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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?lR3NKY/iwN7rbTMn23Ax6uNuG2ixgF+ssNIkJcPS/hxXW3aTuLQ5LMj5Uas0?= =?us-ascii?Q?Dzis766/nmA6vDp3luTmPgshUSsumFw3uhRHJsI78j6w5XLi3HV/YNjOqdWm?= =?us-ascii?Q?Mi6NmTrNCn253fVD7ajqz+IhpnBI4/j7l5KS2gjgX3MAJF4fAXE6GBlfhKBp?= =?us-ascii?Q?woM61eHu1wbyCFbdixi7N+l+EQhmE/3ncVwFKM4kYQIihDMOXHK8E7GAbajU?= =?us-ascii?Q?SccDi8djjUJ/52aBdy3X2qpglvhJ65zEgKjVWJ4oT8w51haazZL7RJwLnY3K?= =?us-ascii?Q?MuGMzDZUj9snQBdmy9DYMuaSI9NNtnRcZ09KpdJ7HCPte9XwzIAW/IR04v0L?= =?us-ascii?Q?Og2URuVaNgotRQ066lHujwmMBDrxFDsHLFVPsYx4jGr0EGams7IFyaUbp5AW?= =?us-ascii?Q?jpsfq37M3rdOAiuQhnXZcnAYHQIFIt6luxYdWv8i956wkGa/JDq1mNFlwf4a?= =?us-ascii?Q?xB2qWzso7PjBbChOJvG3/ZjHZsECztbecAiDWIWXsdtayB6SSaLN32leblQI?= =?us-ascii?Q?/UUV595rJjZdDfgz9SzuNvxhHrJoWr/ZmOP/fY1oNv6vl2xs2KUhI6nkcLlY?= =?us-ascii?Q?ZoxrtZgDw2KCiwBpB92ll7kvDb13KW3CuKOXtOn+G2ZQsrYJUwK7Ka8Ncs0G?= =?us-ascii?Q?Ec3hfA9s13QXMIm8GnaaaMX6S037WFyF5/qLBgo+1zCcwl1kiY0WzH/Rzqo1?= =?us-ascii?Q?ojOL0Kv4XZgN0eUHPZ6qq8CBAKn6ciLXdD/vaoKMiHHGe1cdkdqBH0cPhm8h?= =?us-ascii?Q?p9Y29/Djd/NgEkMZD29hbKT6Hf/Fe+cigWvC9Mv+UD4+Byeoinmy717JddZk?= =?us-ascii?Q?j0TSuBxtEnx8KtQd3b36gfkdK/kuYCw7YcmSmdlnLHnkSmZRetpGba3s4BBx?= =?us-ascii?Q?jnRsJnZz8iEPgKtXWosdQrTcVwwXXPfpwhn1uE+iiz4KQxH1aLSakluyhsNi?= =?us-ascii?Q?wb2YgDTV+YjyuK3JxP51zGZP88leXyHt/DioROQIKGGXXlszCvVEDBjw8ToJ?= =?us-ascii?Q?alJsPXXIbz7cgxDr9wIpAYD0o0DfuezwqY4oNV3MtGlHnOUoPQtjMy6oIqrI?= =?us-ascii?Q?eKAkLEiBwTJaBY+TgrCXNSLZ/YLNfE1TCcPRm9VM6my1RYxMUlgFl84ItSuN?= =?us-ascii?Q?TNpsrgB2noZ8cd1myYmjL1fbNH6p1ueOt4DOg79Sq4u2ig5P3Hm/Tw5nrYyc?= =?us-ascii?Q?sNqFalNzA31898Wjl0lMFKQP7GpLQ4c484JxfPaMHXRrLdcOR5f7Pd+n20kV?= =?us-ascii?Q?mclEtOknjmlKavCtobAzFkqEbaAhEby0JGmUvNLFQvyTNkgW43I9qfpc3oi/?= =?us-ascii?Q?gk2CzqJVm4S5000C5oVi80i54wYgPddMZOKTLHwhlamIFui/A5E7y32PMY4l?= =?us-ascii?Q?SXsZ388zZrDSRDR/ueabEvMgM/a6jYfXsyb3a+q2Ah76Ty2lmI7k7bg2Q5dz?= =?us-ascii?Q?3yarU/mhir8LEaayRmjmA0vaI33A/nQdJTGHF4OV0rafGUfulc2STNfBN/ba?= =?us-ascii?Q?hsKVp6kNcH7/bsSnzKVhGLqvCoKGBYicyF62vybqqHZOpGfoc8cGT9wlWN85?= =?us-ascii?Q?AXpn8O26S8ZpgfadF2mQQc/Ytdpe8kPxzwKUiKGjISiRGC+7ixwBpFqB8U9d?= =?us-ascii?Q?jM8TxEu51aT7LAY9bd+sK50j1mhVZmBgeT8mMQ8AI9KUlmjLuQYLza0QMtZa?= =?us-ascii?Q?NioQtCP8M2Bgw/jVUIMOP3dVsQZJplGx8AHRipeIxcVJ8q9E?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9ca7d5e8-f743-4c95-8a64-08dee29c8194 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jul 2026 18:11:35.2087 (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: ytHFRNCsE6cgP+8/CFQJiwqbUOoesk412GusPXYh4HQ5Sv62b3ixueghNOjbejtV X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB9099 On Tue, Jul 14, 2026 at 09:03:01PM +0000, Aaron Lewis wrote: > Both the Type1 IOMMU and IOMMUFD can be guilty of not playing nice with > the scheduler during DMA unmapping on large regions (e.g., 256GB). Add > rate-limited calls to cond_resched() to ensure this doesn't happen. > > This series was tested using the selftest proposed here: > - https://lore.kernel.org/kvm/20260701203311.326798-1-aaronlewis@google.com/ > > And profiled using the bpftrace tooling proposed here: > - https://lore.kernel.org/kvm/20260630141152.3757722-2-aaronlewis@google.com/ Given this is the same issue on both in the some place, I wonder if it is better to try to get this series done: https://lore.kernel.org/linux-iommu/20260603151804.1963871-1-guanghuifeng@linux.alibaba.com/ And put the cond sched inside the iova_to_phys_length() ? It would be fine to do things in steps, like add the iova_to_phys_length() that just does the loops iommufd and vfio have today with the additional cond sched inside which isn't such a big task. Jason