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Miller" , Geoff Levand , Helge Deller , Ingo Molnar , iommu@lists.linux.dev, "James E.J. Bottomley" , Jason Wang , Juergen Gross , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Madhavan Srinivasan , Matt Turner , Michael Ellerman , "Michael S. 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?b2dRSWhXbxmXtT3sE2RMrQ67aLgQ2V7Flmt2lnt2xlF7nYDGIztwj3pS2uwd?= =?us-ascii?Q?n+IdGapB3O9UIiMQoPMNh6IsKYHCcZJkLY9xQZ2vWY9lFGHenkO2DBhU3N6J?= =?us-ascii?Q?3xKY2m84lRs19NYOk1XwBBEpQa2yslOb7KS2QaWxIRPyROCfzMwHPy69KJKV?= =?us-ascii?Q?BFF9EPR3++FXYmkvwoef2VCwXurc1CD8pRoWG2eGT/xdbHdCleihs+7897rY?= =?us-ascii?Q?UpLlBNjvUmF1eSfo54Cfxg3R6LD8MZWLlDlkBrCAAyukT3BRTsA0SRAGpK3p?= =?us-ascii?Q?Bp59mj6gjHzhuypvp0OrViKhY3n7/MpZUv2bGEu4J+aoQqHFoxJ83ce8pOT8?= =?us-ascii?Q?JcHnmOWlPs46u4tC4S6398hy+Z3WpA7MmjhGPCIpj+CObtQVGR1QhiW8rev5?= =?us-ascii?Q?m2YZzwpmfX26DMmNvVkOtdlYOzvH1AH9XDK0Hq2jTTX5AgyE8mBk5QZtYpmM?= =?us-ascii?Q?R24hixLtHwIoFy7i2Bnk72wUJfw8R+3UN81wnJjKAhBsvd15axwpv0CU1sxn?= =?us-ascii?Q?4zuWndJnlpZ4D9Pamflaj07NFS5mJTvW0RuFUT6eGoBnKk868wBzBsV8WS/Y?= =?us-ascii?Q?HbsK9l45plYcmvB262RVCdY51/glC2AAPyyebxH7j0qMMPZd08G8Mj2bhlYC?= =?us-ascii?Q?MK1JYB+viCh3E2zw4ExjRYn0U7BiINNFlwQDxXcTSG1WPgmTQNkl/8W92JMP?= =?us-ascii?Q?GsqYBPRN0Tk+NMKhDT1oCyB1l7GVV3it1b1zjWKZXNB19+B14A7resFI7n45?= =?us-ascii?Q?UxRno5xPzuUdgKLsrFfJNYyCyWJ4x/hC3IFxGvSBRDRCSR7gs0ubFj1rC+L9?= =?us-ascii?Q?q4kRWkmFD/vu/KhHNtrqULg9R96Y6cUYrBwF+ALXHd5Ju7aXW597It9vVKLW?= =?us-ascii?Q?OmFPn4E6Oclf+B0pmSeiKKCIuDfhsUlAt9AI7E573B6tBCUbdc/6fLr2rdI6?= =?us-ascii?Q?QwXWvOAOyh/x2eWZlycfF4sI3/2EjkEH7PM8stdkClNAQJ7w5UZif9hQQvSI?= =?us-ascii?Q?0aG1xck/nZ8SK0nvxkYGV18SC4MhMO/fx7OSpPbSZU5hJ8dzf42VKpBsW1ko?= =?us-ascii?Q?Hd2DGVH+Id5MV2x3OUFuLteRhvJpnJ5RoHIrXX7AadTB92BSeUwKRxD8vWOo?= =?us-ascii?Q?526CO+pAwdZXiKuf0+p166bkDVVA6pGBDOuBaVMy7Oq254E8I+EmFuUEgkT4?= =?us-ascii?Q?lnYRmakGc7nhByRNoxWPbPQ3903cj3yaZHU/YmrhWMpzU1bxviqqjwbigWvY?= =?us-ascii?Q?o9Lcx0L37MWjqshxuKdEPJXbp3kZp//5QtWhQklEK/ZcHzDNcMkEr945NiDf?= =?us-ascii?Q?wSvi0B0pICipxRbP7Hgf5oSsFnkZ7VAdgEkehZ9Vrny6i7NIpzzZgHUcoPBE?= =?us-ascii?Q?u59mrMT/zcYkE/T4cdL4hSqPdgeVLGJTEySRMF3OFKasyYh6Qzm6sx9PrFBI?= =?us-ascii?Q?snHORk1rGeKHm641Npj5XwUduR6t4sqNUe/YOQpz72qNfvYhkx7OL/ZWUluk?= =?us-ascii?Q?w/Ty1/+exY3HZiGuKEvVjBW0nKqBXCVfAgjunj3M8WsQJw6eQh8AyQt+fRZO?= =?us-ascii?Q?fRx73xbZvrOMSuHqXbk=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 61f9b3a2-7185-4f61-5b16-08de02a1f777 X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Oct 2025 17:26:19.9467 (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: INI0kVWRWJoAj8g5ME8XCvKknEdjhjicXmAR32iWuNcBMkcBLPfGdUOAsp8SrNgq X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB5953 On Fri, Oct 03, 2025 at 01:18:32PM -0400, John David Anglin wrote: > On 2025-10-03 11:01 a.m., Jason Gunthorpe wrote: > > This doesn't actually use the virt at all: > > > > offset = ((unsigned long) addr) & ~IOVP_MASK; > > if((size % L1_CACHE_BYTES) || ((unsigned long)addr % L1_CACHE_BYTES)) > > ccio_io_pdir_entry(pdir_start, KERNEL_SPACE, (unsigned long)addr, hint); > > > > And ccio_io_pdir_entry(): > > pa = lpa(vba); > > > > Is a special instruction that uses virt but AI tells me that special > > LPA instruction is returning phys. Not sure if that is a different > > value than virt_to_phys().. > > ccio_io_pdir_entry currently only supports KERNEL_SPACE. For KERNEL_SPACE, lpa() and > virt_to_phys() are equivalent if page is mapped. lpa() returns 0 if a non-access data > TLB fault occurs (i.e., page isn't mapped). Not sure if that > matters. After unfolding everything the expression is lpa(phys_to_virt(pa)) So if that is always equal to pa then lets just drop it. phys_to_virt() always returns something kernel mapped, and it can't be unmapped. Jason