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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?EifxrTcs9o7vg9cRvbMaPTM4Pjv8d9fPy/vRboS3i6+OhYn5m+l9HaRT47zF?= =?us-ascii?Q?5FsU/uj+bpJJc670RFEidMywlBfcsDym3vN+beSEupxDmGr/uyLNjAd/NBwP?= =?us-ascii?Q?dwmm5YNnpxUACF637tElAzH1EQSjW/kS0fZXrzXXwWkC3vAbwITV9dcqj2Pd?= =?us-ascii?Q?GjiusrDh5EXwzIM7GgR+ItjJA8h2AQK4eaVX/qgHICtFFjcYmMUmNjBBcGS1?= =?us-ascii?Q?8CycX4fK573PD4bRaJl3asw+Z68bB8ut+Hltc/FcLuUgI/+6E1kghI27D45i?= =?us-ascii?Q?WhMmc8C8Pau4mHG/NspBe6xqcD4AjV8jlhdIkE6rcJ3dYg06S9TCq0wlVZHF?= =?us-ascii?Q?Of4d4wxapum5wBnG2NQHS3MBgklPSS9i03o9Wi8uUpav5sljtKYk43M8+OCN?= =?us-ascii?Q?dscaY9bTOzU6fsvaKN7/Z2Kd/U4xAG46AyYI5saXxr+alI2u8MNeMThXAtSL?= =?us-ascii?Q?cpB1T3lD6rsEhuUI66Evg4OP42BQcPz/xHcOerrSX7vDNGaUsEhA65HUiXsG?= =?us-ascii?Q?dmYe8WEBdMaylkdRWaCjzxX7q91TDgr6dGjn83ZI9rTyHffOXAv4TvyYUbxR?= =?us-ascii?Q?0rKofjy4f4O31/bOC1Q7Y4HpDcak00KO1QrPXQQATuzlj0HAnhX9zIBwrhwL?= =?us-ascii?Q?tK79FGlzW/BfrvtRvL7i5WO+nW1O+LW9rISjGanwCXlmIrb20PNx/tRbTeuY?= =?us-ascii?Q?TWh5DHR43epOmJY2WIrsvmeuLrGBeQVBt/Tx8Q48jVwsjUHB7i+8RIB+wmXS?= =?us-ascii?Q?cIUeLvL2LMcHo+XaVf2N6VUPWU47vU5W2nBewLeSEo6JlkXD3IHSq2T3Bc5j?= =?us-ascii?Q?ZheTOpkjY9g2YAYJxIcZ8lqOh8/lwSXFq7u5+xh+5M1pRpemrcHhgLRzqLNe?= =?us-ascii?Q?2u6JHUaKwbQQy/zPCpXeP8NbkT3TgD8/540EMstAHA3QSqLco1G6W8bbN9+O?= =?us-ascii?Q?KAQUK6JCnNADTRvWWDvZxorDfoRQuScD6Y6l8hDGkWtXmyqmtPT5IztC/0+B?= =?us-ascii?Q?5HUX/UOsl9r3iqELi/hrAmiRWlJYORzhuPecCvVZgSc4vkqiTYEyB5hRxP6q?= =?us-ascii?Q?XpoDlGVOM1bY6PTMA2F/SeonSeS1BiV+R02W1IqaroENxSUcB82p331PQCE+?= =?us-ascii?Q?8h1lAMqoAhbSmCjV8PudJ3dFFVS48yfDj9GIpzcSvtiXujvZ3Jr3CzcGVQLH?= =?us-ascii?Q?FtFFbGPkJ4AgmEfBlVFUlJ8P+HrdI7AkWt0S1C23odU3RCe7BVCrG71rg8vo?= =?us-ascii?Q?asaI2n5M0yn2+POy3TOPIYjt83XDEsVcZJignb7Tv30vlLJlBdpW1g5M4idV?= =?us-ascii?Q?0kvQCAIa/44fmm7TSNkrb3P1LjpjSxSVvZTZqEVsly/9fFJuP2JzGgQWbHYA?= =?us-ascii?Q?Wn+SrpqB3q80a7xFXaCiK1dw49Qp70ec5VFLrp13HoHq/d4V5sSbRjrsu+p8?= =?us-ascii?Q?+XS3rK8tqfS/+/bvOA8CNofRYPgC9k5bRQN+6oi+Z9UEl6ZDXL72RkAVNmMA?= =?us-ascii?Q?MUeV+iN6eexMSQTq7EMdY8UMVgzQmvStW/jwPRzkg9jSfS5SQ2+LUt4k+/Zj?= =?us-ascii?Q?Q36rnOdvxcA+2kwavb4aLjdSpfVwoATuWLGhVws00jktpAZWYFNpWuuAmH5L?= =?us-ascii?Q?fzFS9Jel6boJQz9T33VcKr88RO0/dr2RUGWWql3jFck0K1PeGwVndCFVqneq?= =?us-ascii?Q?Pmm+jwUk046EZ5uNa2QcQt669TBCSiVK2PW0e6qUMba3UKq0?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 269dc1f0-f06a-41c2-7696-08de965a68cd X-MS-Exchange-CrossTenant-AuthSource: CY1PR12MB9601.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Apr 2026 17:06:58.4697 (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: NRX4yOobVUqt7QGT46AKbruszeYVmueavPc4zPrhnkXHYwXZZac38f4AaR0hkoKd X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7940 On Thu, Apr 02, 2026 at 10:11:39PM -0700, Jacob Pan wrote: > From: Jason Gunthorpe > > Allow iommufd to bind devices without an IOMMU (noiommu mode) by creating > a dummy IOMMU group for such devices and skipping hwpt operations. > > This enables noiommu devices to operate through the same iommufd API as IOMMU- > capable devices. > > Signed-off-by: Jason Gunthorpe > Signed-off-by: Jacob Pan > > --- > v3: > - handle new error cases iommufd_device_bind. (Mostafa) > --- > drivers/iommu/iommufd/device.c | 126 +++++++++++++++++++++++---------- > 1 file changed, 87 insertions(+), 39 deletions(-) > @@ -294,11 +334,10 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, > *id = idev->obj.id; > return idev; > > -out_release_owner: > - iommu_device_release_dma_owner(dev); > -out_group_put: > - iommufd_put_group(igroup); > +err_out: > + iommufd_object_abort_and_destroy(ictx, &idev->obj); > return ERR_PTR(rc); I fed this to Sashiko and it pointed out the abort flow here will call iommufd_device_destroy() bit it isn't prepared to handle a partially initialized idev. It looks like igroup is only set once it is sufficiently initialized so: @@ -211,6 +211,8 @@ void iommufd_device_destroy(struct iommufd_object *obj) struct iommufd_device *idev = container_of(obj, struct iommufd_device, obj); + if (!idev->igroup) + return; if (!is_vfio_noiommu(idev)) iommu_device_release_dma_owner(idev->dev); iommufd_put_group(idev->igroup); Should fix it, but lets add a comment because it is pretty fragile: @@ -335,6 +337,10 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, return idev; err_out: + /* + * Be careful that iommufd_device_destroy() can handle partial + * initialization. + */ iommufd_object_abort_and_destroy(ictx, &idev->obj); return ERR_PTR(rc); Jason