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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Obes76O15kVFupX2NeOYBXoeT6ZCQkW9wwvvccROsG/1h6LjpIoy1U6mA68s?= =?us-ascii?Q?spj+7kv/0XF9i6D1m78FU7pi65K3OXW8Rgb/DH4HBSpDRxm25yV3P7AXYWAs?= =?us-ascii?Q?woZoBKTwaJkqiADOhg5Rwo0IzPPgGfnUvjOdg0tjYOVacCxYezkM2OdvRL5i?= =?us-ascii?Q?o40CwDSFCyYe1o+oDvw6qM5sNUFn980qGoEBRGgyXc2Wg4ZMQpY/tkiFSnDP?= =?us-ascii?Q?PwbilUPG7PS2sxmgIjMJlQmZXvTyHjerVIoFJsFWmuC6V0M2FxzM6P6wz/gV?= =?us-ascii?Q?ot3iECDwTiE3W0RokZ31Bq5Tk86ZsGCXV4SOsnVVyEoTydtOqMuZYuqHreIr?= =?us-ascii?Q?V3+47sPz1mfgNV2yzvxsIJPOTteaCGAzD327fEBxXIOinx9lECGZuayNOpo9?= =?us-ascii?Q?xZExJzDbIpZgTyqAWLwhiq5JRXQeXjahIbHuHDrWXmQn26TELT2PkDBKiMPV?= =?us-ascii?Q?dEGJGzIGRDEiwa3pw+EYKx6m+RknFZA1V5xFUlcYbw5meyLQVTwx5eqDpSPI?= =?us-ascii?Q?rhg9mYRnRbIf+56ZXD/JuZXLM/qkRzH0MqAkVWWKT6DMb6WNA8SeTxKFKhmn?= =?us-ascii?Q?1X3vp5E4JQAiRqc3fjoumouRNc7aHx80xKgy7h5qJMJQC90qANBUEzZ9MHMb?= =?us-ascii?Q?P3KfExv/LGz2zx/hOb2sNEgFbaJ10RdlnBEq3V2MoSBFW5e98MNlEmJsdthz?= =?us-ascii?Q?0oYEnU0G3pTkBIOpbIcSJJ+Ho1559xsm/ypsT91gG4uw5BI6ZCiaGHU047Q2?= =?us-ascii?Q?s4QIffndCaV0Mea51atXbk+1BwGZckSDA8HX5bLDJjAOktB2rLJv9LdIv5uy?= =?us-ascii?Q?JnUK6KcRBPRqGqSH0LHikqZPUAYLfRSeLuvaiYvSueeTpknrUwJ9eF+IaOId?= =?us-ascii?Q?MavH2tnZOQiGJkY4if+mSbhpaqVL8jQISF7SdjyMc9KC4Gi8u4Cn1pykflxx?= =?us-ascii?Q?Y+/ncq+Drk7fRrhi1wTDsWTz0GtudTkeKmNcxSt9KfHWSYyDJJtHXdIKhTCa?= =?us-ascii?Q?gjEau+7+IQQy9WZrV7gf6NvYGzRoDPUAfdv9AufPXh0tPnsz4hiTrTgJnDGP?= =?us-ascii?Q?GcpJfP2br/bJmARV9Ev1uf5S72sMcpXJT3TA1Mpo7aFq9pJ43VB8mCOk2Dqr?= =?us-ascii?Q?yhK2Rs/BD1BnybZbtxmfX0gPfRaofsq5NZkK/z+umVsIdfO3f9FuU0kI709i?= =?us-ascii?Q?5UOMMuhWxVeuYRPZDBnDE4X/rMCTMoPWpwSiCakPQknZGz29mOEg+YeM6mXB?= =?us-ascii?Q?eNn1CJMx3F2VekFwL1Wuv8nXkMCsJfTabEwSU6bAEXLPn9SHjXRJAFLVa1+y?= =?us-ascii?Q?CA5gu8NjX8F6392G0AEktmejiFeuZJCAaP6mfjKwShhmyoZSDXMBHFFhHmRi?= =?us-ascii?Q?uOBj5UOtCYqSGkEZ6u2iVdq9/Apxdrs/UMbMK17dm/VmiRLW5nDHSKU7Y7rl?= =?us-ascii?Q?ufYGm7nbPDvdhCQwLC58hbYpcjUbboBNhqEcWSBKy8jCbjqAAKPvFIqvjzET?= =?us-ascii?Q?nAeJEKts20Nnrk8HcEDG63Aa6qMkIXlV/wNXCYWsvXo13KAB1V2INIITcaGo?= =?us-ascii?Q?9r0dcWlYlyckdhHOlYP9tqURIdFseqbubxMdyLQqBEoFnDEdr8CZoQN1Umr8?= =?us-ascii?Q?cD2BL8H70WuVh+qWI9J0JlXkg/CobUKE0kV0ZJxO0+jW/BI3/RscjCI2xWjm?= =?us-ascii?Q?4g8xA1g+hGlqPTLPlfwuLHAfWz6MBSNMYh+mgVtf2FSac1t3k5lypvEUTegD?= =?us-ascii?Q?PA7M/yQAKw=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 23ef8db3-9100-4098-e87c-08de6fde2382 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Feb 2026 17:41:40.4695 (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: f904I8aPNnLwuCq2WMXGgyGzNcNTMcA9fUkCQ+x1PX29F93MSGcMLxcTQcoYVY3a X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB9470 On Thu, Feb 19, 2026 at 08:53:19AM -0800, Nicolin Chen wrote: > The thing is that those driver_managed_dma callbacks don't call > iommu_device_use_default_domain(). So, the iommu core loses the > trigger to switch domain from BLOCKED/empty-DMA to DMA/IDENTITY. But they don't use DMA API at all so it doesn't matter to them. Your issue is that BLOCKED breaks MSI on ARM. That is fixed by using an empty-DMA API domain as default. What is missing is to bring back the IDENTITY performance optimization in a secure way. Jason