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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?/ynhBRAMG7Vg9X5b2D/FyBf9qliAWkR4MQZTqqj5OIhv3CD4P90FGwe2u8cA?= =?us-ascii?Q?KvZhasqdTBUZbWqLCDuAO6W4I2rPhBFM3EfcqXGUOBinJAkyp1siQML28fBs?= =?us-ascii?Q?rMf7znomHjMn9te8VToG8wKFFCvNswPrbtAiJJzFPfudvEbXzD7DWippkxBh?= =?us-ascii?Q?TkvsYyd18v2Kti00YzG/35wvAq6gDsW6e7zfib82Y4din9ecNJlw4iPcJyj5?= =?us-ascii?Q?wvZxHDTlW6ynHYB6CoN6v6iSrDFdgHJ/GZVvzzf7oaNy/BDf01BiptoRzrY0?= =?us-ascii?Q?lqQipSlq1pUxY3C3g6+jK2EF2WsZ11vcz2H/4V3rTlIuu9bJCgRQ9EYtA90x?= =?us-ascii?Q?wFWmqfo3tgxjVKa1RIN3wljUqd1QUtDKJTG+nYr1e5/zQ2wME5vg93cXGJmX?= =?us-ascii?Q?sQEpTxoYP7FjR5uxv7UhNtv2QC8/LP5v8He2zTJmZLpK07SAZG+LmEwHJhah?= =?us-ascii?Q?/oubRDjc82EmOrhkSl38DRLkftPhGeo4/eBIX3ILe3rrtkN59vn4JuGPzTGw?= =?us-ascii?Q?WIHUPjx2hjJHZkuNLHUl2fFIir6FTopYhgWCmgIFuXSHDJ3J3pyDO+wXRV7B?= =?us-ascii?Q?SEw0cLRxjobFf/tNXkMvNOdPHbqugjYAywJXywkfPFA6pzfKzZmEYCGVnCDP?= =?us-ascii?Q?bNygw2ZHEIys0y/3cgiazIFi3g/Sttrr1oZMOGbECM0EaFDgtTssHrpa36hs?= =?us-ascii?Q?RVygoOXspiRFn+QEZ8wM/L9pJqzvt/RL84AEwqUhzVdvagjEvIU5LLZdasXE?= =?us-ascii?Q?7JRpVmBGfLcxyNGz/UOsavahuqNBslkfwYXFYGtmRZ6fa5CzdYvBv6syNTqn?= =?us-ascii?Q?c5mfoBBd7wNfjaCNotqje5+cmegd9EpJFs4hvBuOeNC4DR8Z3h7rZ/cLlE9f?= =?us-ascii?Q?jXDsPsvNayzD6gNS1bZdixO9iwF37YC+ESZe6pTrraciYhUSX9AZ9mIezueW?= =?us-ascii?Q?hF7twPUhq891a0zx2e/jomY983Awp44sMPnoypWG1h7wViUC1LF+LD53aolq?= =?us-ascii?Q?tEbse1erqRACR17A4Z0uw7BNatQ4B77dcXlPvvatjOd2n7m6x4JOZ5HIWZwO?= =?us-ascii?Q?f/TZaCrg7C6An6iRn6jeAikUYBQM19yFnZHMMUOXHehzF9kOA7RSCmSNAl6I?= =?us-ascii?Q?61b3/P47HbxoPWsMgw2RQA5G00bMdavv/G3kZLqmKJGApnu5xOtKDqmCaaXP?= =?us-ascii?Q?+nZPSh/1iOjfrrIW4Dowi5om92kByc4sXiJ34hLda/7Bw9MUNHukxO4AqKOH?= =?us-ascii?Q?SgWeeGPvfchggi+v4gnscTom4BWrnMBILwJYKN7PM+2s6T78mxO2ZPg2peVg?= =?us-ascii?Q?4rJkq+iOSmnR++Hld4xl9Z5SEa76laxcBH3+Dg8ztLJQ+tYorxSr6evjMfPb?= =?us-ascii?Q?7lWHU37T9295epsZ3mCmO8BZclK/jkElUtz4CwLQLJjiv+0ZKP8vjavAnCgd?= =?us-ascii?Q?QFhBRc8KvWBwBCMxWCdIEiX8Ul2w/m3dGYX8kGoXS7HDQVqg0DNS4tKUZ73v?= =?us-ascii?Q?d3LXRUU7fYjuXkBW6F0+30j0Ee6bJadEwOd8r7x5mxrj6HgblPzEYz4tLY3e?= =?us-ascii?Q?kP1x7vvhdtCVnfSNivk=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 26215ad4-3dab-4da5-af66-08de26025a53 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3613.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Nov 2025 17:54:28.2756 (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: YNivGgbQR9ynTpLqm9nHUktPNIHGBcVJv6U4xBs0nSNYqiuRpRi2Gm1l4xdU7/W2 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB7878 On Thu, Nov 13, 2025 at 01:52:02PM -0800, Nicolin Chen wrote: > On Wed, Nov 12, 2025 at 06:24:52PM +0000, Suravee Suthikulpanit wrote: > > Note: This series is rebased on top of: > > * Git repo: git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux.git > > Branch: next > > Commit: 91920a9d87f5 ("Merge branches 'arm/smmu/updates', 'arm/smmu/bindings', > > 'mediatek', 'nvidia/tegra', 'amd/amd-vi' and 'core' > > into next") > > * [PATCH v5] iommu/amd: Add support for hw_info for iommu capability query > > https://lore.kernel.org/linux-iommu/20250926141901.511313-1-suravee.suthikulpanit@amd.com/T/#u > > Nit: this patch doesn't apply cleanly on 91920a9d87f5 :-/ > > > drivers/iommu/amd/Makefile | 2 +- > > drivers/iommu/amd/amd_iommu.h | 36 ++++ > > drivers/iommu/amd/amd_iommu_types.h | 48 +++++- > > drivers/iommu/amd/init.c | 8 + > > drivers/iommu/amd/iommu.c | 221 +++++++++++++++--------- > > drivers/iommu/amd/iommufd.c | 50 ++++++ > > drivers/iommu/amd/iommufd.h | 5 + > > drivers/iommu/amd/nested.c | 259 ++++++++++++++++++++++++++++ > > include/uapi/linux/iommufd.h | 11 ++ > > So, this seems to be a preparatory series for AMD vIOMMU, yet it > doesn't properly work since it's missing IOMMUFD_VIOMMU_TYPE_AMD > and the invalidation component (HW_QUEUE). > > However, the series does declare IOMMU_HWPT_DATA_AMD_GUEST in the > uAPI header. I am afraid that might confuse user who might think > AMD now supports virtualization using the HWPT-based mode, like > Intel VT-d. > > So, maybe we should either: > - leave a note at IOMMU_HWPT_DATA_AMD_GUEST to declare it is > incomplete yet, and remove later > - keep IOMMU_HWPT_DATA_AMD_GUEST in an AMD driver header, and > move to the uAPI header later > > Jason? Yeah, I like to see this incremental work, but Alex recently raised that we should be a bit more careful about how userspace perceives these partially complete things. I don't think tricks with head files work well, I think what you'd want to do is leave some critical system call disabled until all the work is finished so the VMM never has to see a half working implementation? The patch to get the info would have been a nice choice for this purpose.. Jason