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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?/HGF4LBqjcYEmPkDeOOYATWJmIHAKtviogPKTQYlGwVr/rr75Mp7DzB4xeS/?= =?us-ascii?Q?fk6MYiVJdhXLCsVjjjm3P3zp7BzvFygW0EezQ1iyAFDUdf24jBxpKCXdlE00?= =?us-ascii?Q?Kr493f/N7Fg2GVc+6O4eJnEnk8vqNK8tGhDXJbtDNSdGch9wQLJbjMcxYsj+?= =?us-ascii?Q?Jat5pMzL5ZGCW7OVf6zCotSIuMP1U4nzI3AV8ZJ1L/KJzCVOg520CerO7lDq?= =?us-ascii?Q?8BqR6nMVy1EZnVizkK/vWV+aXuacg5+WR+zRFK5JJPapoPKcCWbdZoXw1yp6?= =?us-ascii?Q?udfTQxLwSjhZeNGvH0DmsxzXueh4fKWm20fMlmMs40xA3Ewyj5/O5XR7cI0S?= =?us-ascii?Q?s/wSuRJSJ+ekGW5QyWxm3vDHgtlVbgI/qWAnra4ULsDVWFYVeN3Ct8AlfQTJ?= =?us-ascii?Q?tE1KpseLSAPuFyohp7Ct27WdHg6xI1bcSi+tY49XVp8Jp6GhAb3C+QPClSyd?= =?us-ascii?Q?OtL9EhsmF+DIMXUGkpS2xqOzUGaWzIugBAVgto7K6a9L1W3/6fye3Q3lOMFx?= =?us-ascii?Q?BXW3QUoMZaWRH7bJbZ1aAGLz6SMBi3upWjy4wohIlCxP9Ek+TYjuafwcHpzo?= =?us-ascii?Q?sBQVp7jPiQlsot8cn4VEevic66rNgMAndMbDuRcNN42ujntwE8JiG5hrBHBQ?= =?us-ascii?Q?bjdbRb7jZCd1ohNBFQDGI2yWb+sb79QoQx9oj3uLg8SNHSMkZExnqrbDT0Ta?= =?us-ascii?Q?D7kSDq8LB+m1wctXnNwGYsi9LAGUSfjrj8ROAMhl7ed2mT0ObRod1a1mbj6r?= =?us-ascii?Q?rb7w7+o25erp6xqQhs7UFhJ+OFD5zHNG8sj2IWAb1gtRNOi92NLpBAXT24On?= =?us-ascii?Q?MzgBPolTWK0YFtxbb1ACpSd+JXPo3fep9gn03PlKk5TnF9Qk9wFOdg0tLWaK?= =?us-ascii?Q?EuTmmlYDBo/8V+mrDnNOobmxlYr8Z7pGcWyrq3hvCKFPKbG+EJ4P8J/s2KuX?= =?us-ascii?Q?lyoolsoTPr1X2gVGFiduTWFzdpO3rVcFR2MpcaZt2HrDSNm2SA2l/Ji673Ok?= =?us-ascii?Q?BxFSRJ4F33fCGVdUrkxQVhOLlFYrDimfQjURVEARe7dIGo4ksPTUqjdz4xEo?= =?us-ascii?Q?8UxG7GW68965t9i652gqpbYLdOLdm2xxZDGb7oFzdry4pdjRh/iPRaxV4IVi?= =?us-ascii?Q?L2+5Ps9t00v7Hy/x9bxEyulIBXbhKK75FYzGBfsbbtXzprPEf+EoGMR73SAn?= =?us-ascii?Q?kWOfuvZegpnQs2t4pmTnRWUPLM+uhhm/9NtHx37fHxrfy4N6+yN3wocZeukq?= =?us-ascii?Q?LhphzAAHOdmOm/L50mhUwLi9iNKdFlRpqNHghFPm5S8tVsQG5kpDREAQZBUf?= =?us-ascii?Q?9EQ+/pT3H1OAY+DkftXXrMy4tq6cPOr+ndCICm8v4M4IfyMjGI+TMEVL21gm?= =?us-ascii?Q?5NcVMXfgvigRYHbYy0ohwFj6M61bRnp5GpuSqJTI2LQl1Gc2hPaCELuc8jb3?= =?us-ascii?Q?+cHu/QYHALK7gZ8QV38+h8z8etAyYL4o6dN869kQaYCI/qm/ZLa/FbgNAtvK?= =?us-ascii?Q?w5l75Qe7Xknu/a0vt6tKA+h6KAZvQPQQYoat6FvAGtT78ktq0xnPCH6irE8S?= =?us-ascii?Q?8br8xK+yF2g2g5wvhJuGZs78sfmMrJSd/1zJNxOZUBqzUMGvL/EW6autT19r?= =?us-ascii?Q?bwa9VGkCPMLV/ieJbR872Tcl0C7fuhesfvSJI7fb++BPZzZeVCBkma7WTpoI?= =?us-ascii?Q?lDcU2j3F+8FOde+ZwIus9HWrHhkkF5Woyrtj1z8F5MyPuLBa?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d6513d60-4ef0-4932-292d-08dedc83945f X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Jul 2026 23:58:02.2778 (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: fS4R+KaINPSfIAKjn/R7qTvYfYnc+lAgr/Q/XRN4bDRjVvyH/zZJtHl8ofyh3whu X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB8450 On Tue, Jul 07, 2026 at 04:04:31PM -0700, Daniel Mentz wrote: > > > Support is gated behind CONFIG_IOMMU_IO_PGTABLE_CONTIG_HINT, which > > > provides a compile-time opt-out for hardware affected by SMMU errata > > > related to the contiguous bit. > > > > I reviewed the errata and didn't find any related to contig that > > required disabling contig, the driver was OK with the ones I > > found.. Did you find something specific? > > Arm MMU-700 is affected by erratum 3777127 ("Under invalidation in TBU > possible when using contiguous page table entries"). That looks like the same as the one I found 3673557 for Neoverse MMU S3 > However, if we disallow partial unmaps of groups of adjacent > translation table entries, we implicitly apply the workaround > ("Ensure that contiguous page tables are removed using a single > range invalidation. Arm recommends using range invalidations to > remove contiguous entries anyway for performance reasons.") Right, that was my conclusion as well. SMMUs with this errata should not enable BBM level 3 support which is the only thing that can trigger a partial unmap of a contig block. My assumption was RIL is supported in all affected SMMUs since that is the recommended workaround.. Jason