Commit b4ff830e authored by Jason Gunthorpe's avatar Jason Gunthorpe
Browse files

iommufd: Do not add the same hwpt to the ioas->hwpt_list twice 

The hwpt is added to the hwpt_list only during its creation, it is never
added again. This hunk is some missed leftover from rework. Adding it
twice will corrupt the linked list in some cases.

It effects HWPT specific attachment, which is something the test suite
cannot cover until we can create a legitimate struct device with a
non-system iommu "driver" (ie we need the bus removed from the iommu code)

Cc: stable@vger.kernel.org
Fixes: e8d57210 ("iommufd: Add kAPI toward external drivers for physical devices")
Link: https://lore.kernel.org/r/1-v1-4336b5cb2fe4+1d7-iommufd_hwpt_jgg@nvidia.com


Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reported-by: default avatarKevin Tian <kevin.tian@intel.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent b3551ead

drivers/iommu/iommufd/device.c

+0 −4
Original line number Diff line number Diff line
@@ -344,10 +344,6 @@ int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) 
		rc = iommufd_device_do_attach(idev, hwpt);

		if (rc)

			goto out_put_pt_obj;



		mutex_lock(&hwpt->ioas->mutex);

		list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list);

		mutex_unlock(&hwpt->ioas->mutex);

		break;

	}

	case IOMMUFD_OBJ_IOAS: {