6oy+GXBow2WR?= =?us-ascii?Q?EhJ+SZL5PdnFztoIJKVZRzGoDFbP6CbqzE301nZc5CXqSNEM7Z4R7+p3xWgZ?= =?us-ascii?Q?1KkQin9cL9bF76bvNl13rKhs5spZDzV9D9Xx2zd5YN6tKznFdSZUTttoF24k?= =?us-ascii?Q?b46sE8pKO7xTHCJH3+IxOW5Z2WKXXUcuepDYrA12USBKl6brTiI0Gc11rVpm?= =?us-ascii?Q?w3+RDDakrhpqjZaYGP+59CGogWLCWdWopON6GxJdDi4m7S7yo25Z8kRSlO/E?= =?us-ascii?Q?NVrjg6BlGtvldNEq8ArH9gQwxPbDO9Fvxw3HICL4ace8y86WCUB5OsHy3wsM?= =?us-ascii?Q?yHn8fY14177kMSs0tYJHqXqT4aHkiokuU5EWVW8SCSZMEgeVX3YOfYs5nXa4?= =?us-ascii?Q?y+xhwA+FcLHEPbEXQv2nsb9g8uj1rKnCuNUgOg/28dFgM4957OunthSUgyFS?= =?us-ascii?Q?mmg3ZR0Zyka8zJCANSoMHYixdHSnBsfwRCVfGfWfFlUHvKQSSmgi+sRqcFtJ?= =?us-ascii?Q?+lH4MLmW3WNTDBg7fPa68LYW8MlwBnEMZZyq43jtVvxkaDFj7TuikI6esws8?= =?us-ascii?Q?3bXnF0Op0wIWR632S91w3x8gXdCZRNEm7CijfPsc6Z5nPykVbFn6SfGlC92h?= =?us-ascii?Q?oMBn+Ub+sIiAlt0TIALx1v9Ebv7ap+1K444bZMvbGysQ9zdi?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: bd5b0d68-528f-43ed-e599-08df02b1a785 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Aug 2026 14:03:35.4655 (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: 5quxompRE9yKFwgKVQ6alWtTwINBbpwKxYRklPVgGiT423NqzJHOSE9T+6LL1OqJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB7783 On Tue, Aug 25, 2026 at 03:24:01PM +0200, Andrew Jones wrote: > The irqdomains remain per-device. The MSI table belongs to the > corresponding S2 IOMMU domain and its configuration is bound to one VM's > IMSIC topology. The current prototype rejects irqbypass from another VM > once the table has an owner. The irqdomain does not sit on top of the > vIOMMUs. A vIOMMU links guest-controlled S1 domains to their S2 parent, > while the per-device irqdomain is the IRQ-side entry point for updating > that parent's MSI table. Doesn't sound like the right design to me. Pretending it is not bound to the S2 just to make it global then blocking multi-VM is not a good place to start from. It needs a design where the guest remap is linked to the viommu so it can be per-vm, somehow. > For the host remapping implemented by this series, each irqdomain is > per-device because it is inserted into the device's IRQ hierarchy and > provides MSI remapping through irq_compose_msi_msg(). And this is an entirely different thing, you don't need a domain just to call irq_compose_msi_msg().. Jason