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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?LOFPH3gCiOeAsctuZzDXVrex+940zU2SnOC63YpxpnEVZT2+gGE+6hYO32xF?= =?us-ascii?Q?gdMuSsKAACdKL/8wacLIM/NZ6/Gnm5hLQbuqdiUt42FvN5mUEoW7QX9zSSQj?= =?us-ascii?Q?xCQvRjSZYsxcNqxyI/D/TrLOXO7BWbmVJVEFoR/vE4aPlbPN19ONbXBwEM+6?= =?us-ascii?Q?ZgpWaH4HEc2BQn1UFnnNpn1wIahVeZCTmcUV+PRLaiMFUdNQcIIrLUGdTquZ?= =?us-ascii?Q?cogEXVifEqZ0/74THY8rIfjXupqX2QmcA1eYbRkl9f0KkEt89feIdz7Io+ZQ?= =?us-ascii?Q?kBhYKru9bg1npWgmCE4aDAYw1N+28XlQt9POxl1mKBEcS1a9mY8uA3IYgx7p?= =?us-ascii?Q?vw/0Ay8cp2sxT9GIaQZYfM1vPMvEPEdwhUWLUkwa+twmTpmpYLg7eLs/odbU?= =?us-ascii?Q?Ad9wyNyKevovtaVyZiXaB3Rtetg1IRibh7hY6Jw025kzhx5rXl3OfbeflPEl?= =?us-ascii?Q?JYUmQ6WpjZvCK9SbPDQx9yG4FmzESmvZEEEH9RWeC9N3NQC6n+eUm8/hLf2G?= =?us-ascii?Q?YbHQvN5JYuc4dWgKpx/p4h5VHjIcThpwJvkE/mAu7g5x8Kvbw8ikV/BAu5dY?= =?us-ascii?Q?eh2RjQQJ2EHF98bEKgzAqjq7QjBnht/oLchYECPQc3IAWCsgz52H6TiHaj38?= =?us-ascii?Q?lSUR/WvWNRdkdlrDfcSGO2Gy5f1v2JBGgUleJmGfDatkg3uUtDQfbda59t7K?= =?us-ascii?Q?XI+bjDkwP5+WDiUZVUN8H9jB9/ehpz3n4TZ+/wBkHua4xrHARhsVyrFM+LAS?= =?us-ascii?Q?s2Pwv25BLfv8XIe/nYYusbkVDUNnjIzWuTz8iKR9JAJ/MKZkJymlm1poQPdc?= =?us-ascii?Q?E8GmSe5LzffBMPkT5aINZOvVkdxpy5mhSqipHeaOjlNX9/8tiKfnYkiyt5fb?= =?us-ascii?Q?0Q4yDYy5+hOAkKcDlPUlPoFHYtdYwYzaIhqhNidpbutzEykHMBZ/AWSsqXit?= =?us-ascii?Q?7Qny3D8fQPhwX1j94EpztsFS79mHT2AXKRXrnOUB1asAg5HgqAaNqjIhMQST?= =?us-ascii?Q?qCT6daJZEISubWg2Vcb9/TFC9bXfnoiFDcTGOrNX7qfdrKRE3W3Fr2hR+FAk?= =?us-ascii?Q?W3ZKLEqIpXFXKL1WxAsy+jpOpcFcctqyQFkJ9P1aB1oYOnQ2hNfm7f0bQMKk?= =?us-ascii?Q?ryITZ5Q5HNZb2uxFKoW80as97WlAvuHYefK52U3H5NtjQG5v034NgxSuOKxt?= =?us-ascii?Q?WINYkFvIW9uxov1k5BRO1q27cKeeHasHmyFL4NGMMGe0O4Di8C6boYMIM8B5?= =?us-ascii?Q?rN4iL0gtd7QfmHTsUJlu86dA7ccHwIR0MvaUf7OYbBP9U+0hF4ErrzRsFiIj?= =?us-ascii?Q?wvMzzWczhIHiG9Gt5TlgfsF0HMTSpyLaxbNjCk6fAjPPr75dD9TbV0QoZKyx?= =?us-ascii?Q?hdoNB8c2WfqzkFSm4HI3oG7Mn7kPDAOdkdlvxS5wLPAp39maS4s641LUCCRk?= =?us-ascii?Q?Q3ZPanZnU5S8OJOsmLvPGo6RkGaDqRVmaUZAngWeNisGKzGXFfw5R67q9aGH?= =?us-ascii?Q?Q5KugoRPcgISmfVzHMm4SOvgyUwh/uRJIk9+2ZOUaFOqIf4Hqgfg1N9QylnG?= =?us-ascii?Q?ugb/mCr/pFr+UVouCOGMciKEv1AW7pW2kzA2W+jKNLTN88afaypf7OotW0wn?= =?us-ascii?Q?j0Sf6tWqcl6sMRzS6zQP2qGFU0iZRZwZCYx70IR16ujvjMRKh2j9FI4jXkbl?= =?us-ascii?Q?3UIT+nLdbk2BKkU7nLNK/eG6+0gtmemjPSt4vSNUZ6LyJUKF?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 263c8188-3184-42fa-af18-08dee2ac6aef X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jul 2026 20:05:29.0821 (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: TXWKSXW9Mg0S6B+a2IUHAbUI0mQ4IMPe4OuEbXItYXXAXw1GFo0prw3S0wsM2OYV X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8875 On Tue, Jul 14, 2026 at 11:48:51AM -0700, Nicolin Chen wrote: > arm_vsmmu_cache_invalidate() allocated a buffer for the entire user request > array, walked the array converting each of the commands, and issued those > converted commands to the cmdq in CMDQ_BATCH_ENTRIES sized chunks, carrying > the sub-array bookkeeping all on its own. > > The iommufd core now iterates the invalidation array and re-invokes the op > with the not-yet-handled sub-array, so the driver only has to proceed with > a single chunk per call. > > Instead of a per-array allocation, use a fixed on-stack batch to copy from > the userspace array. If the copy fails due to nonzero padding (VMM violates > the ABI), fail the entire batch. > > Convert the whole batch before issuing any of it: a malformed command is a > userspace bug, so the first illegal command fails the batch as a unit, > issuing nothing and leaving array->entry_num at zero, the same way the copy > above bails on nonzero padding. A batch that converts cleanly is issued in > full, so the op returns either a handled count with no error or zero with > an error. > > A zero-length array now returns success once the data type gets validated, > matching the documented probe behavior, rather than the -EINVAL that the > full-array copy helper would previously return. > > This also fixes two long-standing bugs: > 1) On a conversion failure the old code reported commands that it had > converted but not yet issued, so user space advanced its consumer > index past invalidations that never reached the cmdq. > 2) A zero-length array was rejected with -EINVAL, although the uAPI > documents it as a valid request that only probes the data type. > > Reviewed-by: Kevin Tian > Reviewed-by: Pranjal Shrivastava > Assisted-by: Claude:claude-opus-4-8 > Signed-off-by: Nicolin Chen > --- > .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c | 68 +++++++++++-------- > 1 file changed, 38 insertions(+), 30 deletions(-) Reviewed-by: Jason Gunthorpe Jason