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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?WRDT+GT9I9wqPyLHW5l15hQnevtThyl4kb5jcbZuLMdsjyklYsWgrHTS0RH9?= =?us-ascii?Q?JRjC1Z2l7qxU3qyiSxogm0zgkFzFge7o4xaFZi9EsxrV5zugs+wndECF+FnY?= =?us-ascii?Q?vAhwyorZVGMT6TqljW+qVXeXIV6ziuBcTL3DHo9SuiVyk0kFknJFg9AIOqL/?= =?us-ascii?Q?4A9az416rI/7rGjAfvVmwFLxUQYgztUbYGX2VTMswd/Y5WlTs66dRIcbQcMw?= =?us-ascii?Q?nf7KALA1Q2lNF5nO88WQ9Kg23TZhDmclpj8Q9zKRiioE8/OZdnEnU6QPbnSi?= =?us-ascii?Q?V5xBmQRi8eMp2kvHfrc8iJgKrXby5q/IKIe2T6FvZo9kLNLh31CCMDTgPIOr?= =?us-ascii?Q?zT8WQQHOuLo4XGqMsB1zuKscxoYBhmGhKc1bqr9sLsfDd1Ld0PE/dDWSeggV?= =?us-ascii?Q?05jDjl+ycgsjw6rvj9E65qqHAvfZ3JxIjY0DpLyx4qXsg77BJAp5z9/2GSKq?= =?us-ascii?Q?TUQ1dX8OVDqxsn2/4IdWYioMq08WOu4Z86MWNEEaDr22qS1F+yXdK4y6qbJd?= =?us-ascii?Q?auaIjEV/cUUXinnB0rgU/45vWBqrGRSK72ven8L0vu65oGZNQIBbVd5xZtpP?= =?us-ascii?Q?XBNsg/CICBpos2jh2tlvwNOrLEdt4YyF9GKIhT/Si+p4qpTeStRCu2scsd3a?= =?us-ascii?Q?IdGLzsWu8ZjpfxI6jmVwMmBARNCwMxZ1gtVBUnHYPeg6w4ptc8I4F3e79Izg?= =?us-ascii?Q?5lXjC9ZO2nUf2egFSXh97KbHMbDj+nzkF7/pVUrrdzm6Wa5en74AVSIIQ+Gn?= =?us-ascii?Q?4OMbnbIHslbyQRaEXdmi6FGyvJUW8WxuzgusO9+5fbgBa7xbFxKyjEjcyz49?= =?us-ascii?Q?RvONLPr9nomiIlx6lf9u91z5kUVNHPBrqpsaOnY/DcqwBaFfyEs4pMyB9Iep?= =?us-ascii?Q?gh2s5Ae+9QT3ynH6KyYg26XV+kmtMKjtMp4px1x/qTD51U3sS79pbOXYrW6D?= =?us-ascii?Q?gEptt2qrhVrJO82wGPP8zFPrt1P3aHCk/hrkO/DRuq4BAAtoLkG/5xkcTDz1?= =?us-ascii?Q?lvfwE9B2k46JnXcjZj3eUmEcYsvM7g/Uk6V4SI/Bak+i6s1k3QrB5U9Af8TF?= =?us-ascii?Q?Ka2pNMfAq0pnrLzQbg/GKWqE1tNXpCU+a93ZabFRQIwTfIih5eWGaBmk0xt0?= =?us-ascii?Q?Yntish9uCAvk6ToNhTeS460MF3WPpJYfxcDYMcQvPDd2UWJsi3Eglf1XGo3a?= =?us-ascii?Q?wMLZ3ei4epHlpboUbJOyuoLDpFdKbDmuKPjIRAmbwNGQmRLBv0yimsEXurIH?= =?us-ascii?Q?QKQhBhyLiVU0+es+5cOP2SyHIvM4jZQ5Q1i7HOegw/qUPC78FMqs4Smo+5lU?= =?us-ascii?Q?PVdxOLJunkOb2sp5D4zylLyeE0sv5NZeN1ZCfESGoWj4CVBwV99sC/aTpbgq?= =?us-ascii?Q?3Md1gPzkNX02dv6nKRFZT5qrN4prUIyou0w+Ehvy6csJlBKZ+MnKVqXy2st4?= =?us-ascii?Q?Iqzdnr1V3MkaQsCSAWUI2XLCRgVM21XUYM977H4kXAj5nZuPVZRnMwerwBmM?= =?us-ascii?Q?Q4N6Eh9x3LUy8FvyUumD7JB1ta0guLCEmGw1rnazZpOwXJP31afkoqCFMDZy?= =?us-ascii?Q?CsLJygabz9PaWPWRiFiati7y5jVr0ULIhb3qFNE9XnTS8PhVWNDlDoEYmbQN?= =?us-ascii?Q?JCdFXijKSCX2TDxP6dlzJ5o/rFg+bBNPmXQRMcj9OUK/pUmlAitlD+XVUqct?= =?us-ascii?Q?kKf0I4jUzu5sQV01GGH45EfsVAgKyKN38Ao2A533DAPEHRFQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6b0b436e-6d78-4f6e-02c8-08debce2fbd9 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 May 2026 18:00:20.8697 (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: S6NP7IzHfC2U+As7ZnHG11aEtmW5LJc1OuZpGhN6qo0/k8UBZifjXIvyY0l7EKY9 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB7089 On Thu, May 28, 2026 at 04:32:23PM +0000, Pranjal Shrivastava wrote: > On Thu, May 28, 2026 at 12:29:30PM -0300, Jason Gunthorpe wrote: > > On Thu, May 28, 2026 at 03:24:40PM +0000, Pranjal Shrivastava wrote: > > > > > > + master->ats_always_on = true; > > > > + > > > > + return arm_smmu_alloc_cd_tables(master); > > > > > > Nit: I'm not sure if I'm getting this right, are we saying we *need* to > > > allocate CDs for CXL.cache cases in the probe itself because STE.EATS > > > requires Config=Translate with S1DSS in bypass? > > > > Yeah, basically. > > > > Effectively the ARM rules for enabling ATS and Bypass together require > > a valid CD table pointer. > > Ack. But do we expect transactions before attach_dev? What'd happen if > we don't allocate CDs here? It can be done at any point before a non-abort STE is formed. The core code pretty much does this immediately after probe so there isn't much point in moving it later. > Am I missing the fact that CXL hardware could be already active and > using ATS after the device_probe succeeds? The STEs are preloaded with abort when the driver starts, so that should not be possible. Jason