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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?OGt9KK0BZ9r2ndE8cd6PaC3l8X3t8TxblUwAqIhPQVViwSFCdWicPi19O3d0?= =?us-ascii?Q?mhiWtJA3x1S5Q8jGeQEqEj1QGsSefzefmumZKqSbUCdclhE6xpe8YrT5OTou?= =?us-ascii?Q?1w0D4Hu156h3Zlc5bAL11imWASOkJsQpCYtJIUPvhFePeswkTFmLK71+pICD?= =?us-ascii?Q?7KM65h4DlT/sVIGQD1v7ERHtIgx35EZVNaVIlh7wGXZKJUxPsT9HeMOOZEG9?= =?us-ascii?Q?cuyq081aqow/olhhvFZ0K0j/PpZpIumoEscc988/yxVwXPcQFJNKxT8w85kg?= =?us-ascii?Q?NM+gV+UpopDuXk92MUcDzAXQrlL87VQ0YzlVt6HtX7rm/Nl4FI78o3AjVlOT?= =?us-ascii?Q?PLStUtz2FQSxv5GOMuC5+Gl/oOMDX44ktbB8NwT2WvUezW4q6Y0MK91bnnWl?= =?us-ascii?Q?a+r6CJEOLED1R28hs0x3SCNp10NMPOVUYpPYAWXYdDluxqUjCpXrbSaSkEQ6?= =?us-ascii?Q?tdbqn1HQaDrt82pnqwZuJ4rNFGhYkEFnXyTYCqT7XvbtIIrm5jP3RRWrQSqD?= =?us-ascii?Q?pbTdslBayQD56WMs14bRgY8e4mRQv5FZ2J1mEGdYrkLCHhZMOE/tpyf2lgV3?= =?us-ascii?Q?aFXHwF/gKQty0gMOZDV21Ge4rFsVkAj0+OsPZbdwXwRoudiYkKYG5quprnkg?= =?us-ascii?Q?55A2lR7Qjc2Wvx3Ze3/vUJcJ+//mk5AWywYRcop+N6gCiZ0KjAF7HXOq8T6M?= =?us-ascii?Q?gd/hhoDWbzdKvmpr5CP1XPhBxvwJy6J01dVt9I+EOjXmVILrGdb9TWvZ19bv?= =?us-ascii?Q?R//aeg89XrX5RMM2MPp7LWLCxDZX2J6Cq72MUlhVW3Lqvg8oHQr+rL4qE8bt?= =?us-ascii?Q?RFxJMqTXiTr2fAcdoCoyvyCh/L+TDZIgQFQnlfCUY0kacNiZApT8ByowL7dt?= =?us-ascii?Q?7bfGt9Po3iIwCqeIs79DvEJ3csIyD+muH1oiQ0z0rK88e52ab0F5lQW0TXNX?= =?us-ascii?Q?3tkYZtW9km9sZyW6hZ7IAJeDB2B60W0YGW36Ms+g1Zxu2+qUPATnGJo9NWSm?= =?us-ascii?Q?45ETOeieZh0u9bJoQ9yhPhvqRnt0fGJZ97GLXEAtVScfc1eKJ2YTFJK5Ke/1?= =?us-ascii?Q?XIeeO8TyO4gOyOnzxAgt7nKuHQPuA93Kvtq/Lz3cKu7xzw92V5c0p0jA+4IQ?= =?us-ascii?Q?EaxISnTA10C3KujHymKXiK4MiZW33IcaGaX9q7K20p1pB7mau0MXI9sR1g0P?= =?us-ascii?Q?eartFnbO7QE4rXTx2GRA+CLY7Tjnl/5wW5cxMwCbrntYkRfEMMGf2VbecpqF?= =?us-ascii?Q?5okFTUN9jIjthLBXVLV4xoH4muuCeHp8ChHAw218t4om6Zw+Es4+1h+2bTl/?= =?us-ascii?Q?PtGzAcbzwEgztZJcSB93AfXaNelOoQtaWl05W7FXFy7czf9eMOmCCh0GtBNC?= =?us-ascii?Q?8u7nnhtavfELmzjp6yrEoB6oWrF64XCAO9mPNH7vnuFXg/U1IvpKm5PgH8uC?= =?us-ascii?Q?Rg82loKyymA/nmI+xRJAygDp4amQSM6dzkX5OOeI2X+j7egV5nuPKNbzYB13?= =?us-ascii?Q?pZD5P6uRZh2ZBbBDIX4ut0kwaxulFmGfc9KarXmBsz9ffRa17dfry+OE8IaU?= =?us-ascii?Q?pVvQSj0MyVj/zciNyaI=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 59ee45de-9ea3-4d4a-8db1-08de1b0a5a52 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3613.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Nov 2025 18:54:01.3813 (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: GBFFQPVVX6WJAcuBxzILU3DDIplJh+q6ILmgLpN5n59SOQ3VaaYHRADviDm+1mHF X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR12MB6431 On Thu, Oct 30, 2025 at 12:43:59PM -0700, Nicolin Chen wrote: > FWIW, I am thinking of another design based on Jason's remarks: > https://lore.kernel.org/linux-iommu/aQBopHFub8wyQh5C@Asurada-Nvidia/ > > So, instead of core initiating the round trip between the blocking > domain and group->domain, it forwards dev_reset_prepare/done to the > driver where it does a low-level attachment that wouldn't fail: > For SMMUv3, it's an STE update. > For intel_iommu, it seems to be the context table update? Kevin, how bad do you think the UAPI issue is if we ignore it? Jason