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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?qX3zipOg9oZ1p2rupVAoiWGV0V15u/9AIQ8tsNnA2q6oIFLL+XrJJ1keEyoq?= =?us-ascii?Q?mSnmIE0Vn5FaXpN/7Mg362x2m9A7aWP2expgnFIO3yr2yBDB5dupY6xuF0Qu?= =?us-ascii?Q?bPm8C+Y+mgVyiQuPd4GZlJ/P7cDm6DEpZS6whILpb0gOIYlQ0+ekCP2Dq17P?= =?us-ascii?Q?fMnE9YwgcUjjFExj3ZL5UTfcJGcwNQaR6/aADtU0gT2Kexo8BegNSB54b8PT?= =?us-ascii?Q?y9kbgV5hjclB+O95w4HuddVTVOqd+zGuFj0aIdIPeeYhrwIQsYp3SBfU5Ks5?= =?us-ascii?Q?6IVbCt/QsopEoJ784blPpRNJDAvOejHE7E4fskR8k6Rxxl5XpMLFU76Q6pmk?= =?us-ascii?Q?7JmQRh9jZOrC6WYJ8ExJGywRUMKkH+sMnANYKUGACUEpKt5Y1n1c3LOaJYzG?= =?us-ascii?Q?vUR7rC/m5p2cghbWtuji8EU5JejRyvaOUVblEOGXTOw1JUkMpFw869KYwTJD?= =?us-ascii?Q?qbuJ6gB6y0W+97mxovm19j0Jq6fEt1rk7t/mULJy5azF4n91g5RBqMxMY6GB?= =?us-ascii?Q?h83WHqcPd/s3LK+n5hupU6q9Ike69vMOtFhrcpsr51JHCciBIB1ktmCrkONB?= =?us-ascii?Q?2EaFV68p2gsbNrSAYyQE86jslVK97r7NDRgZEVGZWuIDxOZFEc5EIe28YlLp?= =?us-ascii?Q?18U3kjbahB7gzEDcfonSUcb8i8EowvRhBTUkI6mhHYNFkfxb0OP/vJsU4gkh?= =?us-ascii?Q?HIVlR5d/CCWL0d29fYx+7TumJYhSlygOiEw2xZAPBDHYCVbCpiPj2JxdOSlr?= =?us-ascii?Q?td1Zx/ReteNa2CS6jb4nzfzQ6rdtcRZdtdyF3GrhLE4D3qzG92p53iJSYwat?= =?us-ascii?Q?BBwzg+9E/Fc3Abm6c/gWOpYsf+ZIiK8GoSz6/lbu6dtZpSkAkQW3u8WDSwl0?= =?us-ascii?Q?WHwQgIsSL8hRfQWu6fgQoGxbuhhGJDuEFIppqCb5Lhy2NWLw2PEPC8RvT6jX?= =?us-ascii?Q?SFg6duQvZ9OFmpWVR1zniInwHfdmX/4/5B7gIOiuzmES2AI2UO1USKMO2Vz0?= =?us-ascii?Q?Z5nt88z7exZIYa5va6vAEsMRxdQvbCIemftc2hWl42Ftcks1e5cwUENoBUfv?= =?us-ascii?Q?R3uCVNc5Casuk+k4Gr2Nv+kyAqjA7ZIu1qDs+KvEmm/OfWdia/ipM4moWBbm?= =?us-ascii?Q?Caz6SJtFqGetaLIT8jUGFRn+xPToKZx1oUl5eXBlsy2WGi9io3N/MtJRViWL?= =?us-ascii?Q?0drfB5RJ9eFHDPqDheJMSh3qYlI+96hsC9xVXA0zW64KSi+A8Jztq2piyEz1?= =?us-ascii?Q?31GYc18jukhRFKYyjsbEBCl87AxoH39keQJh7GylrkRG3ciz9lP1XmRhh6o8?= =?us-ascii?Q?8f+b1R4agE22dDmc5oZSV/vtJXnMa9h2kCkeRg+T+Av6Aec1KHKZhjur9r76?= =?us-ascii?Q?+KkPsSPYV8x85/+Q1CFDwLtNt7rCQju6hNo5DL9JakpFccp3cApDOhD8DRXe?= =?us-ascii?Q?Y0Qm09y3TkYoOGBji0cxf/ZoyoO0+pTMif3QAJzS+4XFY/G0i15MsJlfy3Aq?= =?us-ascii?Q?7XKNL8s7yKuyOoiM1SR/J8lxL1qnHtGr5KN4EtZIKteubH3/pJqSLiw9P6nC?= =?us-ascii?Q?v5TRyKwrVNJ60gJaEwjfkhtCdWnvmLkxPrfuX59mU3+Fq0GoevkAscV2itfc?= =?us-ascii?Q?rmN07Bhv71MFiHphjc0k49EKUSKoSyFuLTxOEk4r3zYthI/AvjCow6SpmeSi?= =?us-ascii?Q?Q2+IUfQC01p4gE9bY6Ja0uu8C2E0UJikEMSV12hze4/xVe4A?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cbdaa356-0718-4aff-abd4-08dee265b202 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jul 2026 11:39:14.1144 (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: PvgbelmPUjP9jIOD6xUFFq5xnWYP7FKWNVptyeDJDqecNychgey2N3IHgU2a6c5h X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB9491 On Wed, Jul 15, 2026 at 11:25:42AM +0530, Vijayanand Jitta wrote: > On 7/3/2026 9:42 PM, Jason Gunthorpe wrote: > > On Thu, Jun 18, 2026 at 02:32:09PM +0530, Vijayanand Jitta wrote: > >> From: Prakash Gupta > >> > >> Add support for the contiguous hint (CONT) bit in ARM LPAE page tables. > >> When a set of consecutive PTEs map a naturally-aligned contiguous block > >> of memory, the CONT bit can be set on all entries in the group to allow > >> the hardware to combine them into a single TLB entry, improving TLB > >> utilization. > >> > >> The contiguous hint sizes per granule are: > >> > >> Page Size | CONT PTE | PMD | CONT PMD > >> ----------+----------+-------+--------- > >> 4K | 64K | 2M | 32M > >> 16K | 2M | 32M | 1G > >> 64K | 2M | 512M | 16G > > > > My series to convert smmuv3 to the iommupt takes care of this and > > supports all the orders too. I'd rather we move forward with that then > > try to patch up this. > > Thanks for details, I have gone through your series. As this patch > targets io-pgtable-arm.c directly and would benefit all its users (SMMUv2, > Apple DART, etc.), not just SMMUv3. I think there will still be value in > this patch for the other users. If other users care they should also be converted to iommupt, there are many benefits to this besides just cont support. Jason