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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?fjNKxVU22UWQZL6W99hweHUrHOv7AniGpsuTKQV2qwioPGd1xl9YayJcwg7r?= =?us-ascii?Q?ybDw1WxyN69kMCG7zZQ71jgR7nvnUdKadW+h24SFM3m0mU4v212IMu6jEixv?= =?us-ascii?Q?DhWsPvpl+HuEC/w05dcSpnX59m2D8exV2JL4SL+UkhELBCg6VHeTquVPy2Sz?= =?us-ascii?Q?OF6+8wwQ5JymZvRN4sFg0W3nn/K3qGgotuZrfL65IXvPDw4GNIMShLCXnNqZ?= =?us-ascii?Q?6DxhYy4+0WUEeL1kN0KsIcTl1hg2G4wgZVbwFDRS4Q4i8/oS+19hZ7sv2Hye?= =?us-ascii?Q?G1IcjNfKkqqs2PXgsLlF0p8+JJGa8J+w8EKzAwiuEqmeSaEitLThDcEmI7LJ?= =?us-ascii?Q?GmXOA+7TkTUgbJG8Ju1pRm7mNF04zfBcrBrQqIzwZxCNj8nuvvlsfYTMW1F1?= =?us-ascii?Q?jjlJne7G9UDgy8sE1VOVRC4b1fQXFB50bUUecOjjT37Gg1d5eCkeHvRxC6DF?= =?us-ascii?Q?taNQuehknsPgbL+Y9LAk2hUuwDz6+y8wKLv/vjeBSbbSNzDKom6Q9ODE+wNE?= =?us-ascii?Q?4qWHxqw3aAQelhs7AUcBY93POmI0gls21Xwe//jKo4xAZl0d+zCYFwTMlxQV?= =?us-ascii?Q?5feYbo0XSEKnAZYWfTheNfDg7v1gyiK0JdjRijxnKvhYTdygjlZ2NCUgf0ro?= =?us-ascii?Q?sNVT/z9alWBAj3k1eYDv15vgJrFHxzXZg080m+lj5Fhwz5+LTBjfCBuV73US?= =?us-ascii?Q?L2dqJaqG6SOWpEURCFgBmmr8pLgAUgRp+wcNso6vSov95GzdM1R3F/kRjXgk?= =?us-ascii?Q?7dNxsUpLlLG24gkaVju+MigNacnixzGBjicfaIPssrN+1FSaICKBS4ngShoG?= =?us-ascii?Q?xLz5DaeUchDiFAQCjE9rj3Klz4HAC/4baORPH4ZpLl+lyqMS7KujNDCQj+lz?= =?us-ascii?Q?G/pot59/1+KnIx8VegKwSpE1PuddZ3wt4Jpb3TPhYIV4Mc+hYmfqQHkZHNYv?= =?us-ascii?Q?lSfxH+pzGOeT+eVeN1JKKH2AcyLmzwFcoEDouTLA5z3k2Jkg3G645xHIA/hJ?= =?us-ascii?Q?MI5ApAIThVSlhVREJkyzma8dMo1JEDw0pozzu2+TsjKes7AgORikAjQnDOi1?= =?us-ascii?Q?MCH9QMqvQNgXi9sonEZQCJU41eK9w/TMqXsc2Asly5XLT/TIZnPmFJ8HkEUx?= =?us-ascii?Q?oHl8dWEUgZJR5DYPqn08B0oeNfR0rkCb4fduVG2xcNzJ9o3wvlyACDcOOZhV?= =?us-ascii?Q?ng5x7J+DWTLjoLkxPokrJ3dy69MiVQvhEolLVbwAR6PnV8HeZPZYG9kLzTyY?= =?us-ascii?Q?s0e1Ppn9uUdI8vp4nzbzEyUg1NlUEiMpKz+I3kzTv+a5JdrAedk2srp3TvbS?= =?us-ascii?Q?HhvjkML1VbIVjY4NeDblsE0V8IgyjY5DepqQVq8X9OPZfr29AzN0PRyh8+Cu?= =?us-ascii?Q?Rb3aSy8mtf2StQn6TBAs5zkrlm+jJ1jJ9YGGZfX3yZIsNoU1jmddQlxGHo2h?= =?us-ascii?Q?HRjKxF0sLkkL3jhXoVikDoG698abw8DgOBrs6h9NHXuTwiuwDeB51wlLWW+T?= =?us-ascii?Q?BX0t5RIGn5PYCAai3o8UFdztWCLMbygQDqTmJGNA2nF2/S0xKLVXKdXwWsmb?= =?us-ascii?Q?vzMURUJ6TG2FDtO5Z8pD5m+UvwLtGeY5X7p4ZJ96?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 847f369f-ef02-4f42-cd20-08de33e5fc06 X-MS-Exchange-CrossTenant-AuthSource: CYYPR12MB8750.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Dec 2025 10:06:40.3646 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: lqJphbpFIrfLjPF/y4Hc+qDVFyu7IV5RacBzDVI3SOU6Kowdx+2QYZ5DG+O4x5UQp4g3a5Yw0K7OTsQRQoM5hQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB7783 On 03.12.25 20:22:17, Alison Schofield wrote: > On Mon, Nov 17, 2025 at 03:58:40PM +0100, Robert Richter wrote: > > On 14.11.25 12:01:29, Alison Schofield wrote: > > > > > Does this work 'as is', no changes required, to support DPA->SPA > > > (used in CXL Events) or SPA->DPA (used in poison by region offset)? > > > > The PRM handler could be used for to-SPA translations, but it might > > not fit well to other users such as profiling, tracing and error > > handling. Those users are executing in a critical path from a > > performance or stability point of view. Performing a firmware call > > could cause problems here. Since the to-DPA translation is missing > > too, a different approach to solve address translation might work > > better, such as examining the region parameters. The kernel's address > > translation library could possibly be extended and used too. That > > needs to be figured out. Also, my main focus for the patches is region > > enablement. > > I see a dpa-to-spa prm routine. I don't know enough about the cost of > using it to say it's not worth using for CXl trace events that want > to report a SPA (from a DPA). > > If we cannot trust what the address translation code will emit in > this case, forcing it to ULLONG_MAX would be safest. I will implement those handlers accordingly. Thanks Alison. -Robert